This is a heterozygous familial hypercholesterolemia. We must know how to recognize the disease and know the criteria. It seems to me to be of high difficulty.

A 34-year-old man referred to the clinic for persistent LDL cholesterol levels above 250 mg/dL. The patient is asymptomatic but on examination there are whitish indurated spots on elbows, knees and eyelids. His BP is 135/85 mmHg. Her father died of myocardial infarction at the age of 48 years. The fasting blood test shows a total cholesterol of 346 mg/dl, LDL cholesterol of 278 mg/dl, HDL cholesterol of 42 mg/dl, triglycerides of 130 mg/dl and glucose of 93 mg/dl. Regarding the disease from which this patient suffers, one of the following statements is FALSE. Point out which one:

It is an autosomal codominant hereditary disease, with a high penetrance, so it is frequent that some of the parents and siblings of the individual also suffer from it.

The genetic disorder affects the gene encoding the LDL cholesterol receptor and more than 900 mutations have been described.

The genetic disorder also affects the synthesis of triglycerides, causing in the advanced stages of the disease, an increase in triglycerides, which is usually higher than 500 mg/dl.

Untreated males have a near 50% chance of a coronary event before age 60, and women with the disease have a higher prevalence of ischemic heart disease than the general female population.

Statins are effective in the treatment of the heterozygous form of the disease, but often need to be combined with cholesterol absorption inhibitors to achieve therapeutic goals and disease control.

Diagnosis of families with familial hypercholesterolaemia and/or Apo B-100 defect by means of DNA analysis of LDL-receptor gene mutations.

One major problem of using hypercholesterolaemia alone as a primary criterion for diagnosing familial hypercholesterolaemia (FH) is that 15-40% of relatives may be misdiagnosed because plasma lipid levels in FH heterozygotes overlap with those in the general population. General Hospital/University of Vienna, Department of Pediatrics, Outpatient lipid clinic. As a part of the MED-PED (make early diagnosis-prevent early death) project we are currently investigating children, adolescents and their relatives who are suspected to be affected with FH in our out-patient clinic for metabolic diseases using MED-PED inclusion criteria and confirming the diagnosis by means of DNA analysis. 263 patients with premature atherosclerosis and/or hypercholesterolaemia: 116 children (mean age 11.6 +/- 4.1 years; 57 girls and 59 boys) and 147 adults (64 women, mean age 41.5 +/- 13.7 years; 83 men, mean age 42.8 +/- 10.8 years). 119 patients with mutations have been detected; 56 children with either low density lipoprotein receptor (LDLR) and/or ApoB mutations (27 girls and 29 boys; mean total cholesterol (TC) 275 +/- 71 mg/dl, triglycerides (TG) 101 +/- 57 mg/dl, high-density lipoprotein cholesterol (HDL-C) 49 +/- 12 mg/dl, low-density lipoprotein cholesterol (LDL-C) 198 +/- 67 mg/dl) and one boy with a homozygous. LDLR mutation. A further 62 adults with LDLR and/or ApoB mutations were documented; 33 women (mean age 36.9 +/- 11.1 years; mean TC 283 +/- 76 mg/dl, TG 137 +/- 78 mg/dl, HDL-C 55 +/- 17 mg/dl, LDL-C 210 +/- 67 mg/dl) and 29 men (mean age 45.0 +/- 10.6 years; mean TC 301 +/- 87 mg/dl, TG 163 +/- 112 mg/dl, HDL-C 42 +/- 12 mg/dl, LDL-C 233 +/- 83 mg/dl). In 32 of these subjects (11 children (21%), 21 adults (42%)), serum lipid levels were lower than the diagnostic MED-PED limits adopted, so that they might have been misclassified without an additional DNA analysis. In our study, diagnosis of FH and related disorders (ApoB-100 defect) by means of conventional laboratory methods missed at least 21% in children and 42% in adults affected with LDLR and/or ApoB gene mutations. Genetic FH diagnosis provides a tool for specific diagnosis of mutation carrier status.

Low-density lipoprotein apheresis: an evidence-based analysis.

