There have been many studies suggesting health risks associated with<unk> <unk> . Many studies have associated sleep disorders with decreased bone mineral density (BMD) and risk for fracture. Researchers have found that those who<unk>  long-term in night positions, like nurses, are at a great risk for wrist and hip fractures (RR=1.37). Low fertility and issues during pregnancy are increased in<unk> <unk> ers. Obesity, diabetes, insulin resistance, elevated body fat levels and dyslipidemias were shown to be much higher in those who<unk>  night<unk> . SWSD can increase the risk of mental disorders. Specifically, depression, anxiety, and alcohol use disorder is increased in<unk> <unk> ers. Because the circadian system regulates the rate of chemical substances in the body, when it is impaired, several consequences are possible. Acute sleep loss has been shown to increase the levels of t-tau in blood plasma, which may explain the neurocognitive effects of sleep loss. Sleep quality Sleep loss and decreased quality of sleep is another effect of<unk> <unk> . To promote a healthy lifestyle, the American Academy of Sleep Medicine recommended that an adult have 7 or more hours of sleep per day. Each year there are almost 100,000 deaths estimated in the U.S. because of medical errors. Sleep deprivation and sleep disorders are factors that contribute significantly to these errors. In the same article, the authors affirm that there is a high prevalence of sleepiness and symptoms of sleep disorders related to the circadian system in medical center nurses. In a study done with around 1100 nurses, almost half of them (49%) reported sleeping less than 7 hours per day, a significant increase compared to national figures, in which 28% of people claimed to sleep less than 7 hours per night. Having a lack of sleep can impact cognitive performance. For example, it might become difficult to stay focused and concentrate, and reaction times might also be slowed down. SWSD might interfere with making decisions quickly, driving, or flying safely. Sleep loss seen in<unk> <unk> ers greatly impairs cognitive performance, being awake for 24 hrs. straight results in a cognitive performance that is equal to a blood-alcohol of 0.10, which is over the legal limit in most states. All of these factors can affect<unk>  efficiency and cause accidents. Michael Lee et al. demonstrated that those<unk> ing night<unk> s had a significantly higher risk of hazardous driving events when compared to those on a typical day<unk>  schedule. Accidents in the<unk> place have been found to be 60% higher in<unk> <unk> ers. They can affect the individual's social life and cause a lack of well-being and happiness. Poor sleep quality has also been associated with decreased quality of life, based on a SF-36 assessment. Sleep and alertness Although SWD affects many<unk> <unk> ers, its manifestation is still unclear within the general<unk> -working population. A field study investigating the nature of SWD in an experimental (with SWD) and control (non-SWD) group of Finnish<unk> <unk> ers revealed decreased total sleep time (TST) and increased sleep deficit before morning<unk> s. Furthermore, the SWD group also exhibited decreased objective sleep efficiency, decrease in sleep compensation over the free days, increased sleep latency, and finally poorer sleep quality was recorded in the SWD group compared to the non-SWD group. Moreover,<unk> <unk> ers with SWD scored significantly higher on the Karolinska Sleepiness Scale (KSS) when assessed at the beginning and the end of morning<unk> s and at the end of night<unk> s, while having more attentional lapses at the beginning of night<unk> s. Many studies have shown evidence of how partial and total sleep deprivation affects<unk>  productivity, absenteeism, fatal<unk> place accidents, and more. In a study by Akkerstedt et al., those who had a hard time sleeping in the past two weeks were at a greater risk for having a fatal<unk> place accident (RR=1.89, 95% CI 1.22–2.94). Other sleep disorders, like OSA which are risk factors for SWSD, have also been associated with low productivity, absenteeism, and accidents. At a cognitive level, sleep deprivation has been shown to cause decreased attentiveness, increased micro-sleeps, delayed psychomotor response, performance deterioration, neglect of activities, decline in<unk> ing memory, and more. Immune functioning Partial and total sleep deprivation has been linked to an increase of pro-inflammatory markers, such as IL-6, and a decrease in anti-inflammatory markers, such as IL-10, that plays a role in tumor suppression. Chronic<unk> <unk>  has been associated with decreased immune function in nurses. In a study by Naigi, et. al., over the course of a<unk> , nurses exhibited decreasing levels of Natural Killer cells, an innate immune response that plays a role in infectious disease and tumor suppression. Other researchers have found that less sleep at night increased the risk of developing the common cold. A supporting study by Moher et al. showed that<unk> <unk> ers were more likely to develop infectious diseases after exposure compared to daytime<unk> ers. A poorly functioning immune system may leave<unk> ers vulnerable for developing occupational illnesses. Sleep loss is also associated with an increase in TNF, a marker of systemic immune functioning. Cardiovascular disease Decreased sleep quality and duration have also been associated with other chronic illnesses, such as cardiovascular disease. Many studies have shown that prolonged sleeplessness and sleep disorders, such as OSA, increases systemic levels of CRP, a marker of cardiovascular disease. Many studies have shown that lack of sleep causes blood pressure to increase from the prolonged stimulation of the nervous system. The increase of inflammatory markers, like IL-6, up-regulate the production of CRP. SWSD in firefighters SWSD can affect many occupations, but firefighters are at a greater risk because of their extended (24hr)<unk>  and frequent sleep interruptions due to emergencies. Many firefighters suffer from sleep disorders as a result of their extended<unk>  and frequently disrupted sleep. In a study on firefighters by Barger, et al., over a third of study participants screened positive for a sleep disorder, but most had not received a previous medical diagnosis for any sleep disorders. Those with sleep disorders were also at a higher risk for being in a motor vehicle crash (OR=2.0 95% CI 1.29–3.12, p=0.0021), near crash (OR=2.49 95% CI 2.13–2.91, p < 0.0001), and nodding off while driving (OR=2.41 95% CI 2.06–2.82, p < 0.0001).
Shift work sleep disorder
Circadian rhythm sleep disorder
Central sleep apnea
Sleep apnea
Sleep disorder
Sleep deprivation
Obstructive sleep apnea
Sleep-related breathing disorder