title: Logarithm

text: This series can be derived from the above Taylor series. It converges quicker than the Taylor series, especially if is close to 1. For example, for , the first three terms of the second series approximate with an error of about . The quick convergence for close to 1 can be taken advantage of in the following way: given a low-accuracy approximation and putting


title: Logarithm

text: The better the initial approximation is, the closer is to 1, so its logarithm can be calculated efficiently. can be calculated using the exponential series, which converges quickly provided is not too large. Calculating the logarithm of larger can be reduced to smaller values of by writing , so that .


title: Logarithm

text: A closely related method can be used to compute the logarithm of integers. Putting formula_66 in the above series, it follows that:


title: Logarithm

text: If the logarithm of a large integer  is known, then this series yields a fast converging series for , with a rate of convergence of formula_68.


title: Logarithm

text: The arithmetic–geometric mean yields high precision approximations of the natural logarithm. Sasaki and Kanada showed in 1982 that it was particularly fast for precisions between 400 and 1000 decimal places, while Taylor series methods were typically faster when less precision was needed. In their work is approximated to a precision of (or  precise bits) by the following formula (due to Carl Friedrich Gauss):


title: Logarithm

text: Here denotes the arithmetic–geometric mean of and . It is obtained by repeatedly calculating the average (arithmetic mean) and formula_70 (geometric mean) of and then let those two numbers become the next and . The two numbers quickly converge to a common limit which is the value of . is chosen such that


title: Logarithm

text: to ensure the required precision. A larger makes the calculation take more steps (the initial and are farther apart so it takes more steps to converge) but gives more precision. The constants and can be calculated with quickly converging series.


title: Logarithm

text: While at Los Alamos National Laboratory working on the Manhattan Project, Richard Feynman developed a bit-processing algorithm, to compute the logarithm, that is similar to long division and was later used in the Connection Machine. The algorithm uses the fact that every real number is representable as a product of distinct factors of the form . The algorithm sequentially builds that product , starting with and : if , then it changes to . It then increases formula_72 by one regardless. The algorithm stops when is large enough to give the desired accuracy. Because is the sum of the terms of the form corresponding to those for which the factor was included in the product , may be computed by simple addition, using a table of for all . Any base may be used for the logarithm table.


title: Logarithm

text: Logarithms have many applications inside and outside mathematics. Some of these occurrences are related to the notion of scale invariance. For example, each chamber of the shell of a nautilus is an approximate copy of the next one, scaled by a constant factor. This gives rise to a logarithmic spiral. Benford's law on the distribution of leading digits can also be explained by scale invariance. Logarithms are also linked to self-similarity. For example, logarithms appear in the analysis of algorithms that solve a problem by dividing it into two similar smaller problems and patching their solutions. The dimensions of self-similar geometric shapes, that is, shapes whose parts resemble the overall picture are also based on logarithms. Logarithmic scales are useful for quantifying the relative change of a value as opposed to its absolute difference. Moreover, because the logarithmic function grows very slowly for large , logarithmic scales are used to compress large-scale scientific data. Logarithms also occur in numerous scientific formulas, such as the Tsiolkovsky rocket equation, the Fenske equation, or the Nernst equation.


title: Logarithm

text: Scientific quantities are often expressed as logarithms of other quantities, using a "logarithmic scale". For example, the decibel is a unit of measurement associated with logarithmic-scale quantities. It is based on the common logarithm of ratios—10 times the common logarithm of a power ratio or 20 times the common logarithm of a voltage ratio. It is used to quantify the loss of voltage levels in transmitting electrical signals, to describe power levels of sounds in acoustics, and the absorbance of light in the fields of spectrometry and optics. The signal-to-noise ratio describing the amount of unwanted noise in relation to a (meaningful) signal is also measured in decibels. In a similar vein, the peak signal-to-noise ratio is commonly used to assess the quality of sound and image compression methods using the logarithm.


title: Logarithm

text: The strength of an earthquake is measured by taking the common logarithm of the energy emitted at the quake. This is used in the moment magnitude scale or the Richter magnitude scale. For example, a 5.0 earthquake releases 32 times and a 6.0 releases 1000 times the energy of a 4.0. Apparent magnitude measures the brightness of stars logarithmically. In chemistry the negative of the decimal logarithm, the decimal , is indicated by the letter p. For instance, pH is the decimal cologarithm of the activity of hydronium ions (the form hydrogen ions take in water). The activity of hydronium ions in neutral water is 10 mol·L, hence a pH of 7. Vinegar typically has a pH of about 3. The difference of 4 corresponds to a ratio of 10 of the activity, that is, vinegar's hydronium ion activity is about .


title: Logarithm

text: Semilog (log–linear) graphs use the logarithmic scale concept for visualization: one axis, typically the vertical one, is scaled logarithmically. For example, the chart at the right compresses the steep increase from 1 million to 1 trillion to the same space (on the vertical axis) as the increase from 1 to 1 million. In such graphs, exponential functions of the form appear as straight lines with slope equal to the logarithm of . Log-log graphs scale both axes logarithmically, which causes functions of the form to be depicted as straight lines with slope equal to the exponent . This is applied in visualizing and analyzing power laws.


title: Logarithm

text: Logarithms occur in several laws describing human perception: Hick's law proposes a logarithmic relation between the time individuals take to choose an alternative and the number of choices they have. Fitts's law predicts that the time required to rapidly move to a target area is a logarithmic function of the distance to and the size of the target. In psychophysics, the Weber–Fechner law proposes a logarithmic relationship between stimulus and sensation such as the actual vs. the perceived weight of an item a person is carrying. (This "law", however, is less realistic than more recent models, such as Stevens's power law.)


title: Logarithm

text: Psychological studies found that individuals with little mathematics education tend to estimate quantities logarithmically, that is, they position a number on an unmarked line according to its logarithm, so that 10 is positioned as close to 100 as 100 is to 1000. Increasing education shifts this to a linear estimate (positioning 1000 10 times as far away) in some circumstances, while logarithms are used when the numbers to be plotted are difficult to plot linearly.


title: Logarithm

text: Logarithms arise in probability theory: the law of large numbers dictates that, for a fair coin, as the number of coin-tosses increases to infinity, the observed proportion of heads approaches one-half. The fluctuations of this proportion about one-half are described by the law of the iterated logarithm.


title: Logarithm

text: Logarithms also occur in log-normal distributions. When the logarithm of a random variable has a normal distribution, the variable is said to have a log-normal distribution. Log-normal distributions are encountered in many fields, wherever a variable is formed as the product of many independent positive random variables, for example in the study of turbulence.


title: Logarithm

text: Logarithms are used for maximum-likelihood estimation of parametric statistical models. For such a model, the likelihood function depends on at least one parameter that must be estimated. A maximum of the likelihood function occurs at the same parameter-value as a maximum of the logarithm of the likelihood (the ""log likelihood""), because the logarithm is an increasing function. The log-likelihood is easier to maximize, especially for the multiplied likelihoods for independent random variables.


title: Logarithm

text: Benford's law describes the occurrence of digits in many data sets, such as heights of buildings. According to Benford's law, the probability that the first decimal-digit of an item in the data sample is (from 1 to 9) equals , "regardless" of the unit of measurement. Thus, about 30% of the data can be expected to have 1 as first digit, 18% start with 2, etc. Auditors examine deviations from Benford's law to detect fraudulent accounting.


title: Logarithm

text: The logarithm transformation is a type of data transformation used to bring the empirical distribution closer to the assumed one.


title: Logarithm

text: Analysis of algorithms is a branch of computer science that studies the performance of algorithms (computer programs solving a certain problem). Logarithms are valuable for describing algorithms that divide a problem into smaller ones, and join the solutions of the subproblems.


title: Logarithm

text: For example, to find a number in a sorted list, the binary search algorithm checks the middle entry and proceeds with the half before or after the middle entry if the number is still not found. This algorithm requires, on average, comparisons, where is the list's length. Similarly, the merge sort algorithm sorts an unsorted list by dividing the list into halves and sorting these first before merging the results. Merge sort algorithms typically require a time approximately proportional to . The base of the logarithm is not specified here, because the result only changes by a constant factor when another base is used. A constant factor is usually disregarded in the analysis of algorithms under the standard uniform cost model.


title: Logarithm

text: A function  is said to grow logarithmically if is (exactly or approximately) proportional to the logarithm of . (Biological descriptions of organism growth, however, use this term for an exponential function.) For example, any natural number  can be represented in binary form in no more than  bits. In other words, the amount of memory needed to store grows logarithmically with .


title: Logarithm

text: Entropy is broadly a measure of the disorder of some system. In statistical thermodynamics, the entropy "S" of some physical system is defined as


title: Logarithm

text: The sum is over all possible states  of the system in question, such as the positions of gas particles in a container. Moreover, is the probability that the state  is attained and is the Boltzmann constant. Similarly, entropy in information theory measures the quantity of information. If a message recipient may expect any one of possible messages with equal likelihood, then the amount of information conveyed by any one such message is quantified as bits.


title: Logarithm

text: Lyapunov exponents use logarithms to gauge the degree of chaoticity of a dynamical system. For example, for a particle moving on an oval billiard table, even small changes of the initial conditions result in very different paths of the particle. Such systems are chaotic in a deterministic way, because small measurement errors of the initial state predictably lead to largely different final states. At least one Lyapunov exponent of a deterministically chaotic system is positive.


title: Logarithm

text: Logarithms occur in definitions of the dimension of fractals. Fractals are geometric objects that are self-similar in the sense that small parts reproduce, at least roughly, the entire global structure. The Sierpinski triangle (pictured) can be covered by three copies of itself, each having sides half the original length. This makes the Hausdorff dimension of this structure . Another logarithm-based notion of dimension is obtained by counting the number of boxes needed to cover the fractal in question.


title: Logarithm

text: Logarithms are related to musical tones and intervals. In equal temperament, the frequency ratio depends only on the interval between two tones, not on the specific frequency, or pitch, of the individual tones. For example, the note "A" has a frequency of 440 Hz and "B-flat" has a frequency of 466 Hz. The interval between "A" and "B-flat" is a semitone, as is the one between "B-flat" and "B" (frequency 493 Hz). Accordingly, the frequency ratios agree:


title: Logarithm

text: Therefore, logarithms can be used to describe the intervals: an interval is measured in semitones by taking the logarithm of the frequency ratio, while the logarithm of the frequency ratio expresses the interval in cents, hundredths of a semitone. The latter is used for finer encoding, as it is needed for non-equal temperaments.