To assess the effectiveness and safety of low-density lipoprotein (LDL) apheresis performed with the heparin-induced extracorporeal LDL precipitation (HELP) system for the treatment of patients with refractory homozygous (HMZ) and heterozygous (HTZ) familial hypercholesterolemia (FH).  BACKGROUND ON FAMILIAL HYPERCHOLESTEROLEMIA: Familial hypercholesterolemia is a genetic autosomal dominant disorder that is caused by several mutations in the LDL-receptor gene. The reduced number or absence of functional LDL receptors results in impaired hepatic clearance of circulating low-density lipoprotein cholesterol (LDL-C) particles, which results in extremely high levels of LDL-C in the bloodstream. Familial hypercholesterolemia is characterized by excess LDL-C deposits in tendons and arterial walls, early onset of atherosclerotic disease, and premature cardiac death. Familial hypercholesterolemia occurs in both HTZ and HMZ forms. Heterozygous FH is one of the most common monogenic metabolic disorders in the general population, occurring in approximately 1 in 500 individuals. Nevertheless, HTZ FH is largely undiagnosed and an accurate diagnosis occurs in only about 15% of affected patients in Canada. Thus, it is estimated that there are approximately 3,800 diagnosed and 21,680 undiagnosed cases of HTZ FH in Ontario. In HTZ FH patients, half of the LDL receptors do not work properly or are absent, resulting in plasma LDL-C levels 2- to 3-fold higher than normal (range 7-15mmol/L or 300-500mg/dL). Most HTZ FH patients are not diagnosed until middle age when either they or one of their siblings present with symptomatic coronary artery disease (CAD). Without lipid-lowering treatment, 50% of males die before the age of 50 and 25% of females die before the age of 60, from myocardial infarction or sudden death. In contrast to the HTZ form, HMZ FH is rare (occurring in 1 case per million persons) and more severe, with a 6- to 8-fold elevation in plasma LDL-C levels (range 15-25mmol/L or 500-1000mg/dL). Homozygous FH patients are typically diagnosed in infancy, usually due to the presence of cholesterol deposits in the skin and tendons. The main complication of HMZ FH is supravalvular aortic stenosis, which is caused by cholesterol deposits on the aortic valve and in the ascending aorta. The average life expectancy of affected individuals is 23 to 25 years. In Ontario, it is estimated that there are 13 to 15 cases of HMZ FH. An Ontario clinical expert confirmed that 9 HMZ FH patients have been identified to date. There are 2 accepted clinical diagnostic criterion for the diagnosis of FH: the Simon Broome FH Register criteria from the United Kingdom and the Dutch Lipid Network criteria from the Netherlands. The criterion supplement cholesterol levels with clinical history, physical signs and family history. DNA-based-mutation-screening methods permit a definitive diagnosis of HTZ FH to be made. However, given that there are over 1000 identified mutations in the LDL receptor gene and that the detection rates of current techniques are low, genetic testing becomes problematic in countries with high genetic heterogeneity, such as Canada. The primary aim of treatment in both HTZ and HMZ FH is to reduce plasma LDL-C levels in order to reduce the risk of developing atherosclerosis and CAD. The first line of treatment is dietary intervention, however it alone is rarely sufficient for the treatment of FH patients. Patients are frequently treated with lipid-lowering drugs such as resins, fibrates, niacin, statins and cholesterol absorption-inhibiting drugs (ezetimibe). Most HTZ FH patients require a combination of drugs to achieve or approach target cholesterol levels. A small number of HTZ FH patients are refractory to treatment or intolerant to lipid-lowering medication. According to clinical experts, the prevalence of refractory HTZ FH in Ontario is between 1 to 5%. Using the mean of 3%, it is estimated that there are approximately 765 refractory HTZ FH patients in Ontario, of which 115 are diagnosed and 650 are undiagnosed. Drug therapy is less effective in HMZ FH patients since the effects of the majority of cholesterol-lowering drugs are mediated by the upregulation of LDL receptors, which are often absent or function poorly in HMZ FH patients. Some HMZ FH patients may still benefit from drug therapy, however this rarely reduces LDL-C levels to targeted levels.  EXISTING TECHNOLOGY: PLASMA EXCHANGE An option currently available in Ontario for FH patients who do not respond to standard diet and drug therapy is plasma exchange (PE). Patients are treated with this lifelong therapy on a weekly or biweekly basis with concomitant drug therapy. Plasma exchange is nonspecific and eliminates virtually all plasma proteins such as albumin, immunoglobulins, coagulation factors, fibrinolytic factors and HDL-C, in addition to acutely lowering LDL-C by about 50%. Blood is removed from the patient, plasma is isolated, discarded and replaced with a substitution fluid. The substitution fluid and the remaining cellular components of the blood are then returned to the patient. The major limitation of PE is its nonspecificity. The removal of HDL-C prevents successful vascular remodeling of the areas stenosed by atherosclerosis. In addition, there is an increased susceptibility to infections, and costs are incurred by the need for replacement fluid. Adverse events can be expected to occur in 12% of procedures.  OTHER ALTERNATIVES: Surgical alternatives for FH patients include portocaval shunt, ileal bypass and liver transplantation. However, these are risky procedures and are associated with a high morbidity rate. Results with gene therapy are not convincing to date. LDL APHERESIS An alternative to PE is LDL apheresis. Unlike PE, LDL apheresis is a selective treatment that removes LDL-C and other atherogenic lipoproteins from the blood while minimally impacting other plasma components such as HDL-C, total serum protein, albumin and immunoglobulins. As with PE, FH patients require lifelong therapy with LDL apheresis on a weekly/biweekly basis with concomitant drug therapy.  HEPARIN-INDUCED EXTRACORPOREAL LDL PRECIPITATION: Heparin-induced extracorporeal LDL precipitation (HELP) is one of the most widely used methods of LDL apheresis. It is a continuous closed-loop system that processes blood extracorporeally. It operates on the principle that at a low pH, LDL and lipoprotein (a) [Lp(a)] bind to heparin and fibrinogen to form a precipitate which is then removed by filtration. In general, the total duration of treatment is approximately 2 to 3 hours. Results from early trials indicate that LDL-C concentration is reduced by 65% to 70% immediately following treatment in both HMZ and HTZ FH and then rapidly begins to rise. Typically patients with HTZ FH are treated every 2 weeks while patients with HMZ FH require weekly therapy. Heparin-induced extracorporeal LDL precipitation also produces small transient decreases in HDL-C, however levels generally return to baseline within 2 days. After several months of therapy, long-term reductions in LDL-C and increases in HDL-C have been reported. In addition to having an impact on plasma cholesterol concentrations, HELP lowers plasma fibrinogen, a risk factor for atherosclerosis, and reduces concentrations of cellular adhesion molecules, which play a role in early atherogenesis. In comparison with PE, HELP LDL apheresis does not have major effects on essential plasma proteins and does not require replacement fluid, thus decreasing susceptibility to infections. One study noted that adverse events were documented in 2.9% of LDL apheresis treatments using the HELP system compared with 12% using PE. As per the manufacturer, patients must weigh at least 30kgs to be eligible for treatment with HELP. The H.E.L.P.® System (B.Braun Medizintechnologie GmbH, Germany) has been licensed by Health Canada since December 2000 as a Class 3 medical device (Licence # 26023) for performing LDL apheresis to acutely remove LDL from the plasma of 3 high-risk patient populations for whom diet has been ineffective and maximum drug therapy has either been ineffective or not tolerated. The 3 patient groups are as follows: Functional hypercholesterolemic homozygotes with LDL-C >500 mg/dL (>13mmol/L);Functional hypercholesterolemic heterozygotes with LDL-C >300 mg/dL (>7.8mmol/L);Functional hypercholesterolemic heterozygotes with LDL-C >200 mg/dL (>5.2mmol/L) and documented CADNo other LDL apheresis system is currently licensed in Canada. The Medical Advisory Secretariat systematically reviewed the literature to assess the effectiveness and safety of LDL apheresis performed with the HELP system for the treatment of patients with refractory HMZ and HTZ FH. A standard search methodology was used to retrieve international health technology assessments and English-language journal articles from selected databases. The GRADE approach was used to systematically and explicitly make judgments about the quality of evidence and strength of recommendations. The search identified 398 articles published from January 1, 1998 to May 30, 2007. Eight studies met the inclusion criteria. Five case series, 2 case series nested within comparative studies, and one retrospective review, were included in the analysis. A health technology assessment conducted by the Alberta Heritage Foundation for Medical Research, and a review by the United States Food and Drug Administration were also included. Large heterogeneity among the studies was observed. Studies varied in inclusion criteria, baseline patient characteristics and methodology. Overall, the mean acute relative decrease in LDL-C with HELP LDL apheresis ranged from 53 to 77%. The mean acute relative reductions ranged as follows: total cholesterol (TC) 47 to 64%, HDL-C +0. (ABSTRACT TRUNCATED)

