Moderating effect of depression on the relationship between subjective health and quality of life in patients with COPD

Chronic obstructive pulmonary disease (COPD) is a chronic disease that deteriorates quality of life (QoL). This study examined how depression moderates the influence of subjective health on QoL in COPD patients.

Data set from the 2014 and 2016 Korean National Health Examination Survey (KNHANES) was used. Subjects were 815 COPD patients, aged 41 to 80 years old. QoL was evaluated with EuroQol 5-dimension (EQ-5D). Depression was measured using the Patients Health Questionnaire-9 (PHQ-9). Moderation analysis was performed using depression as a moderator of the relationship between subjective health and QoL.

The mean EQ-5D index score of participants was 0.93. Disease-related (COPD) characteristic was not significantly related to QoL. The final model (model 3) in regression explained 33.1% of variance in QoL in COPD patients. Subjective health status was a very important factor influencing QoL. Subjective health status × depression interaction was significant for QoL after adjusting control variables. Depression moderated the association between subjective health and QoL in individuals with COPD.

Early screening and continuous care for depression in patients having COPD in the community could be helpful to alleviate depression and improve QoL.