Abstract 10098: Predictors of Sleep Quality Improvement Among Overweight or Obese Individuals: A Randomized Controlled Trial

Abstract

BACKGROUND: Sleep disturbances have adverse cardiovascular consequences and are linked to glucose intolerance and obesity. Weight loss and exercise are primary treatments for obese patients with glucose intolerance yet few lifestyle intervention trials have evaluated changes in sleep quality in relation to changes in body composition and fitness.

METHODS: We randomized persons aged 35-65 years with type 2 diabetes or pre-diabetes to 6-months of weight loss diet (D); or D combined with supervised moderate-intensity exercise training (D+E). Sleep quality was determined with a 50 item self-report questionnaire that identifies symptoms of apnea, daytime fatigue, hypersomnolence, circadian rhythm sleep disorder, insomnia, restless sleep, parasomnia, and dream disorders. Sleep quality is a composite score of all these items. Other measurements included weight; body mass index (BMI); total, abdominal subcutaneous and visceral fat by magnetic resonance imaging; and aerobic fitness expressed as VO₂peak during treadmill testing.

RESULTS: Of 77 subjects randomized, 55 participants (54.8 ± 7.8 years; n=24 of 38 D, n=31 of 39 D+E) completed the study. At 6 months, both groups improved from baseline (p<0.05 for all) but did not differ in their changes for body weight (D: -6.04 ± 4.54 kg; D+E: -6.68 ± 4.48 kg, p= 0.61), abdominal total fat (D: -101.93 ± 68.67 cm²; D+E:-104.16 ± 72.37 cm², p= 0.92), VO₂peak (D: 2.26 ± 3.92 ml/kg/min ; D+E:3.71 ±2.65 ml/kg/min, p=0.11), and sleep quality (D: -3.53 ± 7.69; D+E:-0.37 ±7.23, p=0.16). In bivariate analysis, improvement in sleep quality was associated with a reduction in BMI (r=0.47, p<0.01); abdominal subcutaneous (r=0.55, p<0.01) and abdominal total fat (r=0.47, p<0.01). In a multivariate analysis, adjusting for baseline sleep quality, a reduction in subcutaneous fat (beta=0.40, p <0.01) was the strongest predictor of improved sleep quality.

CONCLUSION: The novel finding herein is that a reduction in abdominal subcutaneous fat, with either diet alone or diet plus exercise, was associated with improved sleep quality. These data suggest that interventions that target central obesity may prove to be an effective strategy for reducing the incidence and severity of sleep disorders.