Clinical features of familial hypercholesterolemia.

The clinical consequences of familial hypercholesterolemia (FH) result from its metabolic peculiarities that persist from very early childhood, leading to the accumulation of cholesterol in the form of xanthomas in skin and tendons and atheromatous lesions in the arterial wall, in particular, in the aorta and the stem of coronary arteries. Plasma cholesterol concentration markedly increases during the suckling period, soon attaining a level near 1000 mg/dl in homozygotes and 200 to 400 mg/dl in heterozygotes. By age 50, about 80% of FH males suffer from ischemic heart diseases, while only 20% to 30% of the females are moderately affected by coronary atherosclerosis. In addition to the low density lipoprotein (LDL) cholesterol level, higher triglyceride and lower high density lipoprotein (HDL) cholesterol levels correlate with an increased risk of ischemic heart diseases. A very important problem is that most of these patients do not feel themselves to be seriously ill until a severe myocardial infarction (often leading to sudden death) takes place during the third to fifth decades of life. Among the different types of receptor mutations, the incidence of ischemic heart diseases was much higher and more extensive among patients with the receptor-negative type than among those with the receptor-defective type with a residual receptor activity.

LDL receptor

Michael S. Brown and Joseph L. Goldstein were awarded the 1985 Nobel Prize in Physiology or Medicine for their identification of LDL-R and its relation to cholesterol metabolism and familial hypercholesterolemia. Disruption of LDL-R can lead to higher LDL-cholesterol as well as increasing the risk of related diseases. Individuals with disruptive mutations (defined as nonsense, splice site, or indel frameshift in LDLR have an average LDL-cholesterol of 279 mg dl−1, vs. 135 mg dl−1 for individuals with neither disruptive nor deleterious mutations. Disruptive mutations were 13-times more common in individuals with early-onset myocardial infarction or coronary artery disease than in individuals without either disease. Structure Gene

InternalMed_Harrison

LDL receptor allele. The population frequency of heterozy gous FH due to LDL receptor mutations was originally estimated to be 1 in 500 individuals, but recent data suggest it may be 2441 as high as approximately 1 in 250 individuals, making it one of the most common single-gene disorders in humans. FH has a higher prevalence in certain founder populations, such as South African Afrikaners, Christian Lebanese, and French Canadians. Heterozygous FH is characterized by elevated plasma levels of LDL-C (usually 200– 400 mg/dL) and normal levels of TGs. Patients with heterozygous FH have hypercholesterolemia from birth, and disease recognition is usually based on detection of hypercholesterolemia on routine screening, the appearance of tendon xanthomas, or the development of symptomatic cardiovascular disease. Inheritance is dominant, meaning that the condition was inherited from one parent and ~50% of the patient’s siblings can be expected to have hypercholesterolemia. The family history

Japanese Americans

Studies have shown that the CETP is linked to increased HDL levels. There is a very common pattern of two different cholesterol ester transfer protein gene mutations (D442G, 5.1%; intron 14G:A, 0.5%) found in about 3,469 Japanese American men. This was based on a program called the Honolulu Heart Program. The mutations correlated with decreased CETP levels (-35%) and increased HDL cholesterol levels (+10% for D442G). The relative risk of CHD was 1.43 in men with mutations (P<0.05), and after research found for CHD risk factors, the relative risk went up to 1.55 (P=0.02); after further adjustments for HDL levels, the relative risk went up again to 1.68 (P=0.008). Genetic CETP deficiency is an independent risk factor for coronary heart disease, which is due mainly to increased CHD risks in Japanese American men with the D442G mutation and lipoprotein cholesterol levels between 41 and 60 mg/dl. With research and investigations, the possibility of finding "bad genes" denounces the

Hypobetalipoproteinemia

Hypobetalipoproteinemia is a disorder consisting of low levels of LDL cholesterol or apolipoprotein B, below the 5th percentile. The patient can have hypobetalipoproteinemia and simultaneously have high levels of HDL cholesterol. Notably, in people who do not have the genetic disorder hypobetalipoproteinemia, a very low cholesterol level (less than 100mg/dl) may be a marker for poor nutrition, wasting disease, cancer, hyperthyroidism, and liver disease. In 1997 a study showed that Japanese Centenarians had ten fold increase of hypobetalipoproteinemia compared with controls. Causes One form is thought to be caused by mutated apolipoprotein B. Another form is associated with microsomal triglyceride transfer protein which causes abetalipoproteinemia. A third form, chylomicron retention disease (CRD), is associated with SARA2. Diagnosis Typically in hypobetalipoproteinemia, plasma cholesterol levels will be around 80–120 mg/dL, LDL cholesterol will be around 50–80 mg/dL.

