Anxiety and its relationship to quality of life independent of depression in patients with obstructive sleep apnea.

OBJECTIVES The relationship between anxiety and obstructive sleep apnea (OSA) has not been well studied. We evaluated the factors associated with anxiety and whether anxiety is related to quality of life (QoL) independently of depression in OSA patients. METHODS Data were collected from adults with newly diagnosed, untreated OSA. The State-Trait Anxiety Inventory-State Scale (STAI-S), the Beck Depression Inventory (BDI), the Epworth Sleepiness Scale (ESS), and the Short Form 36 Health survey (SF-36) were used. Anxiety and depression were defined as high levels of anxiety symptoms (STAI-S score≥40) and depressive symptoms (BDI≥10), respectively. Associations between anxiety and OSA were analyzed using multiple linear regression analysis. RESULTS Of 655 OSA subjects included, the prevalence of anxiety and depression was 48.4% and 46.4%, respectively. The scores of STAI-S had strong correlations with BDI (r=0.676, p<0.001). Female sex (p<0.05), excessive daytime sleepiness (ESS≥10) (p<0.05), and a lower educational level (p<0.05) were identified as independent factors for predicting the presence of anxiety in OSA patients. The severity of OSA measured by the apnea-hypopnea index or respiratory distress index was not related to comorbid anxiety. In linear regression analysis, both anxiety (ß=-10.196, p<0.001) and depression (ß=-16.317, p<0.001) were independently associated with lower SF-36 scores in OSA patients. CONCLUSIONS The presence of anxiety can be predicted by female sex, daytime sleepiness, and a lower educational level. Both anxiety and depression were independently associated with a lower QoL in OSA patients.