Shift work sleep disorder

Shift work sleep disorder (SWSD) is a circadian rhythm sleep disorder characterized by insomnia, excessive sleepiness, or both affecting people whose work hours overlap with the typical sleep period. Insomnia can be the difficulty to fall asleep or to wake up before the individual has slept enough. About 20% of the working population participates in shift work. SWSD commonly goes undiagnosed, so it's estimated that 10–40% of shift workers have SWSD. The excessive sleepiness appears when the individual has to be productive, awake and alert. Both symptoms are predominant in SWSD. There are numerous shift work schedules, and they may be permanent, intermittent, or rotating; consequently, the manifestations of SWSD are quite variable. Most people with different schedules than the ordinary one (from 8 AM to 6 PM) might have these symptoms but the difference is that SWSD is continual, long-term, and starts to interfere with the individual's life. There have been many studies suggesting health risks associated with shift work. Many studies have associated sleep disorders with decreased bone mineral density (BMD) and risk for fracture. Researchers have found that those who work 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 shift workers. Obesity, diabetes, insulin resistance, elevated body fat levels and dyslipidemias were shown to be much higher in those who work night shift. SWSD can increase the risk of mental disorders. Specifically, depression, anxiety, and alcohol use disorder is increased in shift workers. 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 loss and decreased quality of sleep is another effect of shift work.