Physiologic Effects of Sleep Restriction

Not Applicable

Completed

Brief Summary: Evidence suggests a relationship between sleep deprivation and cardiovascular disease. The investigators wish to determine whether 9 nights of modest sleep restriction results in activation of cardiovascular disease mechanisms, thus potentially increasing the risk of cardiovascular disease. The investigators hypothesize that sleep restriction will result in elevated blood pressure, inflammation, and neurocognitive deficits.

Detailed Description: Evidence suggests a relationship between sleep deprivation and cardiovascular disease. Voluntary sleep restriction is common, with 28% of the US adult population reports getting 6 or fewer hours of sleep per night, and those who do are 24% more likely to have cardiovascular disease and have twice the risk of hypertension. Insufficient sleep may conceivably be one of the most common, and most preventable, cardiovascular risk factors. The investigators wish to determine whether 9 nights of modest sleep restriction results in activation of cardiovascular disease mechanisms, thus potentially increasing the risk of cardiovascular disease. The investigators will combine our cardiovascular studies with state-of-the art sleep monitoring and neurocognitive tests to provide unambiguous data on the physiologic effects of sleep restriction. Together, the investigators findings will help explain whether the reduced sleep duration in the general population may be contributing to the current epidemic of cardiovascular disease, and suggest strategies to reduce this risk.

Recruitment & Eligibility

Inclusion Criteria

Age 18-40 years
No chronic medical conditions other than seasonal or environmental allergies
On no prescription medications other than second generation antihistamines (Cetirizine, Fexofenadine, Desloratadine, Loratadine, etc), oral contraceptive pills, or intrauterine devices.
BMI 18.5-35 kg/m2
Both normotensive and prehypertensive people are eligible and will be studied
Not a current smoker or tobacco user
Not pregnant or breast feeding and not intending to become pregnant or breast feed

Exclusion Criteria

The investigators will exclude subjects who have any medical or psychiatric disorders
History of anxiety or depression, and those taking any medications other than non-sedating antihistamines or oral contraceptives.
Those found to have depression on a depression screening tool (BDI-II) will be excluded. Current smokers will be excluded.
All female subjects will undergoing a screening pregnancy test and excluded if positive.
Subjects found to have significant sleep disorders will be excluded.

Arm && Interventions

Group	Intervention	Description
sleep restriction	sleep restriction	restricted sleep during the experimental period

Primary Outcome Measures

Name	Time	Method
Change in blood pressure	throughout 16 days	Change in mean arterial blood pressure over 24 hours, measured during acclimation, experimental, and recovery timepoints over the study period.

Secondary Outcome Measures

Name	Time	Method
Change in electrocardiographic characteristics	throughout 16 days	Change in electrocardiographic characteristics, measured during acclimation, experimental, and recovery timepoints.
Change in fat tissue characteristics	throughout 16 days	Change in fat tissue characteristics, determined by analysis of a fat biopsy sample.
Change in catecholamines	throughout 16 days	Change in catecholamines, measured during acclimation, experimental, and recovery
Change in arterial stiffness	throughout 16 days	Change in arterial stiffness, measured during acclimation, experimental, and recovery timepoints.
Change in markers of inflammation	throughout 16 days	Change in markers of inflammation, measured during acclimation, experimental, and recovery timepoints.
Change in baroreflex sensitivity	throughout 16 days	Change in baroreflex sensitivity, measured during acclimation, experimental, and recovery
Change in endothelial function	throughout 16 days	Change in endothelial function, measured during acclimation, experimental, and recovery timepoints.