Sleep disorders, including insomnia, are risk factors for weight gain. However, few epidemiological studies have investigated the association of anthropometric markers with insomnia as an outcome.
In this observational, cross-sectional study, we assessed the association of 3 different anthropometric indices with acute and chronic insomnia. We used data from 13 389 French adults (mean age= 51.9 ± 13.1 years; 70.3% women) enrolled in the NutriNet-Santé-Biobank cohort. Body weight, height, waist and hip circumference were measured once during a clinic visit (2011-14). Body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) were the main predictors. Acute (past 8 days) and chronic (≥3 months) insomnia were assessed in 2014 via a self-report questionnaire. We fit multivariable logistic regression models providing odds ratios (OR) and 95% confidence intervals (CI).
Overweight (25.0 ≤ BMI < 30.0 kg/m2) and general obesity (BMI ≥ 30.0 kg/m2) appeared to have an inverse association with acute insomnia only among men (overweight: OR= 0.80, 95% CI: 0.70, 0.92; obesity: OR= 0.78, 95% CI: 0.63, 0.98). Obesity assessed by BMI and WHR appeared to be positively associated with chronic insomnia only among women (BMI: OR= 1.23, 95% CI: 1.04, 1.45; WHR: OR= 2.24, 95% CI: 1.07, 4.72). WC did not display any significant associations in either sex.
These cross-sectional results revealed sex-specific associations of overweight/obesity with different types of insomnia, and merit confirmation longitudinally with objectively assessed sleep parameters. Nonetheless, the findings reinforce the critical importance of joint health behaviour promotion.