Depressive Symptoms in Comorbid Obstructive Sleep Apnea and Insomnia: An Integrative Review

The purpose of this integrative review was to synthesize evidence concerning the relationship between comorbid obstructive sleep apnea and insomnia (OSA+I), and depressive symptoms. OSA and insomnia are common sleep disorders, recently comorbid OSA+I has been recognized as prevalent in adults. Although each sleep disorder increases the risk and severity of depressive symptoms, the effect of comorbid OSA+I on depressive symptoms remains unclear. A systematic search of PubMed, CINAHL, and PsycINFO identified 15 data-based studies. All the studies were observational with either a cross-sectional (n = 14) or a case-control design (n = 1). Study quality was assessed. Most of the studies (n = 14) indicated that comorbid OSA+I had an additive role on depressive symptoms. Insomnia appeared to have a more important role than OSA in increasing the severity of depressive symptoms in persons with comorbid OSA+I.