Anxiety and depression in patients with chronic obstructive pulmonary disease and obstructive sleep apnea: the overlap syndrome

Purpose Psychological symptoms are increasingly being noted in patients with chronic diseases. Currently, little evidence is available on the mental health of patients with overlap syndrome (OVS, chronic obstructive pulmonary disease plus obstructive sleep apnea). This study aimed to describe the prevalence and identify influencing factors of anxiety and depression in patients with OVS. Methods We recruited patients admitted for chronic obstructive pulmonary disease (COPD) from July 2018 to July 2019 who also underwent polysomnography tests to assess obstructive sleep apnea (OSA). COPD patients who had an apnea-hypopnea index (AHI) >= 5/h were defined as OVS. COPD patients who had an AHI < 5/h were identified as pure COPD. Questionnaires were administered to evaluate depression and anxiety in all subjects. We compared the differences in scores between patients with OVS and pure COPD. Results Two hundred and fifty-two patients were included, 180 (71%) patients had OVS, while only 72 patients had pure COPD. In the OVS group, 54% of the patients had depression, and 77% of the patients had anxiety. We found that patients with OVS had higher anxiety (8.00 (4.00, 10.00) vs. 6.00 (3.00, 9.00), p = 0.018) and depression (8.00 (4.00, 10.00) vs. 5.50 (2.25, 10.00), p = 0.022) scores than patients with pure COPD. A higher proportion of patients with hypertension (41% vs. 21%) and coronary heart disease (14% vs. 4%) were found in the OVS group. Chest pain, COPD Assessment Test (CAT) score, and OVS were independent risk factors for depression (P<0.05). A positive correlation was shown between anxiety and depression (r=0.638, p < 0.001). Conclusions Anxiety and depression were more severe in patients with OVS than in patients with pure COPD. More attention should be paid to the mental health of OVS patients.