Chronobiology—the science of daily (circadian), monthly, tidal, and seasonal rhythms—has undergone exponential growth in the past decade, with major discoveries at the molecular and neuroanatomic level.
Results of an annual physical examination of a 54-year-old man have led you to suspect he may have—or be at high risk for—sleep apnea syndrome. His BMI is 37 and his blood pressure is 126/82 mm Hg. He has hypertension and hyperlipidemia.
You are performing an annual visit evaluation for a 54-year-old sales manager. He has a history of hypertension and hyperlipidemia, both managed. He has no major complaints. He reports restful sleep and no daytime sleepiness.
What is sleep normally and what are the primary factors that regulate sleep? Understanding that the primary factors that regulate the sleep wake cycle are homeostatic and circadian will help clinicians assess sleep problems in patients.