Clinical depression in untreated obstructive sleep apnea: examining predictors and a meta-analysis of prevalence rates

Objective/background: Patients with obstructive sleep apnea (OSA) experience daytime sleepiness, cognitive impairment and depressive symptoms. However, the measured prevalence of clinical depression in OSA using standardized clinical assessment is currently unclear. The aims of this study were to examine the prevalence of clinical depression and antidepressant use in untreated OSA patients, to examine predictors of depression, and to conduct an exploratory meta-analysis to determine the pooled prevalence of clinical depression in this population. Patients/methods: In sum, 109 consecutive patients with diagnosed OSA (mean age (SD) = 52.6 (12.1) years; 43.1% female) who presented to the sleep laboratory completed a structured clinical interview for depression (SCID-IV), the Hospital Anxiety and Depression Scale, the Pittsburgh Sleep Quality Index (PSQI), the Functional Outcomes of Sleep Questionnaire (FOSQ), the Assessment of Quality of Life Questionnaire (AQoL) and the Epworth Sleepiness Scale (EES). An exploratory meta-analysis was also conducted to quantify the risk of clinical depression in untreated OSA. Results: Twenty-five (22.7%) participants had clinical depression based on the SCID-IV, and 24.8% were using antidepressants. Those with clinical depression had significantly poorer sleep quality and impaired quality of life. In a regression model, quality of life impairment was most strongly associated with clinical depression. Results from the meta-analysis revealed a pooled prevalence of 23% of clinical depression in OSA patients across seven studies. Conclusion: Clinical depression and antidepressant use is common in patients with OSA. Depression was associated with reduced quality of life and poorer subjective sleep, however it was not associated with polysomnographic measures or daytime sleepiness. Whether CPAP treatment can alleviate the burden of clinical depression needs to be determined in future studies.