Sleep Disturbance, Changes in Energy Intake and Body Compositing During Weight Loss in the POUNDS LOST Trial

To examine associations between sleep disturbance and changes in weight and body composition, and the mediating role of changes of appetite and food cravings in the POUNDS Lost 2-year weight-loss diet intervention trial, this study included 810 overweight or obese individuals with baseline sleep disturbance assessment, who were randomly assigned one of four diets varying in macronutrient composition. Changes in body weight and fat distribution were assessed by dual x-ray absorptiometry (DXA) and computed tomography (CT) during the 2-year intervention. Participants were asked to provide sleep disturbance levels (no, slight, moderate, or great) at baseline and to recall their sleep disturbances since last visit at 6, 12, 18 and 24 months. Weight loss during the first 6 months was followed by 1.5 years of steady weight regain. Participants with greater sleep disturbance from baseline to 6 months showed significant losses of body weight (P trend < 0.001) and waist circumference (P trend = 0.002) at 6 months, after multivariate adjustment. Compared with individuals without sleep disturbance at all from baseline to 6 months, those with slight, moderate, or great sleep disturbance showed an elevated risk of failure to lose weight (–5% or more loss) at 6 months, when the maximum weight loss was achieved, with OR of 1.24 (95% CI 0.87, 1.78), 1.27 (95% CI 0.75, 2.13) or 3.12 (95% CI 1.61, 6.03), respectively. In addition, we observed that the repeatedly measured levels of sleep disturbance over 2 years were inversely associated with the overall weight loss rate (weight changes per 6 months) (P trend < 0.001). Further, sleep disturbances during weight loss from baseline to 6 months and weight regain from 6 months to 24 months were significantly predictive of total fat, total fat mass percent and trunk fat percent changes during the 2 years. Our results also indicated that food cravings for carbohydrates/starches, fast food fats, sweets; cravings, prospective consumption, hunger of appetite measurements; dietary restraint, disinhibition and hunger subscales measured at 6 months significantly mediated the effects of sleep disturbance on weight loss. Our results indicate that more severe sleep disturbance during weight loss is associated with an elevated risk of failure to lose weight during the dietary intervention. Food cravings and eating behaviors may partly mediate these associations.