Mendelian Randomization Study on the Relationship between Depression and Chronic Obstructive Pulmonary Disease

Objective This study aims to investigate the causal relationship between depression and chronic obstructive pulmonary disease (COPD), as well as the risk factors for COPD, using Mendelian Randomization (MR) method.Methods In this study, we utilized large-scale Genome-Wide Association Study (GWAS) data and selected genetic variants strongly associated with depression as instrumental variables. We performed two-sample Mendelian Randomization (MR) analysis using inverse variance weighted (IVW) method, MR-Egger regression, maximum likelihood method, simple median method, and weighted median method.Results The MR analysis revealed a causal association between depression and COPD (IVW: OR=1.018, 95%CI=1.009-1.026, P<0.001). Additionally, there was a causal relationship between depression and outdoor tobacco smoke exposure (IVW: OR=1.044, 95%CI=1.021-1.067, P<0.001). However, no significant causal effects were observed between depression and indoor tobacco smoke exposure or air pollution.Conclusion Individuals with depression have a higher risk of developing COPD compared to the general population, which may be attributed to increased exposure to outdoor tobacco smoke.