[Incidence of familial defective apolipoprotein B-100 in cases of patients diagnosed with familial hypercholesterolemia].

Familial Hypercholesterolemia (FH) and Familial Defective Apolipoprotein B-100 (FDB) are monogenic, autosome, dominantly inherited diseases appearing as type II/a primary hypercholesterolemia. The frequency of the heterozygositic forms is 1:700-1:500 in European population. Both forms of hypercholesterolemia causes early onset coronary heart diseases (CHD). According to the recommendations of the international MED-PED program (Make Early Diagnoses--Prevent Early Death), we found 73 FH cases and their 377 first relatives (parents, siblings, children) were also assessed. 156 patients were diagnosed clinically FH (131 alive and 25 deceased), and 31.8% of the males and 32.4% of females suffered from early onset CHD. One family with FH consists of 5.46 members on the average and there are 2.39 FH patients in one family. In our FH cohort four patients with FDB (R3500Q mutation) were diagnosed with allelspecific PCR, and the mutation was detectable also in 9 cases out of 11 living family members. The plasma total cholesterol level of the FDB patients--especially at younger age--was very close to the normal values, which is in contrast to the findings in FH patients. Nevertheless, FDB can be one of the independent causes of the early onset CHD. Therefore, in families with high frequency of cardiovascular diseases the R3500Q mutation has to be considered.

Epidemiology of metabolic syndrome

Of the components of the cardiometabolic syndrome, only the prevalence of dyslipidemia has declined in the United States. Between 1999 and 2010, the percentage of U.S. adults with high total cholesterol declined from approximately 18% to 13%. However, according to the American Heart Association, nearly half of U.S. adults today (44%) are still at increased risk for atherosclerotic disease because their levels of total cholesterol are elevated (200 mg/dL or higher). Of these 98.8 million individuals with elevated cholesterol, 33.6 million have high cholesterol (240 mg/dL or above), and 71.3 million have low-density lipoprotein (LDL) cholesterol levels of 130 mg/dL or higher. In addition, approximately 19% of U.S. adults have low levels of high-density lipoprotein (HDL) cholesterol, and one-third have elevated triglycerides. Finally, dyslipidemia affects the vast majority (up to 97%) of individuals with diabetes and contributes to their elevated risk for cardiovascular disease.

Cholesterol

More current testing methods determine LDL ("bad") and HDL ("good") cholesterol separately, allowing cholesterol analysis to be more nuanced. The desirable LDL level is considered to be less than 100 mg/dL (2.6 mmol/L), although a newer upper limit of 70 mg/dL (1.8 mmol/L) can be considered in higher-risk individuals based on some of the above-mentioned trials. A ratio of total cholesterol to HDL—another useful measure—of far less than 5:1 is thought to be healthier. Total cholesterol is defined as the sum of HDL, LDL, and VLDL. Usually, only the total, HDL, and triglycerides are measured. For cost reasons, the VLDL is usually estimated as one-fifth of the triglycerides and the LDL is estimated using the Friedewald formula (or a variant): estimated LDL = [total cholesterol] − [total HDL] − [estimated VLDL]. Direct LDL measures are used when triglycerides exceed 400 mg/dL. The estimated VLDL and LDL have more error when triglycerides are above 400 mg/dL.

Documented need for more effective diagnosis and treatment of familial hypercholesterolemia according to data from 502 heterozygotes in Utah.

A project to help Utah residents with heterozygous familial hypercholesterolemia (FH) identified affected individuals by collecting detailed questionnaires from: (1) very high-risk persons in computer files of screening data (very high cholesterol levels, very early coronary artery disease, and strong positive family history); (2) confirmed FH index cases from a university lipid clinic; and (3) relatives of any confirmed FH cases. Questionnaires were received from 2,143 persons identifying 101 living index cases and 502 relatives meeting the criteria for the diagnosis of FH. Finding new FH heterozygotes was about one fourth as expensive by tracing relatives of confirmed FH cases by evaluating very high-risk persons. Of those meeting criteria for the diagnosis of heterozygous FH, only 31% reported being told by their physicians that they had FH, only 42% indicated that they were taking a cholesterol-lowering prescription medication, and only 23% had reasonably controlled cholesterol levels (below the 90th percentile). However, the data also suggest that good control is achievable in motivated patients. Among 106 FH heterozygotes who were early responders to a second follow-up questionnaire, 79% were taking prescription medications, of whom 49% had achieved cholesterol levels below the 90th percentile, and 17% even achieved cholesterol levels below the 50th percentile. We conclude that most patients with heterozygous FH are not diagnosed and not adequately treated. We demonstrated how many of these persons needing help could be identified efficiently by tracing relatives of known index cases.

Familial hypercholesterolemia: developments in diagnosis and treatment.

