Objective
Short sleep duration has been reported to be associated with obesity, type 2 diabetes, and pre-diabetes. Since excess weight, glucose abnor
malities, and insulin resistance tend to cluster, the individual role insulin resistance
may have in habitual shortened sleep is unclear. The study purpose was to assess whether habitual sleep curtail
ment is independently related to insulin resistance in obese individuals.
Materials/Methods
Non-diabetic, overweight/obese individuals from the community were stratified as insulin-resistant (n = 35) or insulin-sensitive (n = 21) based on steady-state plasma glucose concentrations (SSPG) during the insulin suppression test. Seventy-five gram oral glucose tolerance tests were performed. Participants were asked, 鈥淥n average, how many hours of sleep do you get per night?鈥?Shortened sleep duration was defined as less than 7 h of sleep per night.
Results
SSPG concentrations differed 2.5-fold (m>Pm> < 0.001) between insulin-resistant and insulin-sensitive individuals. Impaired fasting glucose and glucose intolerance were prevalent in both groups (> 40%); however, body mass index, waist circumference, mean fasting or 2-h post-glucola glucose concentrations were not significantly different. Insulin-resistant individuals reported (mean 卤 SD) fewer hours of sleep than did insulin-sensitive individuals (6.53 卤 1.1 vs 7.24 卤 0.9 h, m>Pm> < 0.05). Shortened sleep duration was more prevalent among insulin-resistant as compared with insulin-sensitive individuals (60% vs 24%, m>Pm> < 0.05).
Conclusions
Non-diabetic, insulin-resistant individuals averaged fewer hours of sleep and were more likely to report shortened sleep duration as compared with similarly obese insulin-sensitive individuals. There appears to be an independent association between habitual shortened sleep and insulin resistance among obese, dysglycemic adults without diabetes.