Sleep
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Sleep and circadian rhythms are biologic processes operative in health and disease, but as yet there is no articulated curriculum for undergraduate medical education. ⋯ The core competencies can be designed to improve physician knowledge and skills in recognizing and intervening in sleep problems and disorders. Learning objectives can be immediately incorporated into most medical school curricula. At the same time, these competencies serve as an important bridge across multiple medical content areas and disciplines and between undergraduate and postgraduate training.
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Randomized Controlled Trial Clinical Trial
The cumulative cost of additional wakefulness: dose-response effects on neurobehavioral functions and sleep physiology from chronic sleep restriction and total sleep deprivation.
To inform the debate over whether human sleep can be chronically reduced without consequences, we conducted a dose-response chronic sleep restriction experiment in which waking neurobehavioral and sleep physiological functions were monitored and compared to those for total sleep deprivation. ⋯ Since chronic restriction of sleep to 6 h or less per night produced cognitive performance deficits equivalent to up to 2 nights of total sleep deprivation, it appears that even relatively moderate sleep restriction can seriously impair waking neurobehavioral functions in healthy adults. Sleepiness ratings suggest that subjects were largely unaware of these increasing cognitive deficits, which may explain why the impact of chronic sleep restriction on waking cognitive functions is often assumed to be benign. Physiological sleep responses to chronic restriction did not mirror waking neurobehavioral responses, but cumulative wakefulness in excess of a 15.84 h predicted performance lapses across all four experimental conditions. This suggests that sleep debt is perhaps best understood as resulting in additional wakefulness that has a neurobiological "cost" which accumulates over time.
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Fruit flies exhibit a sleep-like rest state that shares behavioral characteristics with mammalian sleep, including a homeostatic increase in rest after deprivation by mechanical methods. We tested the effect of modafinil, a novel wake-promoting agent, to discover whether its effect is conserved. Flies fed various concentrations of modafinil were compared to groups of control flies fed diluent only. ⋯ However, modafinil withdrawal combined with 6H total rest deprivation significantly enhanced the rebound, suggesting that a rest debt is accumulating during modafinil. We conclude that modafinil affects states of arousal in Drosophila in the same direction as it does in mammals. This discovery provides a tool for searching for conserved molecular mechanisms by which modafinil regulates rest and waking.
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Beginning with modest clinical observations in 1984, a picture has evolved suggesting that sympathetic nervous system over activity may be responsible in part for the elevated blood pressure seen in obstructive sleep apnea patients. Early studies of urinary and plasma catecholamines indirectly suggested sympathetic over activity carried to daytime, non-apneic conditions. Later intra-neuronal recordings of muscle sympathetic nerve activity directly demonstrated both acute and diumal (non-apneic) sympathetic over activity. ⋯ There is no marker for separating sleep apnea patients with hypertension derived solely from intermittent hypoxia from other secondary causes. Perhaps endothelial cell molecular markers could help to identify patients at risk for cardiovascular change associated with snoring and apnea, as well to guide treatment. Finally, studies demonstrating microvascular changes in blood vessels are extremely difficult to do, but promise to yield important knowledge about cellular mechanisms and results of long-term treatment of sleep apnea on cardiovascular disease.
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Randomized Controlled Trial Multicenter Study Clinical Trial
A 12-month, open-label, multicenter extension trial of orally administered sodium oxybate for the treatment of narcolepsy.
To evaluate the long-term safety and efficacy of nightly sodium oxybate for the treatment of narcolepsy. ⋯ Sodium oxybate is an effective and well-tolerated treatment for narcolepsy.