Table 1.
Summary of the recent epidemiological studies examining the association between sleep duration and obesity in adults
| Author | Description | Cohort | Sleep assessment | Results |
|---|---|---|---|---|
| Buxton and Marcelli [16] | Cross-sectional Data source: 2004–05 US National Health Interview Survey (US) |
56 507 M, F Age 18–85 years |
Self-reported sleep duration | <7 h 6% higher probability of obesity 7–8–h reference category >8 h 3% higher probability of obesity |
| Magee et al. [17] | Cross-sectional Data source: 45 and UP Study data (Australia) |
45 325 M, F Age 55–95 years |
Self-reported sleep duration | Age 55–64 years <6 h AOR obesity 1.52 (CI 1.21–1.89; P < 0.001) 6 h AOR obesity 1.42 (CI 1.26–1.61; P < 0.001) 7 h reference category ≥9 h AOR obesity 1.19 (CI 1.06–1.34; P < 0.001) Age >65: NS |
| Magee et al. [18] | Cross-sectional Data source: 45 and UP Study (Australia) |
16 951 M, F full-time workers Age 45–65 years |
Self-reported sleep duration | Inverse association between sleep duration and BMI (β = –0.615, P < 0.001) |
| Anic et al. [19] | Cross-sectional Data source: Collaborative Breast Cancer Study (US) |
5549 F Age 20–75 years |
Self-reported sleep duration | <6 h AOR of obesity 1.89 (CI 1.45–2.47; P < 0.0001); AOR extreme obesity 3.12 (CI 1.70–5.75; P = 0.0003) 6–6.9 h AOR obesity 1.52 (CI 1.23–1.89; P = 0.0003); AOR extreme obesity 2.22 (CI 1.27–3.87; P = 0.0003) 7–7.9 h reference category ≥9 h AOR obesity NS; AOR extreme obesity 2.53 (CI 1.10–5.78; P = 0.023) |
| Theorell-Haglow et al. [20•] | Cross-sectional Data source: Sleep and Health in Women Study (Sweden) |
400 F Age 29–70 years |
PSG recorded sleep duration | Inverse association between sleep duration and both waist circumference (Adj. β = –1.22 cm/h; P = 0.016) and sagittal abdominal diameter (Adj. β = –0.46cm/h; P = 0.001). |
| Watanabe et al. [21•] | Prospective 1 year Data source: workers of electric power company (Japan) |
31 477 M (mean age 40 ± 9 year old) and 3770 F (mean age 38 ± 9 years) | Self-reported sleep duration | M <5 h AOR of obesity 1.91 (CI 1.36–2.67; P < 0.001) 5–5.9 h AOR of obesity 1.5 (CI 1.25–1.8; P < 0.001) 7–8 h reference category F: NS |
| Bo et al. [22] | Prospective 6 years (Italy) | 1597 M, F Age 45–64 years |
Self-reported sleep duration | Each hour increase in total sleep time = 30% reduction in incident obesity (AOR 0.7/h; CI 0.57–0.86; P < 0.001) |
| Nishiura and Hashimoto [23•] | Prospective 4 years Annual health screen at a gas company (Japan) |
2362 M Age 40–59 years |
Self-reported sleep duration | <6 h AOR of obesity 2.46 (CI 1.41–4.31; P = 0.011) 7–7.9 h reference category ≥8 h NS |
| Hairston et al. [24•] | Prospective 5 years Three communities from the IRAS Family Study (USA) |
322 M, F African–Americans and 775 M, F Hispanic Americans Age 18–81 years |
Self-reported sleep duration | Age <40 years ≤5 h increase in BMI (+1.8 kg/m2, P < 0.001), SAT (+41 cm2, P < 0.0001), and VAT (+13cm2, P < 0.01) 6–7 h reference category ≥8 h increase in BMI (+0.8 kg/m2, P < 0.001), SAT (+20 cm2, P < 0.01), and VAT (+6 cm2, P < 0.05) Age >40: NS |
| Hayes et al. [25•] | Cross-sectional study Data source: Cleveland Family Study (USA) |
561 M, F Mean age 44.5 ± 16.1 years |
PSG recorded sleep duration | Each hour decrease in total sleep time: 6% increase in leptin levels (P = 0.01) 14% increase in visfatin levels (P = 0.02) Each hour decrease in REM sleep: 15% increase in leptin levels (P = 0.01) 31% increase in visfatin levels (P = 0.05) |
In each study, the association is expressed as higher probability or adjusted odds ratio (AOR) of obesity (BMI ≥30kg/m2) or increased waist circumference. Studies were conducted in different geographical regions. Sleep duration was self-reported or measured by overnight polysomnography (PSG). Adj. β, adjusted beta coefficient; CI, confidence interval; F, female; IRAS, Insulin Resistance Atherosclerosis Study; M, male; NS, not significant; REM, rapid eye movement; SAT, subcutaneous adipose tissue; VAT, visceral adipose tissue.