title: Logarithm

text: Natural logarithms are closely linked to counting prime numbers (2, 3, 5, 7, 11, ...), an important topic in number theory. For any integer , the quantity of prime numbers less than or equal to is denoted . The prime number theorem asserts that is approximately given by


title: Logarithm

text: in the sense that the ratio of and that fraction approaches 1 when tends to infinity. As a consequence, the probability that a randomly chosen number between 1 and is prime is inversely proportional to the number of decimal digits of . A far better estimate of is given by the offset logarithmic integral function , defined by


title: Logarithm

text: The Riemann hypothesis, one of the oldest open mathematical conjectures, can be stated in terms of comparing and . The Erdős–Kac theorem describing the number of distinct prime factors also involves the natural logarithm.


title: Logarithm

text: are called "complex logarithms" of , when is (considered as) a complex number. A complex number is commonly represented as , where and are real numbers and is an imaginary unit, the square of which is −1. Such a number can be visualized by a point in the complex plane, as shown at the right. The polar form encodes a non-zero complex number  by its absolute value, that is, the (positive, real) distance  to the origin, and an angle between the real () axis" " and the line passing through both the origin and . This angle is called the argument of .


title: Logarithm

text: Using the geometrical interpretation of sine and cosine and their periodicity in , any complex number  may be denoted as


title: Logarithm

text: for any integer number . Evidently the argument of is not uniquely specified: both and are valid arguments of for all integers , because adding  radians or "k"⋅360° to corresponds to "winding" around the origin counter-clock-wise by  turns. The resulting complex number is always , as illustrated at the right for . One may select exactly one of the possible arguments of as the so-called "principal argument", denoted , with a capital , by requiring to belong to one, conveniently selected turn, e.g. or . These regions, where the argument of is uniquely determined are called "branches" of the argument function.


title: Logarithm

text: where is the unique real natural logarithm, denote the complex logarithms of , and is an arbitrary integer. Therefore, the complex logarithms of , which are all those complex values for which the  power of equals , are the infinitely many values


title: Logarithm

text: Taking such that is within the defined interval for the principal arguments, then is called the "principal value" of the logarithm, denoted , again with a capital . The principal argument of any positive real number  is 0; hence is a real number and equals the real (natural) logarithm. However, the above formulas for logarithms of products and powers do "not" generalize to the principal value of the complex logarithm.


title: Logarithm

text: The illustration at the right depicts , confining the arguments of to the interval . This way the corresponding branch of the complex logarithm has discontinuities all along the negative real  axis, which can be seen in the jump in the hue there. This discontinuity arises from jumping to the other boundary in the same branch, when crossing a boundary, i.e. not changing to the corresponding -value of the continuously neighboring branch. Such a locus is called a branch cut. Dropping the range restrictions on the argument makes the relations "argument of ", and consequently the "logarithm of ", multi-valued functions.


title: Logarithm

text: Exponentiation occurs in many areas of mathematics and its inverse function is often referred to as the logarithm. For example, the logarithm of a matrix is the (multi-valued) inverse function of the matrix exponential. Another example is the "p"-adic logarithm, the inverse function of the "p"-adic exponential. Both are defined via Taylor series analogous to the real case. In the context of differential geometry, the exponential map maps the tangent space at a point of a manifold to a neighborhood of that point. Its inverse is also called the logarithmic (or log) map.


title: Logarithm

text: In the context of finite groups exponentiation is given by repeatedly multiplying one group element  with itself. The discrete logarithm is the integer "" solving the equation


title: Logarithm

text: where is an element of the group. Carrying out the exponentiation can be done efficiently, but the discrete logarithm is believed to be very hard to calculate in some groups. This asymmetry has important applications in public key cryptography, such as for example in the Diffie–Hellman key exchange, a routine that allows secure exchanges of cryptographic keys over unsecured information channels. Zech's logarithm is related to the discrete logarithm in the multiplicative group of non-zero elements of a finite field.


title: Logarithm

text: Further logarithm-like inverse functions include the "double logarithm" , the "super- or hyper-4-logarithm" (a slight variation of which is called iterated logarithm in computer science), the Lambert W function, and the logit. They are the inverse functions of the double exponential function, tetration, of , and of the logistic function, respectively.


title: Logarithm

text: From the perspective of group theory, the identity expresses a group isomorphism between positive reals under multiplication and reals under addition. Logarithmic functions are the only continuous isomorphisms between these groups. By means of that isomorphism, the Haar measure (Lebesgue measure)  on the reals corresponds to the Haar measure  on the positive reals. The non-negative reals not only have a multiplication, but also have addition, and form a semiring, called the probability semiring; this is in fact a semifield. The logarithm then takes multiplication to addition (log multiplication), and takes addition to log addition (LogSumExp), giving an isomorphism of semirings between the probability semiring and the log semiring.


title: Logarithm

text: Logarithmic one-forms  appear in complex analysis and algebraic geometry as differential forms with logarithmic poles.


title: Ben Affleck filmography

text: Ben Affleck is an American actor and filmmaker. He made his film debut with a minor part for "The Dark End of the Street" (1981). He went on to appear in several television shows, including the PBS educational programs "The Voyage of the Mimi" (1984) and "The Second Voyage of the Mimi" (1988), and an episode of the "ABC Afterschool Special" in 1986. Affleck played an antisemite in the sports film "School Ties" (1992) and featured as a regular on the television drama "Against the Grain" (1993). He gained attention for playing the supporting part of a high-school senior in Richard Linklater's cult film "Dazed and Confused" (1993), after which he had his first leading role in Rich Wilkes's comedy "Glory Daze" (1995).


title: Ben Affleck filmography

text: In 1997, Affleck played a comics artist in Smith's art-house success "Chasing Amy". He wrote the script and starred with Matt Damon in Gus Van Sant's drama film "Good Will Hunting" . Affleck and Damon won the Academy Award for Best Original Screenplay. He next starred with Bruce Willis in Michael Bay's $554 million-grossing science fiction film "Armageddon" (1998), which proved to be his biggest commercial success to that point. In 2000, Affleck formed a production company with Damon and Sean Bailey, named LivePlanet, which produced "Project Greenlight" (2001–05, 2015), a television series that provides training to first-time filmmakers. He has served as the executive producer of several projects directed by the winners of the show. Affleck played opposite Kate Beckinsale in Bay's war film "Pearl Harbor" (2001), which despite negative reviews was a box office hit. His career subsequently went through a period of decline when he starred in a series of critical and commercial failures, including the superhero film "Daredevil" (2003), and the comedies "Gigli" (2003) and "Surviving Christmas" (2004). He later made a comeback with the biopic "Hollywoodland" (2006), in which his portrayal of George Reeves earned him a Golden Globe nomination.


title: Ben Affleck filmography

text: In 2007, Affleck made his feature film directorial debut with "Gone Baby Gone", a thriller based on the novel by Dennis Lehane, which was critically praised. He went on to act in and direct two acclaimed features for Warner Bros.the crime drama "The Town" (2010) and the thriller "Argo" (2012). The latter, about the 1979 Iran hostage crisis in which he played the intelligence agent Tony Mendez, won the Academy Award for Best Picture and Affleck won the Golden Globe and BAFTA for Best Director. In 2014, Affleck played a man accused of murdering his wife in David Fincher's thriller "Gone Girl". Two years later, he starred as Batman in the superhero film "" (2016) which grossed a worldwide total of over $873 million at the box office—his highest-grossing release, a role he reprised in subsequent installments set in the DC Extended Universe.


title: Bailee Madison

text: Bailee Madison Riley (born October 15, 1999) is an American actress and singer. She first gained acclaim for her role as May Belle Aarons in the fantasy drama film "Bridge to Terabithia" (2007). Madison received further recognition for her starring roles as Isabelle in the war drama film "Brothers" (2009), Sally Hurst in the horror film "Don't Be Afraid of the Dark" (2010), Maggie in the romantic comedy film "Just Go with It" (2011), Harper Simmons in the comedy film "Parental Guidance" (2012), Ida Clayton in the family film "Cowgirls 'n Angels" (2012), Clementine in the fantasy film "Northpole" (2014), Kinsey in the slasher film "" (2018), and Avery in the Netflix film "A Week Away" (2021).


title: Bailee Madison

text: On television, she appeared as Maxine Russo in the fantasy sitcom "Wizards of Waverly Place" (2011), young Snow White in the fantasy drama series "Once Upon a Time" (2012–2016), Hillary Harrison in the sitcom "Trophy Wife" (2013–2014), and Sophia Quinn in the drama series "The Fosters" (2014–2016). From 2015 to 2021, Madison starred as Grace Russell in the Hallmark Channel comedy-drama series "Good Witch". In 2022, she began her role as Imogen Adams in the horror thriller series "", a spinoff of "Pretty Little Liars".


title: Bailee Madison

text: Madison was born in Fort Lauderdale, Florida, the youngest of seven children. She has four brothers and two sisters. Her older sister, Kaitlin Vilasuso, is also an actress. Her mother is Patricia Riley. She began her career when she was two weeks old, appearing in an Office Depot commercial. Since then, she has appeared in several national commercials for major companies including Disney, SeaWorld, and Cadillac. She also serves as a national youth spokesperson for the childhood-cancer charity Alex's Lemonade Stand Foundation.


title: Bailee Madison

text: In 2010, Madison starred in her first leading role in the supernatural horror film "Don't Be Afraid of the Dark". She starred alongside Katie Holmes and Guy Pearce, portraying the role of Sally Hurst, a lonely withdrawn child who is sent to live with her father and his new girlfriend. Roger Ebert of the "Chicago Sun-Times" gave the film 3½ stars out of 4, calling it "a very good haunted house film" and adding that it "milks our frustration deliciously."


title: Bailee Madison

text: In 2013, Madison began playing Hillary on the TV sitcom "Trophy Wife", replacing Gianna LePera who played the character in the pilot. In 2014, she began playing the recurring role of Sophia Quinn in the ABC Family drama "The Fosters". In 2015, she began playing Grace Russell, the daughter of Cassie Nightingale, in the Hallmark series "Good Witch". Madison continued in the role until the end of the fifth season in 2019.


title: Bailee Madison

text: In 2017, it was announced that Madison would star in an adaptation of Rachel Bateman's novel "Someone Else's Summer".


