Objective: The prevalence of obstructive sleep apnea (OSA) in women increases significantly after menopause. However, identifying at-risk women is difficult because they tend to underreport symptoms and their complaints may differ from those traditionally associated with OSA. We investigated whether OSA risk factors are associated with the presence of a "nontraditional" complaint, such as nocturnal enuresis, in postmenopausal women.
Methods: A cross-sectional study of postmenopausal women aged 50 to 79 years who participated in the Women's Health Initiative Observational Study and clinical trials (1993-2005) at 40 clinical centers in the United States was performed. Multiple variable logistic regression analysis was used to determine the association of OSA risk factors with nocturnal enuresis.
Results: A cohort of 2,789 women (1.7%) reported having nocturnal enuresis. Obesity (odds ratio [OR], 2.29; 95% CI, 2.00-2.62), snoring (OR, 2.01; 95% CI, 1.74-2.32), poor sleep quality (OR, 1.70; 95% CI, 1.52-1.91), sleep fragmentation (OR, 2.44; 95% CI, 2.14-2.79), daytime sleepiness (OR, 1.50; 95% CI, 1.33-1.68), and hypertension (OR, 1.13; 95% CI, 1.01-1.26) were associated with nocturnal enuresis. Each additional OSA risk factor in a predefined OSA score significantly increased the odds of having nocturnal enuresis in a dose-response fashion (OR of 1.38, 2.00, 2.80, 3.87, 5.10, and 7.02 for scores of 1-6, respectively) compared with no risk factors.
Conclusions: OSA risk factors are associated with nocturnal enuresis in postmenopausal women. Mechanisms relating nocturnal enuresis to OSA may include apnea-associated changes in intrathoracic pressure, leading to increased urine output. Questioning at-risk postmenopausal women presenting with nocturnal enuresis about other OSA risk factors should be considered.