Familial hypercholesterolemia (FH) is a congenital disorder of lipid metabolism characterized by a marked elevation of the plasma concentration of LDL (low-density lipoprotein) cholesterol beginning in childhood and by the early onset of coronary heart disease. It is among the commonest genetic disorders, with an estimated prevalence in Germany of at least 1 per 500 persons. Review of pertinent literature retrieved by a selective search. FH is underdiagnosed and undertreated in Germany. It is clinically diagnosed on the basis of an elevated LDL cholesterol concentration (>190 mg/dL [4.9 mmol/L]), a family history of hypercholesterolemia, and early coronary heart disease, or the demonstration of xanthomas. The gold standard of diagnosis is the identification of the underlying genetic defect, which is possible in 80% of cases and enables the identification of affected relatives of the index patient. The recommended goals of treatment, based on the results of observational studies, are to lower the LDL cholesterol concentration by at least 50% or to less than 100 mg/dL (2.6 mmol/L) (for children: <135 mg/dL [3.5 mmol/L]). The target value is lower for patients with clinically overt atherosclerosis (<70 mg/dL [1.8 mmol/L]). Statins, combined with a health-promoting lifestyle, are the treatment of choice. Lipoprotein apheresis is used in very severe cases; its therapeutic effects on clinical endpoints and its side effect profile have not yet been documented in randomized controlled trials. Familial hypercholesterolemia is a common disease that can be diagnosed simply and reliably on clinical grounds and by molecular genetic testing. Timely diagnosis and appropriate treatment can lower the risk of atherosclerosis in heterozygous patients to that of the general population.

[Prevention of coronary heart disease in familial hypercholesterolemia].

Familial forms of isolated hypercholesterolemia are inherited autosomal-dominantly and are caused by defects of the low-density lipoprotein (LDL) receptor protein or its ligand, the apolipoprotein B-100, the exclusive apolipoprotein moiety of the LDL particles. Mutations at the LDL receptor gene locus (more than 150 different mutations have been described up to now) lead to familial hypercholesterolemia (FH); the only mutation at the apolipoprotein B-100 gene locus described in detail so far leads to the so-called familial defective apolipoprotein B-100 (FDB). Both lipid disorders are characterized by an increased risk for premature atherosclerosis involving primarily the coronary arteries. An increased risk for coronary heart disease can be expressed statistically by the excess mortality. In particular, individuals between the age of 20 and 59 are affected by an excess mortality; coronary deaths are approximately 100 times more frequent in patients between 20 and 39 with familial forms of hypercholesterolemia than within the normal population. On the other hand, in patients with myocardial infarctions before the age of 60, the diagnosis of FH is approximately 20 to 30 times more frequent than within the normal population. A regression of cardiovascular lesions subsequent to an intensive lipid-lowering therapy has clearly been demonstrated in patients with familial forms of hypercholesterolemia. Because of the serious prognosis of untreated familial forms of isolated hypercholesterolemia with respect to longevity, it is important to identify patients and their relatives with FH and FDB as early as possible and to treat them, besides a lipid-lowering diet, intensively with lipid-lowering drugs.

Cholesterol

The 1987 report of National Cholesterol Education Program, Adult Treatment Panels suggests the total blood cholesterol level should be: < 200 mg/dL normal blood cholesterol, 200–239 mg/dL borderline-high, > 240 mg/dL high cholesterol. The American Heart Association provides a similar set of guidelines for total (fasting) blood cholesterol levels and risk for heart disease: Statins are effective in lowering LDL cholesterol and widely used for primary prevention in people at high risk of cardiovascular disease, as well as in secondary prevention for those who have developed cardiovascular disease.

[Early diagnosis of familial hypercholesterolemia in Czech Republic in pursuance of MedPed Project].

Recent studies have revealed the prevalence of familial hypercholesterolemia (FH) is approximately twice higher than previously estimated and, thus, the disease affects one in 250 persons from the general population. Therefore FH remains the most frequent inherited metabolic disorder. Due to the genetic defect LDL-cholesterol accumulates both in the plasma and tissues leading to premature and accelerated atherosclerosis. Untreated patients with FH might suffer from myocardial infarction in the third or fourth decade, one third of these events being fatal. The disease is under-diagnosed and undertreated worldwide. In the Czech Republic the MedPed project focused on early diagnosis and initiation of proper treatment of FH aiming at lowering of the above mentioned risks was initiated in 1998. A crucial part of the project is so called cascade screening among the relatives of identified FH probands. There are 6,350 registered FH subjects in the nationwide registry, which represents 16% of the expected number of FH patients in the Czech Republic. This result of screening efforts ranks among the top countries in the world, however, also in spite of the recent expansion of FH treatment options early detection and initiation of treatment of FH remains in the centre of our attention.

Omega-3 fatty acid

Omega−3 fatty acids reduce blood triglyceride levels but do not significantly change the level of LDL cholesterol or HDL cholesterol in the blood. The American Heart Association position (2011) is that borderline elevated triglycerides, defined as 150–199 mg/dL, can be lowered by 0.5–1.0 grams of EPA and DHA per day; high triglycerides 200–499 mg/dL benefit from 1–2 g/day; and >500 mg/dL be treated under a physician's supervision with 2–4 g/day using a prescription product. In this population omega−3 fatty acid supplementation decreases the risk of heart disease by about 25%.

Cholesterol Levels in Genetically Determined Familial Hypercholesterolaemia in Russian Karelia.