title: Bailee Madison

text: In 2018, Madison portrayed the role of Kinsey, a rebellious child in the slasher film "." She starred alongside Christina Hendricks and Martin Henderson, as her parents. Although the film received a mixed response from critics, Madison's performance was praised and was relatively successful at the box office.


title: Bailee Madison

text: In 2021, Madison played the female lead in a teen Christian musical drama, "A Week Away", alongside Kevin Quinn. Netflix released the film on March 26. The following year, she played Imogen Adams in the HBO Max horror-thriller series "", a spin-off of "Pretty Little Liars", to critical acclaim.


title: Bailee Madison

text: Madison has served as the national youth spokesperson for Alex's Lemonade Stand Foundation since 2010, an organization that encourages kids to fundraise and spread awareness of pediatric cancer by running their own lemonade stands. In January 2018, Madison's first novel was published, "Losing Brave", a Young-Adult Mystery which was co-written with Stefne Miller. Since November 2018, she has co-hosted the podcast "Just Between Us" with her sister Kaitlin Vilasuso.


title: Dementia with Lewy bodies

text: Dementia with Lewy bodies (DLB) is a type of dementia characterized by changes in sleep, behavior, cognition, movement, and regulation of automatic bodily functions. Memory loss is not always an early symptom. The disease worsens over time and is usually diagnosed when cognitive impairment interferes with normal daily functioning. Together with Parkinson's disease dementia, DLB is one of the two Lewy body dementias. It is a common form of dementia, but the prevalence is not known accurately and many diagnoses are missed. The disease was first described by Kenji Kosaka in 1976.


title: Dementia with Lewy bodies

text: REM sleep behavior disorder (RBD)—in which people lose the muscle paralysis (atonia) that normally occurs during REM sleep and act out their dreams—is a core feature. RBD may appear years or decades before other symptoms. Other core features are visual hallucinations, marked fluctuations in attention or alertness, and parkinsonism (slowness of movement, trouble walking, or rigidity). A presumptive diagnosis can be made if several disease features or biomarkers are present; the diagnostic workup may include blood tests, neuropsychological tests, imaging, and sleep studies. A definitive diagnosis usually requires an autopsy.


title: Dementia with Lewy bodies

text: Most people with DLB do not have affected family members, although occasionally DLB runs in a family. The exact cause is unknown but involves formation of abnormal clumps of protein in neurons throughout the brain. Manifesting as Lewy bodies (discovered in 1912 by Frederic Lewy) and Lewy neurites, these clumps affect both the central and the autonomic nervous systems. Heart function and every level of gastrointestinal function—from chewing to defecation—can be affected, constipation being one of the most common symptoms. Low blood pressure upon standing can also occur. DLB commonly causes psychiatric symptoms, such as altered behavior, depression, or apathy.


title: Dementia with Lewy bodies

text: DLB typically begins after the age of fifty, and people with the disease have an average life expectancy, with wide variability, of about four years after diagnosis. There is no cure or medication to stop the disease from progressing, and people in the latter stages of DLB may be unable to care for themselves. Treatments aim to relieve some of the symptoms and reduce the burden on caregivers. Medicines such as donepezil and rivastigmine can temporarily improve cognition and overall functioning, and melatonin can be used for sleep-related symptoms. Antipsychotics are usually avoided, even for hallucinations, because severe reactions occur in almost half of people with DLB, and their use can result in death. Management of the many different symptoms is challenging, as it involves multiple specialties and education of caregivers.


title: Dementia with Lewy bodies

text: Dementia with Lewy bodies (DLB) is a type of dementia, a group of diseases involving progressive neurodegeneration of the central nervous system. It is one of the two Lewy body dementias, along with Parkinson's disease dementia.


title: Dementia with Lewy bodies

text: Dementia with Lewy bodies can be classified in other ways. The atypical parkinsonian syndromes include DLB, along with other conditions. Also, DLB is a synucleinopathy, meaning that it is characterized by abnormal deposits of alpha-synuclein protein in the brain. The synucleinopathies include Parkinson's disease, multiple system atrophy, and other rarer conditions.


title: Dementia with Lewy bodies

text: The vocabulary of diseases associated with Lewy pathology causes confusion. "Lewy body dementia" (the umbrella term that encompasses the clinical diagnoses of dementia with Lewy bodies and Parkinson's disease dementia) differs from "Lewy body disease" (the term used to describe pathological findings of Lewy bodies on autopsy). Because individuals with Alzheimer's are often found on autopsy to also have Lewy bodies, DLB has been characterized as an Alzheimer disease-related dementia; the term "Lewy body variant of Alzheimer disease" is no longer used because the predominant pathology for these individuals is related to Alzheimer's. Even the term "Lewy body disease" may not describe the true nature of this group of diseases; a unique genetic architecture may predispose individuals to specific "diseases with Lewy bodies", and naming controversies continue in 2022.


title: Dementia with Lewy bodies

text: DLB is dementia that occurs with "some combination of fluctuating cognition, recurrent visual hallucinations, rapid eye movement (REM) sleep behavior disorder (RBD), and parkinsonism", according to Armstrong (2019), when Parkinson's disease is "not" well established before the dementia occurs. DLB has widely varying symptoms and is more complex than many other dementias. Several areas of the nervous system (such as the autonomic nervous system and numerous regions of the brain) can be affected by Lewy pathology, in which the alpha-synuclein deposits cause damage and corresponding neurologic deficits.


title: Dementia with Lewy bodies

text: In DLB, there is an identifiable set of early signs and symptoms; these are called the prodromal, or pre-dementia, phase of the disease. These early signs and symptoms can appear 15 years or more before dementia develops. The earliest symptoms are constipation and dizziness from autonomic dysfunction, hyposmia (reduced ability to smell), RBD, anxiety, and depression. RBD may appear years or decades before other symptoms. Memory loss is not always an early symptom.


title: Dementia with Lewy bodies

text: Manifestations of DLB can be divided into essential, core, and supportive features. Dementia is the essential feature and must be present for diagnosis, while core and supportive features are further evidence in support of diagnosis (see diagnostic criteria below).


title: Dementia with Lewy bodies

text: A dementia diagnosis is made after cognitive decline progresses to a point of interfering with normal daily activities, or social or occupational function. While dementia is an essential feature of DLB, it does not always appear early on, and is more likely to be present as the condition progresses.


title: Dementia with Lewy bodies

text: While specific symptoms may vary, the core features of DLB are fluctuating cognition, alertness or attention; REM sleep behavior disorder; one or more of the cardinal features of parkinsonism, not due to medication or stroke; and repeated visual hallucinations.


title: Dementia with Lewy bodies

text: The 2017 "Fourth Consensus Report of the DLB Consortium" determined these to be core features based on the availability of high-quality evidence indicating they are highly specific to the condition.


title: Dementia with Lewy bodies

text: "Fluctuations" in cognitive function are the most characteristic feature of the Lewy body dementias. They are the most frequent symptom of DLB, and are often distinguishable from those of other dementias by concomitant fluctuations of attention and alertness, described by Tsamakis and Mueller (2021) as "spontaneous variations of cognitive abilities, alertness, or arousal". They are further distinguishable by a "marked amplitude between best and worst performances", according to McKeith (2002). These fluctuations vary in severity, frequency and duration; episodes last anywhere from seconds to weeks, interposed between periods of more normal functioning. When relatively lucid periods coincide with medical appointments, cognitive testing may inaccurately reflect disease severity, with subsequent assessments of cognition showing improvements from baseline.


title: Dementia with Lewy bodies

text: Unlike the deficits in memory and orientation that are characteristic of Alzheimer disease, the distinct impairments in cognition seen in DLB are most commonly in three domains: attention, executive function, and visuospatial function. These fluctuating impairments are present early in the course of the disease. Individuals with DLB may be easily distracted, have a hard time focusing on tasks, or appear to be "delirium-like", "zoning out", or in states of altered consciousness with spells of confusion, agitation or incoherent speech. They may have disorganized speech and their ability to organize their thoughts may change during the day.


title: Dementia with Lewy bodies

text: Executive function describes attentional and behavioral controls, memory and cognitive flexibility that aid problem solving and planning. Problems with executive function surface in activities requiring planning and organizing. Deficits can manifest in impaired job performance, inability to follow conversations, difficulties with multitasking, or mistakes in driving, such as misjudging distances or becoming lost.


title: Dementia with Lewy bodies

text: The person with DLB may experience disorders of wakefulness or sleep disorders (in addition to REM sleep behavior disorder) that can be severe. These disorders include daytime sleepiness, drowsiness or napping more than two hours a day, insomnia, periodic limb movements, restless legs syndrome and sleep apnea.


title: Dementia with Lewy bodies

text: REM sleep behavior disorder (RBD) is a parasomnia in which individuals lose the paralysis of muscles (atonia) that is normal during rapid eye movement (REM) sleep, and consequently act out their dreams or make other abnormal movements or vocalizations. About 80% of those with DLB have RBD. Abnormal sleep behaviors may begin before cognitive decline is observed, and may appear decades before any other symptoms, often as the first clinical indication of DLB and an early sign of a synucleinopathy. On autopsy, 94 to 98% of individuals with polysomnography-confirmed RBD have a synucleinopathy—most commonly DLB or Parkinson's disease in about equal proportions. More than three out of four people with RBD are diagnosed with a neurodegenerative condition within ten years, but additional neurodegenerative diagnoses may emerge up to 50 years after RBD diagnosis. RBD may subside over time.


title: Dementia with Lewy bodies

text: Individuals with RBD may not be aware that they act out their dreams. RBD behaviors may include yelling, screaming, laughing, crying, unintelligible talking, nonviolent flailing, or more violent punching, kicking, choking, or scratching. The reported dream enactment behaviors are frequently violent, and involve a theme of being chased or attacked. People with RBD may fall out of bed or injure themselves or their bed partners, which may cause bruises, fractures, or subdural hematomae. Because people are more likely to remember or report violent dreams and behaviors—and to be referred to a specialist when injury occurs—recall or selection bias may explain the prevalence of violence reported in RBD.


title: Dementia with Lewy bodies

text: Parkinsonism is a clinical syndrome characterized by slowness of movement (called "bradykinesia"), rigidity, postural instability, and tremor; it is found in DLB and many other conditions like Parkinson's disease, Parkinson's disease dementia, and others. Parkinsonism occurs in more than 85% of people with DLB, who may have one or more of these cardinal features, although tremor at rest is less common.


