Sleep restriction for 1 week reduces insulin sensitivity in healthy men.
OBJECTIVE
Short sleep duration is associated with impaired glucose tolerance and an increased risk of diabetes. The effects of sleep restriction on insulin sensitivity have not been established. This study tests the hypothesis that decreasing nighttime sleep duration reduces insulin sensitivity and assesses the effects of a drug, modafinil, that increases alertness during wakefulness.


METHODS
This 12-day inpatient General Clinical Research Center study included 20 healthy men (age 20-35 years and BMI 20-30 kg/m(2)). Subjects spent 10 h/night in bed for >or=8 nights including three inpatient nights (sleep-replete condition), followed by 5 h/night in bed for 7 nights (sleep-restricted condition). Subjects received 300 mg/day modafinil or placebo during sleep restriction. Diet and activity were controlled. On the last 2 days of each condition, we assessed glucose metabolism by intravenous glucose tolerance test (IVGTT) and euglycemic-hyperinsulinemic clamp. Salivary cortisol, 24-h urinary catecholamines, and neurobehavioral performance were measured.


RESULTS
IVGTT-derived insulin sensitivity was reduced by (means +/- SD) 20 +/- 24% after sleep restriction (P = 0.001), without significant alterations in the insulin secretory response. Similarly, insulin sensitivity assessed by clamp was reduced by 11 +/- 5.5% (P < 0.04) after sleep restriction. Glucose tolerance and the disposition index were reduced by sleep restriction. These outcomes were not affected by modafinil treatment. Changes in insulin sensitivity did not correlate with changes in salivary cortisol (increase of 51 +/- 8% with sleep restriction, P < 0.02), urinary catecholamines, or slow wave sleep.


CONCLUSIONS
Sleep restriction (5 h/night) for 1 week significantly reduces insulin sensitivity, raising concerns about effects of chronic insufficient sleep on disease processes associated with insulin resistance.
Buxton
Orfeu M
OM
Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, USA. orfeu_buxton@hms.harvard.edu
Pavlova
Milena
M
Reid
Emily W
EW
Wang
Wei
W
Simonson
Donald C
DC
Adler
Gail K
GK
D000328:Adult; D001288:Attention / Q000502:physiology; D001481:Basal Metabolism; D001559:Benzhydryl Compounds / Q000494:pharmacology*; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism; D002153:Calorimetry, Indirect; D000697:Central Nervous System Stimulants / Q000494:pharmacology; D004311:Double-Blind Method; D015309:Glucose Clamp Technique; D005951:Glucose Tolerance Test; D006801:Humans; D006946:Hyperinsulinism / Q000097:blood; D007328:Insulin / Q000494:pharmacology*; D008297:Male; D000077408:Modafinil; D018579:Patient Selection; D012016:Reference Values; D012892:Sleep Deprivation / Q000503:physiopathology*; D014851:Wakefulness / Q000502:physiology; D055815:Young Adult
D001559:Benzhydryl Compounds; D001786:Blood Glucose; D000697:Central Nervous System Stimulants; D007328:Insulin; D000077408:Modafinil