Purpose: Sleep duration has emerged as a crucial factor affecting body weight and feeding behaviour. The aim of our study was to explore the relationship among sleep duration, body composition, dietary intake, and quality of life (QoL) in obese subjects.
Methods: Body composition was assessed by DXA. "Sensewear Armband" was used to evaluate sleep duration. SF-36 questionnaire was used to evaluate quality of life (QoL). A 3-day dietary record was administered. Subjects were divided into 2 groups: sleep duration > and ≤300 min/day.
Results: 137 subjects (105 women and 32 men), age: 49.8 ± 12.4 years, BMI: 38.6 ± 6.7 kg/m(2), were enrolled. Sleep duration was ≤300 min in 30.6 % of subjects. Absolute and relative fat mass (FM) (40.5 ± 9 vs. 36.5 ± 9.1 kg; 40.2 ± 4.7 vs. 36.9 ± 5.6 %), and truncal fat mass (19.2 ± 6.1 vs. 16.6 ± 5 kg; 38.6 ± 5.3 vs. 35.2 ± 5.5 %) were higher in subjects sleeping ≤300 min when compared to their counterparts (all p < 0.05), whereas just a tendency towards a higher BMI was observed (p = 0.077). Even though energy intake was not different between groups, subjects sleeping ≤300 min reported a higher carbohydrate consumption per day (51.8 ± 5.1 vs. 48.4 ± 9.2 %, p = 0.038). SF-36 total score was lower in subjects sleeping ≤300 min (34.2 ± 17.8 vs. 41.4 ± 12.9, p = 0.025). Sleep duration was negatively associated with FM (r = -0.25, p = 0.01) and SF-36 total score (r = -0.31, p < 0.001). The inverse association between sleep duration and SF-36 total score was confirmed by the regression analysis after adjustment for BMI and fat mass (R = 0.43, R (2) = 0.19, p = 0.012).
Conclusion: Reduced sleep duration negatively influences body composition, macronutrient intake, and QoL in obese subjects.
Keywords: Body composition; Dietary intake; Obesity; Quality of life; Sleep.