title: Dementia with Lewy bodies

text: Motor symptoms may include shuffling gait, problems with balance, falls, blank expression, reduced range of facial expression, and low speech volume or a weak voice. Presentation of motor symptoms is variable, but they are usually symmetric, presenting on both sides of the body. Only one of the cardinal symptoms of parkinsonism may be present, and the symptoms may be less severe than in persons with Parkinson's disease.


title: Dementia with Lewy bodies

text: Up to 80% of people with DLB have visual hallucinations, typically early in the course of the disease. They are recurrent and frequent; may be scenic, elaborate and detailed; and usually involve animated perceptions of animals or people, including children and family members. Examples of visual hallucinations "vary from 'little people' who casually walk around the house, 'ghosts' of dead parents who sit quietly at the bedside, to 'bicycles' that hang off of trees in the back yard".


title: Dementia with Lewy bodies

text: These hallucinations can sometimes provoke fear, although their content is more typically neutral. In some cases, the person with DLB has insight that the hallucinations are not real. Among those with more disrupted cognition, the hallucinations can become more complex, and they may be less aware that their hallucinations are not real.


title: Dementia with Lewy bodies

text: Visual misperceptions or illusions are also common in DLB but differ from visual hallucinations. While visual hallucinations occur in the absence of real stimuli, visual illusions occur when real stimuli are incorrectly perceived; for example, a person with DLB may misinterpret a floor lamp for a person.


title: Dementia with Lewy bodies

text: Supportive features of DLB have less diagnostic weight, but they provide evidence for the diagnosis. Supportive features may be present early in the progression, and persist over time; they are common but they are not specific to the diagnosis. The supportive features are:


title: Dementia with Lewy bodies

text: Partly because of loss of cells that release the neurotransmitter dopamine, people with DLB may have neuroleptic malignant syndrome, impairments in cognition or alertness, or irreversible exacerbation of parkinsonism including severe rigidity, and dysautonomia from the use of antipsychotics.


title: Dementia with Lewy bodies

text: Dysautonomia (autonomic dysfunction) occurs when Lewy pathology affects the peripheral autonomic nervous system (the nerves dealing with the unconscious functions of organs such as the intestines, heart, and urinary tract). The first signs of autonomic dysfunction are often subtle. Manifestations include blood pressure problems such as orthostatic hypotension (significantly reduced blood pressure upon standing) and supine hypertension (significantly elevated blood pressure when lying horizontally); constipation, urinary problems, and sexual dysfunction; loss of or reduced ability to smell; and excessive sweating, drooling, or salivation, and problems swallowing (dysphagia).


title: Dementia with Lewy bodies

text: Alpha-synuclein deposits can affect cardiac muscle and blood vessels. "Degeneration of the cardiac sympathetic nerves is a neuropathological feature" of the Lewy body dementias, according to Yamada Almost all people with synucleinopathies have cardiovascular dysfunction, although most are asymptomatic. Between of individuals with DLB have orthostatic hypotension due to reduced blood flow, which can result in lightheadedness, feeling faint, and blurred vision.


title: Dementia with Lewy bodies

text: From chewing to defecation, alpha-synuclein deposits affect every level of gastrointestinal function. Almost all persons with DLB have upper gastrointestinal tract dysfunction (such as gastroparesis, delayed gastric emptying) or lower gastrointestinal dysfunction (such as constipation and prolonged stool transit time). Persons with Lewy body dementia almost universally experience nausea, gastric retention, or abdominal distention from delayed gastric emptying. Problems with gastrointestinal function can affect medication absorption. Constipation can present a decade before diagnosis, and is one of the most common symptoms for people with Lewy body dementia. Dysphagia is milder than in other synucleinopathies and presents later. Urinary difficulties (urinary retention, waking at night to urinate, increased urinary frequency and urgency, and over- or underactive bladder) typically appear later and may be mild or moderate. Sexual dysfunction usually appears early in synucleinopathies, and may include erectile dysfunction and difficulty achieving orgasm or ejaculating.


title: Dementia with Lewy bodies

text: Among the other supportive features, psychiatric symptoms are often present when the individual first comes to clinical attention and are more likely, compared to AD, to cause more impairment. About one-third of people with DLB have depression, and they often have anxiety as well. Anxiety leads to increased risk of falls, and apathy may lead to less social interaction.


title: Dementia with Lewy bodies

text: Agitation, behavioral disturbances, and delusions typically appear later in the course of the disease. Delusions may have a paranoid quality, involving themes like a house being broken in to, infidelity, or abandonment. Individuals with DLB who misplace items may have delusions about theft. Capgras delusion may occur, in which the person with DLB loses knowledge of the spouse, caregiver, or partner's face, and is convinced that an imposter has replaced them. Hallucinations in other modalities are sometimes present, but are less frequent.


title: Dementia with Lewy bodies

text: Sleep disorders (disrupted sleep cycles, sleep apnea, and arousal from periodic limb movement disorder) are common in DLB and may lead to hypersomnia. Loss of sense of smell may occur several years before other symptoms.


title: Dementia with Lewy bodies

text: Like other synucleinopathies, the exact cause of DLB is unknown. No trigger for the build-up of alpha-synuclein deposits in the central nervous system has been conclusively identified. Synucleinopathies are typically caused by interactions of genetic and environmental influences; infectious causes have also been considered, but arguments in their favor are controversial and lacking in support. Most people with DLB do not have affected family members, although occasionally DLB runs in a family. The heritability of DLB is thought to be around 30% (that is, about 70% of disease severity is due to external factors or chance).


title: Dementia with Lewy bodies

text: There is overlap in the genetic risk factors for DLB, Alzheimer's disease (AD), Parkinson's disease, and Parkinson's disease dementia. The "APOE" gene has three common variants. One, "APOE" ε4, is a risk factor for DLB and Alzheimer's disease, whereas "APOE" ε2 may be protective against both. Mutations in "GBA", a gene for a lysosomal enzyme, are associated with both DLB and Parkinson's disease. Rarely, mutations in "SNCA", the gene for alpha-synuclein, or "LRRK2", a gene for a kinase enzyme, can cause any of DLB, Alzheimer's disease, Parkinson's disease or Parkinson's disease dementia. This suggests some shared genetic pathology may underlie all four diseases.


title: Dementia with Lewy bodies

text: The greatest risk of developing DLB is being over the age of 50. Having REM sleep behavior disorder or Parkinson's disease confers a higher risk for developing DLB. The risk of developing DLB has not been linked to any specific lifestyle factors. Risk factors for rapid conversion of RBD to a synucleinopathy include impairments in color vision or the ability to smell, mild cognitive impairment, and abnormal dopaminergic imaging.


title: Dementia with Lewy bodies

text: DLB is characterized by the development of abnormal collections of alpha-synuclein protein within diseased brain neurons, manifesting as Lewy bodies and Lewy neurites. When these clumps of protein form, neurons function less optimally and eventually die. Neuronal loss in DLB leads to profound dopamine dysfunction and marked cholinergic pathology; other neurotransmitters might be affected, but less is known about them. Damage in the brain is widespread, and affects many domains of functioning. Loss of acetylcholine-producing neurons is thought to account for degeneration in memory and learning, while the death of dopamine-producing neurons appears to be responsible for degeneration of behavior, cognition, mood, movement, motivation, and sleep. The extent of Lewy body neuronal damage is a key determinant of dementia in the Lewy body disorders.


title: Dementia with Lewy bodies

text: The precise mechanisms contributing to DLB are not well understood and are a matter of some controversy. The role of alpha-synuclein deposits is unclear, because individuals with no signs of DLB have been found on autopsy to have advanced alpha-synuclein pathology. The relationship between Lewy pathology and widespread cell death is contentious. It is not known if the pathology spreads between cells or follows another pattern. The mechanisms that contribute to cell death, how the disease advances through the brain, and the timing of cognitive decline are all poorly understood. There is no model to account for the specific neurons and brain regions that are affected.


title: Dementia with Lewy bodies

text: Autopsy studies and amyloid imaging studies using Pittsburgh compound B (PiB) indicate that tau protein pathology and amyloid plaques, which are hallmarks of AD, are also common in DLB and more common than in Parkinson's disease dementia. Amyloid-beta (Aβ) deposits are found in the tauopathies—neurodegenerative diseases characterized by neurofibrillary tangles of hyperphosphorylated tau protein—but the mechanism underlying dementia is often mixed, and Aβ is also a factor in DLB.


title: Dementia with Lewy bodies

text: A proposed pathophysiology for RBD implicates neurons in the reticular formation that regulate REM sleep. RBD might appear decades earlier than other symptoms in the Lewy body dementias because these cells are affected earlier, before spreading to other brain regions.


title: Dementia with Lewy bodies

text: Dementia with Lewy bodies can only be definitively diagnosed after death with an autopsy of the brain (or in rare familial cases, via a genetic test), so diagnosis of the living is referred to as "probable" or "possible".


title: Dementia with Lewy bodies

text: Diagnosing DLB can be challenging because of the wide range of symptoms with differing levels of severity in each individual. DLB is often misdiagnosed or, in its early stages, confused with Alzheimer's disease. The majority of individuals with Lewy body dementias receive an inaccurate initial diagnosis—such as Alzheimer's, parkinsonism, other dementias or a psychiatric diagnosis—resulting in reduced support and increased fear and uncertainty, sometimes for many years. Comparing the rates of detection of DLB in autopsy studies to those diagnosed while in clinical care indicates that as many as one in three diagnoses of DLB may be missed. Another complicating factor is that DLB commonly occurs along with Alzheimer's; autopsy reveals that half of people with DLB have some level of changes attributed to AD in their brains, which contributes to the wide-ranging variety of symptoms and diagnostic difficulty.


title: Dementia with Lewy bodies

text: Living with an uncertain diagnosis and prognosis is a concern expressed by both individuals with DLB and their caregivers and difficulty gaining a diagnosis and differing interactions with healthcare professionals are common experiences; once diagnosed, there are still difficulties finding a doctor knowledgeable in treating DLB. Despite the difficulty in diagnosis, a prompt diagnosis is important because of the serious risks of sensitivity to antipsychotics and the need to inform both the person with DLB and the person's caregivers about those medications' side effects. The management of DLB is difficult in comparison to many other neurodegenerative diseases, so an accurate diagnosis is important.