Familial hypercholesterolaemia (FH) is a rare disease that tends to be diagnosed lately. In Russia, the genetic and phenotypic characteristics of the disease are not well defined. We investigated 102 patients with definite FH. In 52 of these patients (50.9%) genetic analysis was performed, revealing pathogenic mutations of the low density lipoprotein (LDL) receptor gene in 22 patients. We report here five mutations of the LDL receptor gene found in the Karelian FH sample for the first time. The detection rate of mutations in definite FH patients was 42.3%. Two groups of patients with a definite diagnosis of FH according to the Dutch Lipid Clinic Network criteria were compared: the first group had putatively functionally important LDL receptor gene mutations, while in the second group LDL receptor gene mutations were excluded by single-strand conformation polymorphism analysis. Total and LDL cholesterol levels were higher in the group with LDL receptor mutations compared to the mutation-free population. The frequency of mutations in patients with LDL cholesterol > 6.5 mmol/L was more than 3 times higher than that in patients with LDL < 6.5 mmol/L. Total and LDL cholesterol levels and the frequency of coronary heart disease and myocardial infarction were higher in the group with definite FH compared to groups with probable and possible FH. Cholesterol figures in FH patients of different age and sex from the Karelian population were comparable.

Familial hypercholesterolemia

Lipid measurements Cholesterol levels may be determined as part of health screening for health insurance or occupational health, when the external physical signs such as xanthelasma, xanthoma, arcus are noticed, symptoms of cardiovascular disease develop, or a family member has been found to have FH. A pattern compatible with hyperlipoproteinemia type IIa on the Fredrickson classification is typically found: raised level of total cholesterol, markedly raised level of low-density lipoprotein (LDL), normal level of high-density lipoprotein (HDL), and normal level of triglycerides. Total cholesterol levels of 350–550 mg/dL are typical of heterozygous FH while total cholesterol levels of 650–1000 mg/dL are typical of homozygous FH. The LDL is typically above the 75th percentile, that is, 75% of the healthy population would have a lower LDL level. Cholesterol levels can be drastically higher in people with FH who are also obese.

[Familial hypercholesterolemia - do we think enough about this severe disease?].

Familial hypercholesterolemia is the most common genetic metabolic disorder and is associated with significant morbidity and mortality from cardiovascular disease, in particular coronary heart disease (CHD). Gene mutations for LDL receptor, APOB or PCSK9 are the main causes of the disease. The incidence of homozygous form of disease is 1:1000000 and ofheterozygous 1:500. Some of the patients have clinical signs like xanthomas, xanthelasmas and corneal arcus. More predictive for the diagnosis are elevated serum LDL cholesterol values and positive family history of early CHD. Identification of the causative mutation provides definitive diagnosis. Diet, statins, combined therapy (statins and ezetimibe) are the first line of treatment, mostly in high doses. LDL apheresis is the procedure of mechanical removal of LDL particles from plasma and has to be performed in patients with homozygous or severe heterozygous form of the disease together with drug treatment. There is a need to increase the awareness of this disease in Croatia but also worldwide with one main goal: to early diagnose and prevent cardiovascular morbidity and mortality.

Statin

Secondary prevention Statins are effective in decreasing mortality in people with pre-existing cardiovascular disease. Pre-existing disease can have many manifestations. Defining illnesses include a prior heart attack, stroke, stable or unstable angina, aortic aneurysm, or other arterial ischemic disease, in the presence of atherosclerosis. They are also advocated for use in people at high risk of developing coronary heart disease. On average, statins can lower LDL cholesterol by 1.8 mmol/L (70 mg/dL), which translates into an estimated 60% decrease in the number of cardiac events (heart attack, sudden cardiac death) and a 17% reduced risk of stroke after long-term treatment. A greater benefit is observed with high-intensity statin therapy. They have less effect than the fibrates or niacin in reducing triglycerides and raising HDL-cholesterol ("good cholesterol").

Development of coronary heart disease in familial hypercholesterolemia.

We studied the development of coronary artery disease in 10 homozygous and 692 heterozygous patients with familial hypercholesterolemia. Seventy-five (22%) male heterozygotes and 35 (10%) female heterozygotes were affected by myocardial infarction, which was first noted in men in the 3rd decade of life and in women in the 4th decade of life. Thirty-eight (70%) out of the deceased 54 heterozygous patients died of coronary heart disease. The mean age at death was significantly less in male heterozygotes (54 years) than in female heterozygotes (69 years). Five homozygous and 105 male and 56 female heterozygous patients received coronary angiographic evaluation. The regression equations between age (X) and coronary stenosis index (Y) obtained by assigning score (0 to 5) to each of 15 coronary artery segments were Y = 1.57X - 20.43 (r = 0.956, p less than 0.05) in the homozygotes, Y = 0.52X - 9.11 (r = 0.438, p less than 0.001) in the male heterozygotes, and Y = 0.47X - 12.54 (r = 0.343, p less than 0.01) in the female heterozygotes. From these data, we can assume that coronary artery stenosis detectable by angiography will occur after 17 and 25 years of age in male and female heterozygotes, respectively, and the treatment of heterozygotes with lipid-lowering drugs can be delayed until late adolescence.

Antisense RNA

Another example of using an asRNA as a therapeutic agent is mipomersen, which was approved by FDA in 2013. Mipomersen was developed to manage the level of low-density lipoprotein cholesterol (LDL) in patients with homozygous familial hypercholesterolemia (HoFH), which is a rare autosomal dominant genetic condition. Because of the high level of total cholesterol (650–1000 mg/dL) and LDL receptor (above 600 mg/dL) in HoFH, patients with HoFH has a high risk for coronary heart disease. Because the protein apo-B-100 has been found to be required to produce very low-density lipoprotein (VLDL) and LDL, mipomersen complements with the mRNA of apo-B-100 and target it for RNAse H dependent degradation. Ultimately, mipomersen is able to reduce the level of LDL.

