Whereas past studies have shown that sleep disorders are underdiagnosed and undertreated, new research is providing a better understanding of sleep disorders. New information on pharmacogenetics and neurobiomolecular mechanisms of sleep-wake cycles has emphasized the need for good sleep and its impact on quality of life.
Research has found that insomnia negatively affects physical health. There is an increased likelihood of having overall health complaints, increased health care use, and a more frequent need for hospitalization for individuals with chronic insomnia. Chronic pain and symptoms associated with fibromyalgia and other medical disorders also are possible effects in individuals with sleep disorders. In addition, sleep deprivation influences systolic and diastolic blood pressure in these patients, compared with patients who get 8 hours of sleep a night. There is an average difference in blood pressure of 3 mm Hg to 7 mm Hg within a matter of 5 to 7 days.
Moreover, studies have indicated a reduction in insulin sensitivity in patients with insomnia. Researchers have found that patients with chronic insomnia are susceptible to impaired glucose tolerance, an increased likelihood of having diabetes mellitus, and higher levels of cortisol in the evening.