title: Dementia with Lewy bodies

text: The 2017 "Fourth Consensus Report" established diagnostic criteria for probable and possible DLB, recognizing advances in detection since the earlier "Third Consensus" (2005) version. The 2017 criteria are based on essential, core, and supportive clinical features, and diagnostic biomarkers.


title: Dementia with Lewy bodies

text: The essential feature is dementia; for a DLB diagnosis, it must be significant enough to interfere with social or occupational functioning.


title: Dementia with Lewy bodies

text: The four core clinical features (described in the "Signs and symptoms" section) are fluctuating cognition, visual hallucinations, REM sleep behavior disorder, and signs of parkinsonism. Supportive clinical features are marked sensitivity to antipsychotics; marked autonomic dysfunction; nonvisual hallucinations; hypersomnia (excessive sleepiness); hyposmia (reduced ability to smell); false beliefs and delusions organized around a common theme; postural instability, loss of consciousness and frequent falls; and apathy, anxiety, or depression.


title: Dementia with Lewy bodies

text: Direct laboratory-measurable biomarkers for DLB diagnosis are not known, but several indirect methods can lend further evidence for diagnosis. The indicative diagnostic biomarkers are: reduced dopamine transporter uptake in the basal ganglia shown on PET or SPECT imaging; low uptake of iodine-metaiodobenzylguanidine shown on myocardial scintigraphy; and loss of atonia during REM sleep evidenced on polysomnography. Supportive diagnostic biomarkers (from PET, SPECT, CT, or MRI brain imaging studies or EEG monitoring) are: lack of damage to medial temporal lobe (damage is more likely in AD); reduced occipital activity; and prominent slow-wave activity on EEG.


title: Dementia with Lewy bodies

text: Probable DLB can be diagnosed when dementia and at least two core features are present, or when one core feature and at least one indicative biomarker are present. Possible DLB can be diagnosed when dementia and only one core feature are present or, if no core features are present, then at least one indicative biomarker is present.


title: Dementia with Lewy bodies

text: DLB is distinguished from Parkinson's disease dementia by the time frame in which dementia symptoms appear relative to parkinsonian symptoms. DLB is diagnosed when cognitive symptoms begin before or at the same time as parkinsonian motor signs. Parkinson's disease dementia would be the diagnosis when Parkinson's disease is well established before the dementia occurs (the onset of dementia is more than a year after the onset of parkinsonian symptoms). Known as the "one-year rule", the distinction is acknowledged to be arbitrary; it recognizes overlap between the conditions along with key differences, while allowing for variations in treatment and prognosis and providing a framework for research.


title: Dementia with Lewy bodies

text: DLB is listed in the "Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition" (DSM-5) as major or mild neurocognitive disorder with Lewy bodies. The differences between the DSM and DLB Consortium diagnostic criteria are: 1) the DSM does not include low dopamine transporter uptake as a supportive feature, and 2) unclear diagnostic weight is assigned to biomarkers in the DSM. Lewy body dementias are classified by the World Health Organization in its ICD-10, the International Statistical Classification of Diseases and Related Health Problems, in chapter VI, as diseases of the nervous system, code 31.8.


title: Dementia with Lewy bodies

text: Diagnostic tests can be used to establish some features of the condition and distinguish them from symptoms of other conditions. Diagnosis may include taking the person's medical history, a physical exam, assessment of neurological function, brain imaging, neuropsychological testing to assess cognitive function, sleep studies, myocardial scintigraphy, or laboratory testing to rule out conditions that may cause symptoms similar to dementia, such as abnormal thyroid function, syphilis, HIV, and vitamin deficiencies.


title: Dementia with Lewy bodies

text: Typical dementia screening tests used are the Mini–Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA). The pattern of cognitive impairment in DLB is distinct from other dementias, such as AD; the MMSE mainly tests for the memory and language impairments more commonly seen in those other dementias and may be less suited for assessing cognition in the Lewy body dementias, where testing of visuospatial and executive function is indicated. The MoCA may be better suited to assessing cognitive function in DLB, and the Clinician Assessment of Fluctuation scale and the Mayo Fluctuation Composite Score may help understand cognitive decline relative to fluctuations in DLB. For tests of attention, digit span, serial sevens, and spatial span can be used for simple screening, and the Revised Digit Symbol Subtest of the Wechsler Adult Intelligence Scale may show defects in attention that are characteristic of DLB. The Frontal Assessment Battery, Stroop test and Wisconsin Card Sorting Test are used for evaluation of executive function, and there are many other screening instruments available.


title: Dementia with Lewy bodies

text: If DLB is suspected when parkinsonism and dementia are the only presenting features, PET or SPECT imaging may show reduced dopamine transporter activity. A DLB diagnosis may be warranted if other conditions with reduced dopamine transporter uptake can be ruled out.


title: Dementia with Lewy bodies

text: RBD is diagnosed either by sleep study recording or, when sleep studies cannot be performed, by medical history and validated questionnaires. In individuals with dementia and a history of RBD, a probable DLB diagnosis can be justified (even with no other core feature or biomarker) based on a sleep study showing REM sleep without atonia because it is so highly predictive. Conditions similar to RBD, like severe sleep apnea and periodic limb movement disorder, must be ruled out. Prompt evaluation and treatment of RBD is indicated when a prior history of violence or injury is present as it may increase the likelihood of future violent dream enactment behaviors. Individuals with RBD may not be able to provide a history of dream enactment behavior, so bed partners are also consulted. The REM Sleep Behavior Disorder Single-Question Screen offers diagnostic sensitivity and specificity in the absence of polysomnography with one question: "Have you ever been told, or suspected yourself, that you seem to 'act out your dreams' while asleep (for example, punching, flailing your arms in the air, making running movements, etc.)?" Because some individuals with DLB do not have RBD, normal findings from a sleep study cannot rule out DLB.


title: Dementia with Lewy bodies

text: Since 2001, iodine-metaiodobenzylguanidine myocardial scintigraphy has been used diagnostically in East Asia (principally Japan), but not in the US; studies validating its use in differential diagnoses are lacking as of 2022. MIBG is taken up by sympathetic nerve endings, such as those that innervate the heart, and is labeled for scintigraphy with radioactive iodine. Autonomic dysfunction resulting from damage to nerves in the heart in patients with DLB is associated with lower cardiac uptake of


title: Dementia with Lewy bodies

text: There is no genetic test to determine if an individual will develop DLB and, according to the Lewy Body Dementia Association, genetic testing is not routinely recommended because there are only rare instances of hereditary DLB.


title: Dementia with Lewy bodies

text: Many neurodegenerative conditions share cognitive and motor symptoms with dementia with Lewy bodies. The differential diagnosis includes Alzheimer's disease; such synucleinopathies as Parkinson's disease dementia, Parkinson's disease, and multiple system atrophy; vascular dementia; and progressive supranuclear palsy, corticobasal degeneration, and corticobasal syndrome.


title: Dementia with Lewy bodies

text: The symptoms of DLB are easily confused with delirium, or more rarely with psychosis; prodromal subtypes of delirium-onset DLB and psychiatric-onset DLB have been proposed. Mismanagement of delirium is a particular concern because of the risks to people with DLB associated with antipsychotics. A careful examination for features of DLB is warranted in individuals with unexplained delirium. PET or SPECT imaging showing reduced dopamine transporter uptake can help distinguish DLB from delirium.


title: Dementia with Lewy bodies

text: Lewy pathology affects the peripheral autonomic nervous system; autonomic dysfunction is observed less often in AD, frontotemporal, or vascular dementias, so its presence can help differentiate them. MRI scans almost always show abnormalities in the brains of people with vascular dementia, which can begin suddenly.


title: Dementia with Lewy bodies

text: DLB is distinguishable from AD even in the prodromal phase. Short-term memory impairment is seen early in AD and is a prominent feature, while fluctuating attention is uncommon; impairment in DLB is more often seen first as fluctuating cognition. In contrast to AD—in which the hippocampus is among the first brain structures affected, and episodic memory loss related to encoding of memories is typically the earliest symptom—memory impairment occurs later in DLB. People with amnestic mild cognitive impairment (in which memory loss is the main symptom) may progress to AD, whereas those with non-amnestic mild cognitive impairment (which has more prominent impairments in language, visuospatial, and executive domains) are more likely to progress towards DLB. Memory loss in DLB has a different progression from AD because frontal structures are involved earlier, with later involvement of temporoparietal brain structures. Verbal memory is not as severely affected as in AD.


title: Dementia with Lewy bodies

text: While 74% of people with autopsy-confirmed DLB had deficits in planning and organization, they show up in only 45% of people with AD. Visuospatial processing deficits are present in most individuals with DLB, and they show up earlier and are more pronounced than in AD. Hallucinations typically occur early in the course of DLB, are less common in early AD, but usually occur later in AD. AD pathology frequently co-occurs in DLB and is associated with more rapid decline; cerebrospinal fluid (CSF) testing may reveal an "Alzheimer's pattern" of higher tau and lower amyloid beta.


title: Dementia with Lewy bodies

text: PET or SPECT imaging can be used to detect reduced dopamine transporter uptake and distinguish AD from DLB. Severe atrophy of the hippocampus is more typical of AD than DLB. Before dementia develops (during the mild cognitive impairment phase), MRI scans show normal hippocampal volume. After dementia develops, MRI shows more atrophy among individuals with AD, and a slower reduction in volume over time among people with DLB than those with AD. Compared to people with AD, FDG-PET brain scans in people with DLB often show a cingulate island sign.


title: Dementia with Lewy bodies

text: In East Asia, particularly Japan, is used in the differential diagnosis of DLB and AD, because reduced labeling of cardiac nerves is seen only in Lewy body disorders. Other indicative and supportive biomarkers are useful in distinguishing DLB and AD (preservation of medial temporal lobe structures, reduced occipital activity, and slow-wave EEG activity).


title: Dementia with Lewy bodies

text: Dementia with Lewy bodies and Parkinson's disease dementia are clinically similar after dementia occurs in Parkinson's disease. Delusions in Parkinson's disease dementia are less common than in DLB, and persons with Parkinson's disease are typically less caught up in their visual hallucinations than those with DLB. There is a lower incidence of tremor at rest in DLB than in Parkinson's disease, and signs of parkinsonism in DLB are more symmetrical. In multiple system atrophy, autonomic dysfunction appears earlier and is more severe, and is accompanied by uncoordinated movements, while visual hallucinations and fluctuating cognition are less common than in DLB. Urinary difficulty is one of the earliest symptoms with multiple system atrophy, and is often severe.