Did grandma give you heart disease? The new battle against coronary artery disease.

Atherosclerosis/coronary artery disease (CAD) is largely a result of genetically linked dyslipidemias that can often be identified in clinical practice. Expression of these genetic traits is highly individual and can be affected by environmental factors such as diet and exercise. By understanding the heterogeneity of CAD, it becomes clear that all patients cannot be optimally managed with the same therapeutic regimen. Whereas elevated low-density lipoprotein (LDL) cholesterol is strongly correlated with CAD risk, reduction of LDL cholesterol alone is not an adequate strategy in many cases. Patients with the small, dense LDL of the atherogenic lipoprotein profile (pattern B) experience a 3-fold increased risk of CAD, and pattern B is also correlated with the development of type 2 diabetes. Likewise, elevated lipoprotein(a) increases atherosclerotic risk, particularly in the presence of other risk factors, and is predictive of CAD risk in both women and men. Recent data show that the routine lipid profile--total cholesterol, triglycerides, LDL cholesterol, and high-density lipoprotein (HDL) cholesterol--does not detect the most common inherited dyslipidemias. Newer, more sophisticated tests, such as gradient gel electrophoresis, can detect disease-relevant lipidemic details, e.g., LDL subclass pattern, LDL particle diameter, and LDL subregions. Although these testing procedures are more expensive, their cost must be weighed against the potential lifelong cost of sometimes expensive drug treatment that may be avoided based on the results of such tests. Thus, by attending to the implications of family history, the interactions of genetic, metabolic, and environmental factors, and utilizing more targeted testing procedures, physicians can match the patient's disorder with specifically effective therapy while maintaining a cost-effective approach to disease management.

Hypolipoproteinemia

Hypolipoproteinemia, hypolipidemia, or hypolipidaemia (British English) is a form of dyslipidemia that is defined by abnormally lowered levels of any or all lipids and/or lipoproteins in the blood. It occurs through genetic disease (namely, hypoalphalipoproteinemia and hypobetalipoproteinemia), malnutrition, malabsorption, wasting disease, cancer, hyperthyroidism, and liver disease. Causes Causes of hypolipidemia include: Hypobetalipoproteinemia (low levels of LDL cholesterol or apolipoprotein B) Malnutrition Malabsorption Wasting disease Certain cancers Hyperthyroidism (an overactive thyroid) Liver disease Diagnosis It can be diagnosed via blood study that identifies fat particles. The patient must fast overnight to prevent interference from fat in the blood due to food intake. The criteria for this (without the involvement of cholesterol-lowering drugs) are total cholesterol levels below 120 mg/dL and LDL cholesterol levels under 50 mg/dL.

[A family-based strategy for diagnosing familial hypercholesterolemia].

Patients with familial hypercholesterolaemia have increased risk of developing coronary heart disease. The most cost-effective way of diagnosing patients with familial hypercholesterolaemia is to perform genetic testing of close relatives of already diagnosed patients. Probands with familial hypercholesterolaemia in whom the underlying mutation in the low-density lipoprotein receptor gene has been identified were informed that close relatives should also be tested. Blood samples were taken for molecular genetic testing from 851 first-degree relatives of patients with familial hypercholesterolaemia; 47.8 % tested positively and 52.2 % negatively. Among those with positive tests, only 41.5 % were on lipid-lowering drugs and only 6.1 % had a value for total serum cholesterol < 5 mmol/l. Six months after testing, 81.9 % were on lipid-lowering drugs, at which time a mean reduction in total serum cholesterol of 21.2 % (p < 0.0001) was observed in patients aged 18 and above who were not on treatment at the time of testing. Molecular genetic testing for familial hypercholesterolaemia in a family-based strategy is a cost-effective way of diagnosing patients with this condition that leads to implementation of effective preventive measures.

Lecithin cholesterol acyltransferase deficiency

Fish-eye Disease Lab Findings CBC: no anemia Urinalysis: no protein in the urine Blood Chemistries: normal blood urea nitrogen (BUN) and creatinine (no signs of kidney failure) Lipid Panel: low high-density lipoprotein (HDL) < 10 mg/dL, elevated very low-density lipoprotein (VLDL) and triglycerides, high plasma unesterified cholesterol in HDL particles, and low cholesterol ester in HDL particles but normal levels in low-density lipoprotein (LDL) and VLDL particles Plasma LCAT activity: decreased only in HDL particles but not LDL Genetic Findings in Fish-eye Disease Mutations in the LCAT gene, which is localized in the q21–22 region of chromosome 16, cause fish-eye disease. The mutation in the LCAT gene is homozygous for a Thr123→Ile mutation or Pro10→Leu mutation. New mutations have been identified as homozygosity for an A2205→G nucleotide substitution in exon 4 of the LCAT gene which is predicted to be the cause of an Asp131→Asn substitution.

Prevalence of familial hypercholesterolemia among young north Karelian patients with coronary heart disease: a study based on diagnosis by polymerase chain reaction.

Two deletions of the low density lipoprotein (LDL) receptor gene account for about 90% of the mutations that cause familial hypercholesterolemia (FH) in eastern Finland. The FH-Helsinki mutation deletes exons 16, 17 and a portion of exon 18, while the FH-North Karelia allele is characterized by a deletion of seven nucleotides from exon 6 of the LDL receptor gene. We developed a DNA assay based on the use of polymerase chain reaction (PCR) which simultaneously detects both of these mutations. We have screened 90 young (< 45 years) eastern Finns with symptomatic coronary heart disease (CHD) for the presence of these FH genes. One or the other of the mutations was present in 4 out of 55 survivors of acute myocardial infarction (AMI) and 4 out of 35 patients with angina pectoris (AP), but in none of 50 healthy controls of similar age. These data show a relatively high prevalence of confirmed FH in young CHD patients (AMI and MI combined: 8/90, or 9%), and also demonstrate the feasibility of PCR techniques in diagnosis of FH among populations with enrichment of specific types of LDL receptor gene mutations.

