Predictors of symptoms of anxiety and depression in obstructive sleep apnea

To assess factors associated with anxiety and depression in patients with obstructive sleep apnea syndrome (OSAS).

The study was comprised of a postal survey with a hospital chart review. Questionnaires were mailed to 242 previously hospitalised patients with OSAS. We assessed anxiety and depression with the Hospital Anxiety and Depression scale (HAD). Scores on the two HAD scales (0-21 scale, higher scores represent poor health) were categorized as normal/borderline (< or =10), and corresponding to a clinical diagnosis of anxiety or depression (> or =11). In logistic regression analysis, we assessed the association with HAD scores > or =11, using variables from the chart review and self-reported data on demographics, disease history, smoking status, CPAP/BiPAP use, and daytime sleepiness as assessed with the Epworth Sleepiness Scale (ESS), as potential predictors.

One hundred and seventy-eight patients (74%) with mean (SD) age 55 (11) years and body mass index (BMI) of 31 (5) kgm(-2) responded to the questionnaire. In multivariate logistic regression analysis, only low compliance with CPAP therapy (odds ratio (OR) 5.60, P=0.005) predicted high level of anxiety, and low compliance with CPAP therapy (OR 3.59, P=0.03) and daytime sleepiness (OR 1.14 per unit increase in ESS score, P=0.02) were the only predictors of high level of depression.

High anxiety score was associated with non-compliance with CPAP therapy. High depression score was associated with daytime sleepiness and non-compliance with CPAP therapy.