title: Dementia with Lewy bodies

text: Corticobasal syndrome, corticobasal degeneration and progressive supranuclear palsy are frontotemporal dementias with features of parkinsonism and impaired cognition. Similar to DLB, imaging may show reduced dopamine transporter uptake. Corticobasal syndrome and degeneration, and progressive supranuclear palsy, are usually distinguished from DLB by history and examination. Motor movements in corticobasal syndrome are asymmetrical. There are differences in posture, gaze and facial expressions in the most common variants of progressive supranuclear palsy, and falling backwards is more common relative to DLB. Visual hallucinations and fluctuating cognition are unusual in corticobasal degeneration and progressive supranuclear palsy.


title: Dementia with Lewy bodies

text: Palliative care is offered to ameliorate symptoms, but there are no medications that can slow, stop, or improve the relentless progression of the disease. No medications for DLB are approved by the US Food and Drug Administration (FDA) as of 2020, although donepezil is licensed in Japan and the Philippines for the treatment of DLB. As of 2020, there has been little study on the best management for non-motor symptoms such as sleep disorders and autonomic dysfunction; most information on management of autonomic dysfunction in DLB is based on studies of people with Parkinson's disease.


title: Dementia with Lewy bodies

text: Management can be challenging because of the need to balance treatment of different symptoms: cognitive dysfunction, neuropsychiatric features, impairments related to the motor system, and other nonmotor symptoms. Individuals with DLB have widely different symptoms that fluctuate over time, and treating one symptom can worsen another; suboptimal care can result from a lack of coordination among the physicians treating different symptoms. A multidisciplinary approach—going beyond early and accurate diagnosis to include educating and supporting the caregivers—is favored.


title: Dementia with Lewy bodies

text: Pharmacological management of DLB is complex because of adverse effects of medications and the wide range of symptoms to be treated (cognitive, motor, neuropsychiatric, autonomic, and sleep). Anticholinergic and dopaminergic agents can have adverse effects or result in psychosis in individuals with DLB, and a medication that addresses one feature might worsen another. For example, acetylcholinesterase inhibitors (AChEIs) for cognitive symptoms can lead to complications in dysautonomia features; treatment of movement symptoms with dopamine agonists may worsen neuropsychiatric symptoms; and treatment of hallucinations and psychosis with antipsychotics may worsen other symptoms or lead to a potentially fatal reaction.


title: Dementia with Lewy bodies

text: Extreme caution is required in the use of antipsychotic medication in people with DLB because of their sensitivity to these agents. Severe and life-threatening reactions occur in almost half of people with DLB, and can be fatal after a single dose. Antipsychotics with D dopamine receptor-blocking properties are used only with great caution. According to Boot (2013), "electing not to use neuroleptics is often the best course of action". People with Lewy body dementias who take neuroleptics are at risk for neuroleptic malignant syndrome, a life-threatening illness. There is no evidence to support the use of antipsychotics to treat the Lewy body dementias, and they carry the additional risk of stroke when used in the elderly with dementia.


title: Dementia with Lewy bodies

text: Medications (including tricyclic antidepressants and treatments for urinary incontinence) with anticholinergic properties that cross the blood–brain barrier can cause memory loss. The antihistamine medication diphenhydramine (Benadryl), sleep medications like zolpidem, and benzodiazepines may worsen confusion or neuropsychiatric symptoms. Some general anesthetics may cause confusion or delirium upon waking in persons with Lewy body dementias, and may result in permanent decline.


title: Dementia with Lewy bodies

text: There is strong evidence for the use of AChEIs to treat cognitive problems; these medications include rivastigmine and donepezil. Both are first-line treatments in the UK. Even when the AChEIs do not lead to improvement in cognitive symptoms, people taking them may have less deterioration overall, although there may be adverse gastrointestinal effects. The use of these medications can reduce the burden on caregivers and improve activities of daily living for the individual with DLB. The AChEIs are initiated carefully as they may aggravate autonomic dysfunction or sleep behaviors. There is less evidence for the efficacy of memantine in DLB, but it may be used alone or with an AChEI because of its low side effect profile. Anticholinergic drugs are avoided because they worsen cognitive symptoms.


title: Dementia with Lewy bodies

text: To improve daytime alertness, there is mixed evidence for the use of stimulants such as methylphenidate and dextroamphetamine; although worsening of neuropsychiatric symptoms is not common, they can increase the risk of psychosis. Modafinil and armodafinil may be effective for daytime sleepiness.


title: Dementia with Lewy bodies

text: Motor symptoms in DLB appear to respond somewhat less to medications used to treat Parkinson's disease, like levodopa, and these medications can increase neuropsychiatric symptoms. Almost one out of every three individuals with DLB develops psychotic symptoms from levodopa. If such medications are needed for motor symptoms, cautious introduction with slow increases to the lowest possible dose may help avoid psychosis.


title: Dementia with Lewy bodies

text: The anticonvulsant zonisamide has been approved in Japan since 2009 for treating Parkinson's disease and since 2018 to treat parkinsonism in DLB. There is high certainty according to the GRADE certainty rating approach that it is effective for treating motor symptoms in DLB.


title: Dementia with Lewy bodies

text: Neuropsychiatric symptoms of DLB (aggression, anxiety, apathy, delusions, depression and hallucinations) do not always require treatment. The first line of defense in decreasing visual hallucinations is to reduce the use of dopaminergic drugs, which can worsen hallucinations. If new neuropsychiatric symptoms appear, the use of medications (such as anticholinergics, tricyclic antidepressants, benzodiazepines and opioids) that might be contributing to these symptoms is reviewed.


title: Dementia with Lewy bodies

text: Among the AChEIs, donepezil and rivastigmine can help reduce neuropsychiatric symptoms and improve the frequency and severity of hallucinations in the less severe stages of DLB. For treating psychosis and agitation in DLB, there is low evidence for memantine, olanzapine and aripiprazole, and very low evidence for the efficacy of quetiapine. Although clozapine has been shown effective in Parkinson's disease, there is very low evidence for its use to treat visual hallucinations in DLB, and its use requires regular blood monitoring.


title: Dementia with Lewy bodies

text: Apathy may be treated with AChEIs, and they may also reduce hallucinations, delusions, anxiety and agitation. Most medications to treat anxiety and depression have not been adequately investigated for DLB. Antidepressants may affect sleep and worsen RBD. Mirtazapine and SSRIs can be used to treat depression, depending on how well they are tolerated, and guided by general advice for the use of antidepressants in dementia. Antidepressants with anticholinergic properties may worsen hallucinations and delusions. People with Capgras syndrome may not tolerate AChEIs.


title: Dementia with Lewy bodies

text: The first steps in managing sleep disorders are to evaluate the use of medications that impact sleep and provide education about sleep hygiene. Sleep medications are carefully evaluated for each individual as they carry increased risk of falls, increased daytime sleepiness, and worsening cognition.


title: Dementia with Lewy bodies

text: Injurious dream enactment behaviors are a treatment priority. Frequency and severity of RBD may be lessened by treating sleep apnea, if it is present. RBD may be treated with melatonin or clonazepam. Melatonin may be more helpful in preventing injuries, and it offers a safer alternative, because clonazepam can produce deteriorating cognition, and worsen sleep apnea.


title: Dementia with Lewy bodies

text: Memantine is useful for some people. Modafinil may be used for hypersomnia, but no trials support its use in DLB. Antidepressants (SSRIs, SNRIs, tricyclics, and MAOIs), AChEIs, beta blockers, caffeine, and tramadol may worsen RBD.


title: Dementia with Lewy bodies

text: Decreasing the dosage of dopaminergic or atypical antipsychotic drugs may be needed with orthostatic hypotension, and high blood pressure drugs can sometimes be stopped. When non-pharmacological treatments for orthostatic hypotension have been exhausted, fludrocortisone, droxidopa, or midodrine are options, but these drugs have not been specifically studied for DLB as of 2020. Delayed gastric emptying can be worsened by dopaminergic medications, and constipation can be worsened by opiates and anticholinergic medications. Muscarinic antagonists used for urinary symptoms might worsen cognitive impairment in people with Lewy body dementias.


title: Dementia with Lewy bodies

text: There is no high-quality evidence for non-pharmacological management of DLB, but some interventions have been shown effective for addressing similar symptoms that occur in other dementias. For example, organized activities, music therapy, physical activity and occupational therapy may help with psychosis or agitation, while exercise and gait training can help with motor symptoms. Cognitive behavioral therapy can be tried for depression or hallucinations, although there is no evidence for its use in DLB. Cues can be used to help with memory retrieval.


title: Dementia with Lewy bodies

text: For autonomic dysfunction, several non-medication strategies may be helpful. Dietary changes include avoiding meals high in fat and sugary foods, eating smaller and more frequent meals, after-meal walks, and increasing fluids or dietary fiber to treat constipation. Stool softeners and exercise also help with constipation. Excess sweating can be helped by avoiding alcohol and spicy foods, and using cotton bedding and loose fitting clothing.


title: Dementia with Lewy bodies

text: Physical exercise in a sitting or recumbent position, and exercise in a pool, can help maintain conditioning. Compression stockings and elevating the head of the bed may also help, and increasing fluid intake or table salt can be tried to reduce orthostatic hypotension. To lessen the risk of fractures in individuals at risk for falls, bone mineral density screening and testing of vitamin D levels are used, and caregivers are educated on the importance of preventing falls. Physiotherapy has been shown helpful for Parkinson's disease dementia, but as of 2020, there is no evidence to support physical therapy in people with DLB.


title: Dementia with Lewy bodies

text: Demands placed on caregivers are higher than in AD because of the neuropsychiatric symptoms associated with DLB. Contributing factors to the caregiver burden in DLB are emotional fluctuations, apathy, psychosis, aggression, agitation, and night-time behaviors such as parasomnias, that lead to a loss of independence earlier than in AD. Caregivers may experience depression and exhaustion, and they may need support from other people. Other family members who are not present in the daily caregiving may not observe the fluctuating behaviors or recognize the stress on the caregiver, and conflict can result when family members are not supportive.


