Association between obesity and sleep disorders in postmenopausal women

To investigate the relationship between obesity and sleep architecture in postmenopausal women.

One hundred seven postmenopausal women from the Ambulatory of Integrative Treatment for Female Sleep Disorders were invited by telephone to participate in this study. Fifty-three completed the study. We included women aged 50 to 70 years, and excluded women on hormone therapy or missing data. The study consisted of two meetings, including a full-night polysomnography. Menopause status was confirmed by amenorrhea for at least 1 year. Anthropometric measurements included: body mass, height, body mass index (BMI), waist circumference, hip circumference, waist-to-hip ratio (WHR), and neck circumference. Participants were allocated into two groups according to BMI: nonobese group (BMI <30 kg/m) and obese group (BMI ≥30 kg/m).

The obese group had significantly (P < 0.01) increased values of BMI, neck circumference, waist circumference, and hip circumference. WHR was similar between the groups (P = 0.77). Obese participants had significantly increased values of respiratory disturbance index (16.4 vs 9.3 n°/h) and apnea-hypopnea index (14.2 vs 5.6 n°/h). Rapid eye movement sleep latency was positively correlated to body mass (r = P < 0.01), BMI (P < 0.01), and hip circumference (P = 0.01). WHR was negatively correlated to sleep efficiency (P = 0.03). The linear regression model showed that BMI (P < 0.01) and WHR (P < 0.01) were positive predictors of rapid eye movement sleep latency.

In postmenopausal women, high BMI and abdominal obesity are sources of sleep disturbances, decreasing deep sleep, and sleep efficiency, while increasing the risk of obstructive sleep apnea.