Suboptimal health

Another criterion for diagnosis of subhealth was defined as the presence of ≥ 1 of the following abnormalities: body mass index ≥ 25 kg/m2 or waist circumference ≥ 102 cm in men and 88 cm in women; systolic pressure 120-139 mmHg and/or diastolic pressure 80-89 mmHg; serum triglyceride level ≥ 150 mg/dL and/or total cholesterol level ≥ 200 mg/dL and/or high-density lipoprotein cholesterol level < 40 mg/dL in men and 50 mg/dL in women; serum glucose level 110–125 mg/dL; estimated glomerular filtration rate 60-89 ml/min/1.73 m2; levels of liver enzymes in liver function tests between 41-59 U/L, or with fatty liver disease but < 33% of affected hepatocytes; levels of oxidative stress biomarkers beyond the reference range of 95%; or problems with both sleep quality and psychological state. Population Health Status

Evidence that men with familial hypercholesterolemia can avoid early coronary death. An analysis of 77 gene carriers in four Utah pedigrees.

To study the genetic influence on serum cholesterol levels and early coronary heart disease, 1,134 individuals were screened from 18 Utah pedigrees. In most pedigrees, serum cholesterol appeared to be a purely polygenic trait, with 54% heritability. In four pedigrees with dominant familial hypercholesterolemia, male heterozygotes had a mean serum cholesterol level of 352 mg/dL, myocardial infarction at an average age of 42 years, and coronary death at an average age of 45 years. An informative pedigree structure allowed the identification of four ancestral males born before 1880 who carried this lethal gene and survived to ages 62, 68, 72, and 81 years. This suggests that some healthy life-style factors protected these men against the expression of a gene that has led to coronary disease by age 45 years in all of their heterozygous great-grandsons. One heterozygote showed a drop in serum cholesterol level from 426 to 248 mg/dL, with strict adherence to a low-fat diet without drugs. These observations should help encourage physicians to try harder to identify and help such individuals.

Low-density lipoprotein

where H is HDL cholesterol, L is LDL cholesterol, C is total cholesterol, T are triglycerides, and k is 0.20 if the quantities are measured in mg/dl and 0.45 if in mmol/l. There are limitations to this method, most notably that samples must be obtained after a 12 to 14 h fast and that LDL-C cannot be calculated if plasma triglyceride is >4.52 mmol/L (400 mg/dL). Even at triglyceride levels 2.5 to 4.5 mmol/L, this formula is considered inaccurate. If both total cholesterol and triglyceride levels are elevated then a modified formula, with quantities in mg/dl, may be used This formula provides an approximation with fair accuracy for most people, assuming the blood was drawn after fasting for about 14 hours or longer, but does not reveal the actual LDL particle concentration because the percentage of fat molecules within the LDL particles which are cholesterol varies, as much as 8:1 variation.

Cardiovascular features of homozygous familial hypercholesterolemia: analysis of 16 patients.

Familial hypercholesterolemia (FH) is characterized by an autosomal codominant inheritance, an abnormality in low-density lipoprotein (LDL) receptor function, elevated plasma cholesterol levels and premature atherosclerosis. Sixteen patients with homozygous FH were studied to correlate the extent of their atherosclerotic disease with their lipid levels and receptor function. The age range at initial presentation was 3 to 38 years (mean 12), and at the last examination, 6 to 43 years (mean 20). The mean pretreatment total plasma cholesterol concentration for all patients was 729 +/- 58 mg/dl (+/- standard error of the mean), and the mean LDL cholesterol level was 672 +/- 58 mg/dl (normal 60 to 176). High-density lipoprotein cholesterol was 28 +/- 3 mg/dl (normal 30 to 74). In the 7 patients with FH who had symptoms of myocardial ischemia (Group I), the mean pretreatment LDL cholesterol value (817 +/- 62 mg/dl) was higher than that of the 9 asymptomatic patients (Group II) (560 +/- 74 mg/dl). In Group I, 5 of 7 patients had left or right coronary ostial narrowing and 3 had significant left ventricular outflow obstruction. Most coronary arterial narrowing occurred in the right coronary and left anterior descending arteries and the least amount in the left circumflex coronary artery. A femoral bruit was the physical finding that correlated best with the Group I population; brother:sister pairs revealed a milder clinical course for the female. Seven of the 16 patients have survived into their third decade without symptoms. Comparison of these persons with those in whom angina developed reveals a marked heterogeneity in their clinical course, which appears to be associated with receptor negative/defective status.

Hyperlipidemia

Total cholesterol The combined quantity of LDL and HDL. A total cholesterol of higher than 240mg/dL is abnormal, but medical intervention is determined by the breakdown of LDL and HDL levels. LDL cholesterol LDL, commonly known as "bad cholesterol", is associated with increased risk of cardiovascular disease. LDL cholesterol transports cholesterol particles throughout your body, and can build up in the walls of the arteries, making them hard and narrow. LDL cholesterol is produced naturally by the body, but eating a diet high in saturated fat, trans fats, and cholesterol can increase your LDL levels. Elevated LDL levels are associated with diabetes, hypertension, hypertriglyceridemia, and atherosclerosis. In a fasting lipid panel, a LDL greater than 160 mg/dL is abnormal. HDL Cholesterol