title: Dementia with Lewy bodies

text: Teaching caregivers how to manage neuropsychiatric symptoms (such as agitation and psychosis) is recommended, although education for caregivers has not been studied as thoroughly as in AD or Parkinson's disease. Caregiver education reduces not only distress for the caregiver, but symptoms for the individual with dementia. Caregiver training, watchful waiting, identifying sources of pain, and increasing social interaction can help minimize agitation. Individuals with dementia may not be able to communicate that they are in pain, and pain is a common trigger of agitation.


title: Dementia with Lewy bodies

text: Visual hallucinations associated with DLB create a particular burden on caregivers. Caregivers can be educated to distract or change the subject when confronted with hallucinations, and that this is more effective than arguing over the reality of the hallucination. Coping strategies may help and are worth trying, even though there is no evidence for their efficacy. These strategies include having the person with DLB look away or look at something else, focus on or try to touch the hallucination, wait for it to go away on its own, and speak with others about the visualization. Delusions and hallucinations may be reduced by increasing lighting in the evening, and making sure there is no light at night when the individual with DLB is sleeping.


title: Dementia with Lewy bodies

text: With the increased risk of side effects from antipsychotics for people with DLB, educated caregivers are able to act as advocates for the person with DLB. If evaluation or treatment in an emergency room is needed, the caregiver may be able to explain the risks associated with neuroleptic use for persons with DLB. Medical alert bracelets or notices about medication sensitivity are available and can save lives.


title: Dementia with Lewy bodies

text: Individuals and their caregivers can be counselled about the need to improve bedroom safety for RBD symptoms. Sleep-related injuries from falling or jumping out of bed can be avoided by lowering the height of the bed, placing a mattress next to the bed to soften the impact of a fall, and removing sharp objects from around the bed. Sharp surfaces near the bed can be padded, bed alarm systems may help with sleepwalking, and bed partners may find it safer to sleep in another room. According to St Louis and Boeve, firearms should be locked away, out of the bedroom.


title: Dementia with Lewy bodies

text: A home safety assessment can be done when there is risk of falling. Handrails and shower chairs can help avoid falls. Driving ability may be impaired early in DLB because of visual hallucinations, movement issues related to parkinsonism, and fluctuations in cognitive ability, and at some point it becomes unsafe for the person to drive. Driving ability is assessed as part of management, and family members generally determine when driving privileges are removed.


title: Dementia with Lewy bodies

text: As of 2021, no cure is known for DLB. The prognosis for DLB has not been well studied; early studies had methodological limitations, such as small sample size and selection bias. Relative to AD and other dementias, DLB generally leads to higher rates of disability, hospitalization and institutionalization, and lower life expectancy and quality of life, with increased costs of care. Depression, apathy, and visual hallucinations contribute to the reduced quality of life. Decline may be more rapid when the "APOE" gene is present, or when AD—or its biomarkers—is also present. The severity of orthostatic hypotension also predicts a worse prognosis. Visuospatial deficits early in the course of DLB were thought to be a predictor of rapid decline, but more recent studies did not find an association.


title: Dementia with Lewy bodies

text: The trajectory of cognitive decline in DLB is difficult to establish because of the high rate of missed diagnoses; the typical delay of a year in the US, and 1.2 years in the UK, for diagnosis of DLB mean that a baseline from which deterioration can be measured is often absent. Compared to AD, which is better studied, memory is thought to be retained longer, while verbal fluency may be lost faster, but the most common tools used to assess cognition may miss the most common cognitive deficits in DLB, and better studies are needed.


title: Dementia with Lewy bodies

text: There are more neuropsychiatric symptoms in DLB than AD, and they may emerge earlier, so those with DLB may have a less favorable prognosis, with more rapid cognitive decline, more admissions to residential care, and a lower life expectancy. An increased rate of hospitalization compared to AD is most commonly related to hallucinations and confusion, followed by falls and infection.


title: Dementia with Lewy bodies

text: Life expectancy is difficult to predict, and limited study data are available. Survival may be defined from the point of disease onset, or from the point of diagnosis. There is wide variability in survival times, and as DLB may be rapidly or slowly progressing. A 2019 meta-analysis found an average survival time after diagnosis of 4.1 years—indicating survival in DLB 1.6 years less than after a diagnosis of Alzheimer's. A 2017 review found survival from disease onset between 5.5 and 7.7 years, and survival from diagnosis between 1.9 and 6.3 years. The difference in survival between AD and DLB could be because DLB is harder to diagnose, and may be diagnosed later in the course of the disease. An online survey with 658 respondents found that, after diagnosis, more than 10% died within a year, 10% lived more than 7 years, and some live more than 10 years; some people with Lewy body dementias live for 20 years. Shorter life expectancy is more likely when visual hallucinations, abnormal gait, and variable cognition are present early on.


title: Dementia with Lewy bodies

text: Fear and anxiety feature strongly for both people with Lewy body dementia and their caregivers; a range of emotional responses to living with Lewy bodies includes fear of hallucinations, fear of falls and frightening nightmares as a result of RBD, and being scared of the effects of tiredness and fatigue. The symptoms of fluctuations, depression, delirium and violence are also experienced as frightening. An immense amount of physical support from friends and family is often required to maintain social and supporting relationships. Individuals with Lewy body dementias describe feeling a burden in the wider social context, as they reduce attending social events due to their increasing physical needs. Frequently reported burden dimensions include personal strain and interference with personal life, which can lead to relationship dissatisfaction and resentment.


title: Dementia with Lewy bodies

text: In the late part of the disease, people may be unable to care for themselves. Falls—caused by many factors including parkinsonism, dysautonomia, and frailness—increase morbidity and mortality. Failure to thrive and aspiration pneumonia, a complication of dysphagia (difficulty swallowing) that results from dysautonomia, commonly cause death among people with the Lewy body dementias. Cardiovascular disease and sepsis are also common causes of death.


title: Dementia with Lewy bodies

text: The Lewy body dementias are as a group the second most common form of neurodegenerative dementia after AD as of 2021. DLB itself is one of the three most common types of dementia, along with AD and vascular dementia.


title: Dementia with Lewy bodies

text: The diagnostic criteria for DLB before 2017 were highly specific, but not very sensitive, so that more than half of cases were missed historically. Dementia with Lewy bodies was under-recognized as of 2021, and there is little data on its epidemiology. The incidence and prevalence of DLB are not known accurately, but estimates are increasing with better recognition of the condition since 2017.


title: Dementia with Lewy bodies

text: About 0.4% of those over the age of 65 are affected with DLB, and between per 1,000 people develop the condition each year. Symptoms usually appear between the ages of 50 and 80 (median 76), and it is not uncommon for it to be diagnosed before the age of 65. DLB is thought to be slightly more common in men than women, but a 2014 review challenged that view, and said that the gender distribution was unclear. An estimated 10 to 15% of diagnosed dementias are Lewy body type, but estimates range as high as 23% for those in clinical studies.


title: Dementia with Lewy bodies

text: A French study found an incidence among persons 65 years and older almost four times higher than a US study per 100,000 person-years), but the US study may have excluded people with only mild or no parkinsonism, while the French study screened for parkinsonism. Neither of the studies assessed systematically for RBD, so DLB may have been underdiagnosed in both studies. A door-to-door study in Japan found a prevalence of 0.53% for persons 65 and older, and a Spanish study found similar results.


title: Dementia with Lewy bodies

text: Frederic Lewy (1885–1950) was the first to discover the abnormal protein deposits in the early 1900s. In 1912, studying Parkinson's disease ("paralysis agitans"), he described findings of these inclusion bodies in the vagus nerve, the nucleus basalis of Meynert and other brain regions. He published a book, "The Study on Muscle Tone and Movement. Including Systematic Investigations on the Clinic, Physiology, Pathology, and Pathogenesis of Paralysis agitans", in 1923 and except for one brief paper a year later, never mentioned his findings again.


title: Dementia with Lewy bodies

text: In 1961, Okazaki "et al." published an account of diffuse Lewy-type inclusions associated with dementia in two autopsied cases. Dementia with Lewy bodies was fully described in an autopsied case by Japanese psychiatrist and neuropathologist Kenji Kosaka in 1976. Kosaka first proposed the term "Lewy body disease" four years later, based on 20 autopsied cases. DLB was thought to be rare until it became easier to diagnose in the 1980s after the discovery of alpha-synuclein immunostaining that highlighted Lewy bodies in post mortem brains. described thirty-four more cases in 1984, which were mentioned along with four UK cases by in 1987 in the journal "Brain", bringing attention of the Japanese work to the Western world. A year later, published the first general description of diffuse Lewy body disease.


title: Dementia with Lewy bodies

text: With Japanese, UK, and US researchers finding in the 1990s that DLB was a common dementia, there were nonetheless no diagnostic guidelines, and each group was using different terminology. The different groups of researchers began to realize that a collaborative approach was needed if research was to advance. The DLB Consortium was established, and in 1996, the term "dementia with Lewy bodies" was agreed upon and the first criteria for diagnosing DLB were elaborated.


title: Dementia with Lewy bodies

text: Two 1997 discoveries highlighted the importance of Lewy body inclusions in neurodegenerative processes: a mutation in the "SNCA" gene that encodes the alpha-synuclein protein was found in kindreds with Parkinson's disease, and Lewy bodies and neurites were found to be immunoreactive for alpha-synuclein. Thus, alpha-synuclein aggregation as the primary building block of the synucleinopathies was established.


title: Dementia with Lewy bodies

text: Between 1995 and 2005, the DLB Consortium issued three Consensus Reports on DLB. DLB was included in the fourth text revision of the DSM (DSM-IV-TR, published in 2000) under "Dementia due to other general medical conditions". In the 2010s, the possibility of a genetic basis began to emerge. The Fourth Consensus Report was issued in 2017, giving increased diagnostic weighting to RBD and myocardial scintigraphy.


title: Dementia with Lewy bodies

text: The British author and poet Mervyn Peake died in 1968 and was diagnosed posthumously as a probable case of DLB in a 2003 study published in "JAMA Neurology". Based on signs in his work and letters of progressive deterioration, fluctuating cognitive decline, deterioration in visuospatial function, declining attention span, and visual hallucinations and delusions, his may be the earliest known case where DLB was found to have been the likely cause of death.


