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Sleep Restriction and Immune Health

It has long been known that sleep is a truth teller of mood. The poorer the sleep quality, the poorer the emotional response. Every parent knows this with a child short on sleep. What are the cellular effects?

From an abstract looking at catch up sleep and human inflammation we find the following: "Despite its prevalence in modern society, little is known about the long-term impact of restricting sleep during the week and ‘catching up’ on weekends. This common sleep pattern was experimentally modeled with three weeks of 5 nights of sleep restricted to 4 h followed by two nights of 8-h recovery sleep. In an intra-individual design, 14 healthy adults completed both the sleep restriction and an 8-h control condition, and the subjective impact and the effects on physiological markers of stress (cortisol, the inflammatory marker IL-6, glucocorticoid receptor sensitivity) were assessed. Sleep restriction was not perceived to be subjectively stressful and some degree of resilience or resistance to the effects of sleep restriction was observed in subjective domains. In contrast, physiological stress response systems remain activated with repeated exposures to sleep restriction and limited recovery opportunity. Morning IL-6 expression in monocytes was significantly increased during week 2 and 3 of sleep restriction, and remained increased after recovery sleep in week 2 and week 3. Serum cortisol showed a significantly dysregulated 24 h-rhythm during weeks 1, 2, and 3 of sleep restriction, with elevated morning cortisol, and decreased cortisol in the second half of the night. Glucocorticoid sensitivity of monocytes was increased, rather than decreased, during the sleep restriction and sleep recovery portion of each week. These results suggest a disrupted interplay between the hypothalamic-pituitary-adrenal and inflammatory systems in the context of repeated exposure to sleep restriction and recovery. The observed dissociation between subjective and physiological responses may help explain why many individuals continue with the behavior pattern of restricting and recovering sleep over long time periods, despite a cumulative deleterious physiological effect." (Simpson N. et. al. 2016)

Ok! This is a fascinating study as the effects of the sleep deprivation persisted despite perceived recovery sleep. This is a very well done and eye opening study as the old adage that I will sleep on the weekend or when I have the time is a clear recipe for immunological decay over time. The steroid markers and immune markers of stress and inflammation remained wonky despite the catch up sleep. The other interesting finding is the reality that we habituate to the sleep deprivation. This is a classical conditioning to feeling ok despite not being so. This was my life for 7 years from medical school to residency. I shudder to think about my markers of inflammation during these years.

What about the effect of sleep deprivation on cardiac health?

From PLOSOne we see the following:"5 nights of sleep restriction increased lymphocyte activation and the production of proinflammatory cytokines including IL-1β IL-6 and IL-17; they remained elevated after 2 nights of recovery sleep, accompanied by increased heart rate and serum CRP, 2 important risk factors for cardiovascular diseases. Therefore, long-term sleep restriction may lead to persistent changes in the immune system and the increased production of IL-17 together with CRP may increase the risk of developing cardiovascular diseases." (van Leeuwen et. al. 2009)

There are so many antecedent risk factors for myocardial disease that are uncontrollable. Sleep is controllable. Sleep is turning out to be a major variable in the human response to many disease triggers , especially infection.

Think of these studies when you read the immunology of exercise and muscle cell hypertrophy below. The links are critical. Sleep deprivation will 100% impair muscle healing and workout recovery. If you are an athlete, sleep is your best friend.

Focus on a quality sleep time by going to bed at the same time most nights, by awakening at the same time most mornings, by reducing nighttime lights and screens that delay sleep onset, by avoiding late night meals, by exercising daily, by keeping the sleeping area dark, by avoiding caffeine and alcohol and more.

More coming on sleep in the coming weeks.

For sleep and klotho,

Dr. M

Simpson Brain Behav Immune

Van Leeuwen PlosOne

Communications Biology