title: Dementia with Lewy bodies

text: At the time of his suicide on August 11, 2014, Robin Williams, the American actor and comedian, had been diagnosed with Parkinson's disease. According to his widow, Williams had experienced depression, anxiety, and increasing paranoia. His widow said that his autopsy found diffuse Lewy body disease, while the autopsy used the term "diffuse Lewy body dementia". Dennis Dickson, a spokesperson for the Lewy Body Dementia Association, clarified the distinction by stating that "diffuse Lewy body dementia" is more commonly called "diffuse Lewy body disease" and refers to the underlying disease process. According to Dickson, "Lewy bodies are generally limited in distribution, but in DLB, the Lewy bodies are spread widely throughout the brain, as was the case with Robin Williams." Ian G. McKeith, professor and researcher of Lewy body dementias, commented that Williams' symptoms and autopsy findings were explained by DLB.


title: Dementia with Lewy bodies

text: The identification of prodromal biomarkers for DLB will enable treatments to begin sooner, improve the ability to select subjects and measure efficacy in clinical trials, and help families and clinicians plan for early interventions and awareness of potential adverse effects from the use of antipsychotics. Criteria were established in 2020 to help researchers better recognize DLB in the pre-dementia phase. Three syndromes of prodromal DLB have been proposed: 1) mild cognitive impairment with Lewy bodies (MCI-LB); 2) delirium-onset DLB; and 3) psychiatric-onset DLB. The three early syndromes may overlap. As of 2020, the DLB Diagnostic Study Group's position is that criteria for MCI-LB can be recommended, but that it remains difficult to distinguish delirium-onset and psychiatric-onset DLB without better biomarkers. Nonetheless, severe late-onset psychiatric disorders can be an indication to consider Lewy body dementia, and unexplained delirium raises the possibility of prodromal DLB.


title: Dementia with Lewy bodies

text: The diagnosis of DLB is made using the DLB Consortium criteria, but a 2017 study of skin samples from 18 people with DLB found that all of them had deposits of phosphorylated alpha-synuclein, while none of the controls did, suggesting that skin samples offer diagnostic potential. Other potential biomarkers under investigation are quantitative electroencephalography, imaging examination of brain structures, and measures of synucleinopathy in CSF. While commercial skin biopsy tests for DLB are available in the US, and the FDA has given a 'breakthrough device' authorization for CSF testing, these tests are not widely available and their role in clinical practice has not been established as of 2022. Other tests to detect alpha-synuclein with blood tests are under study as of 2021.


title: Dementia with Lewy bodies

text: Cognitive training, deep brain stimulation and transcranial direct-current stimulation have been studied more in Parkinson's and Alzheimer's disease than they have in dementia with Lewy bodies, and all are potential therapies for DLB. Four clinical trials for treating parkinsonian symptoms in DLB have been completed as of 2021, but more studies are needed to assess risk vs. benefits, adverse effects, and longer-term usage.


title: Dementia with Lewy bodies

text: Strategies for future intervention involve modifying the course of the disease using immunotherapy, gene therapy, and stem cell therapy, and reducing amyloid beta or alpha-synuclein accumulation. Therapies under study as of 2019 aim to reduce brain levels of alpha-synuclein (with the pharmaceuticals ambroxol, NPT200-11, and E2027) or to use immunotherapy to reduce widespread neuroinflammation resulting from alpha-synuclein deposits.


title: Srinidhi Shetty

text: Srinidhi Ramesh Shetty (born 21 October 1992) is an Indian actress, model and the winner of the Miss Supranational 2016 pageant. Shetty was crowned as Miss Diva Supranational 2016 at the Miss Diva 2016 pageant and later represented India at Miss Supranational 2016, which she won. She is the second Indian representative to have won this title. Shetty made her acting debut with the Kannada film "" (2018).


title: Srinidhi Shetty

text: Srinidhi Ramesh Shetty was born on 21 October 1992, in a Mangalorean family of Tuluvers belonging to the Bunt. Her father Ramesh Shetty is from the town of Mulki, and her mother Kushala is from Thalipady Guthu, Kinnigoli.


title: Srinidhi Shetty

text: She was educated at Sri Narayana Guru English Medium School, followed by a pre-university course at St. Aloysius Pre-University College. She received a Bachelor of Electrical Engineering degree from Jain University, Bangalore, and graduated with distinction.


title: Srinidhi Shetty

text: In 2012, Srinidhi competed in the Clean & Clear-sponsored Fresh Face contest, where she was among the top two finalists. Later, she participated in Manappuram Miss South India in 2015 and won the titles of Miss Karnataka and Miss Beautiful Smile, and later participated in Manappuram Miss Queen of India where she was crowned as the 1st runner up and also named Miss Congeniality. She also worked as a model while employed at Accenture.


title: Srinidhi Shetty

text: In 2016, she participated in the 2016 Miss Diva pageant, where she was selected as a finalist and won the Miss Supranational India 2016 title. She also won three subtitles for her smile, body and her photogenic face. She went on to represent India at Miss Supranational 2016. On 2 December 2016, she was crowned Miss Supranational 2016 by her predecessor Stephania Stegman of Paraguay in Municipal Sports and Recreation Center, Krynica-Zdrój, Poland. She also won the title of Miss Supranational Asia and Oceania 2016 in the pageant.


title: Srinidhi Shetty

text: During her reign as Miss Supranational 2016, Srinidhi traveled to United Arab Emirates, France, Japan, Singapore, Thailand, Slovakia and numerous trips around Poland and India.


title: Srinidhi Shetty

text: Shetty made her acting debut with the 2018 Kannada period action film, "" opposite Yash. It was directed by Prashanth Neel. She portrayed a head strong girl, Reena Desai. The performances of every actor was praised. The film was a box office success, grossing ₹250 crore.


title: Srinidhi Shetty

text: In 2022, she reprised her role of Reena in the film's sequel, "". Shetty's character received negative reviews, while the film received positive review. "India Today" found the role to be "quite disappointing and problematic." With earnings of ₹1,200–1,250 crore globally, it is the highest grossing Indian film of 2022 and third highest-grossing Indian film. The same year, she made her Tamil debut with action thriller film "Cobra" alongside Vikram. The film was a box-office bomb collecting ₹40 crore. Shetty portrayed Bhavana Menon, a criminology professor, "India Today" said her character was "insignificant".


title: Chief Keef

text: Keith Farrelle Cozart (born August 15, 1995), better known by his stage name Chief Keef, is an American rapper, singer, songwriter and record producer. His music first became popular during his teen years in the early 2010s among high school students from Chicago's South Side. In 2012, his popular local single "I Don't Like" was remixed by American rapper Kanye West and reached the "Billboard" Rap Top 20, further raising Cozart's profile. A bidding war between major labels resulted in Keef signing with Interscope. His debut album "Finally Rich" was released in December 2012, and featured the singles "I Don't Like" and "Love Sosa", which would popularize the Chicago rap subgenre drill.


title: Chief Keef

text: Chief Keef has faced ongoing legal issues during his career, including weapons possession charges, house arrest sentences, and a performance ban imposed by Chicago authorities. Though he was dropped from Interscope in late 2014 and later signed to 1017 Records, he continued self-releasing projects through his own Glo Gang label. These included: "Nobody" (2014), "Back from the Dead 2" (2014), "Bang 3" (2015), and "Thot Breaker" (2017).


title: Chief Keef

text: As of the late 2010s, critics have pointed to Chief Keef as the progenitor of the drill subgenre, noting the impact of his music on other artists.


title: Chief Keef

text: Chief Keef was born Keith Farrelle Cozart in Chicago, Illinois, on August 15, 1995, to Lolita Carter who was 15 and unwed. He is named after his deceased uncle, Keith Carter, who was known as "Big Keef". He lived at the Parkway Garden Homes located in the Washington Park neighborhood on the city's South Side, a stronghold for the Black Disciples street gang of which Chief Keef is a member.


title: Chief Keef

text: Chief Keef has been estranged from his biological father, Alfonso Cozart, since he was a minor. His legal guardian was his grandmother with whom he lived in Chicago. He began rapping as a five-year-old using his mother's karaoke machine and tapes to record his music. During his childhood, Chief Keef attended Dulles Elementary School and the Banner School, a therapeutic day school. He dropped out of Dyett High School at age 15.


title: Chief Keef

text: In 2011, Chief Keef first attracted local attention from Chicago's South Side community with his mixtapes, "The Glory Road" and "Bang". In December, he was arrested for firing a gun from his car in Chicago's Washington Park neighborhood; he was placed under house arrest at his grandmother's residence for 30 days, followed by another 30 days of home confinement. While under house arrest, he posted several videos to his YouTube account, forerunners to Chicago's hip hop subgenre, drill.


title: Chief Keef

text: Keef's song "I Don't Like" became a hit in Chicago. A local party promoter called it "the perfect Chicago song because 'niggas just hate everything out here'". It caught Kanye West's attention, and he remixed the song with rappers Pusha T, Jadakiss and Big Sean. As a result, Keef "suddenly shot up out of obscurity".


title: Chief Keef

text: In the summer of 2012, Chief Keef was the subject of a bidding war among record labels wishing to sign him, including Young Jeezy's CTE World. While 2012 proved to be a relatively quiet year in terms of his musical output, Chief Keef began the year by signing with Interscope Records. In a separate deal, he was promised his own label imprint, Glory Boyz Entertainment (GBE). The deal was worth $6,000,000 over a three album layout, with an additional $440,000 advance to establish GBE.


title: Chief Keef

text: The deal gave Interscope the right to pull out of the contract if Chief Keef's debut album "Finally Rich", released on December 18, 2012, had failed to sell 250,000 copies by December 2013. Featured guests on the album include rappers: 50 Cent, Wiz Khalifa, Young Jeezy, Rick Ross and his fellow Glory Boyz member Lil Reese. In May 2013 he signed with 1017 Brick Squad Records.


title: Chief Keef

text: Chief Keef is featured on "Hold My Liquor", the fifth track on Kanye West's album, "Yeezus", released on June 18, 2013. Keef's contributions to the track were praised by musician Lou Reed who said, "'Hold My Liquor' is just heartbreaking, and particularly coming from where it's coming from – listen to that incredibly poignant hook from a tough guy like Chief Keef, wow."


title: Chief Keef

text: On his 18th birthday, August 15, 2013, Chief Keef celebrated by releasing the mixtape "Bang, Pt. 2". It was highly anticipated as the first project following his debut album, but received a mixed to negative critical response. On October 12, 2013, another mixtape, "Almighty Sosa", was released. Like "Bang, Pt. 2", "Almighty So" also received mixed to negative critical reviews. After serving his October 2013 jail term (see § Legal issues), he began working on his second studio album and a biopic.