Residential Green and Blue Space, the Natural Environment, Genetic Susceptibility, and Incident COPD.

Background: Although cigarette smoking is the predominant risk factor for chronic obstructive pulmonary disease (COPD), environmental exposures and genetic susceptibility also contribute to disease risk, yet their joint effects remain unclear. We therefore prospectively examined the associations of residential green and blue space and the natural environment (GBN) with incident COPD across levels of genetic susceptibility. Methods: This population-based prospective cohort study included 385,502 UK Biobank participants. Residential GBN exposures within 300 m and 1000 m buffers were assessed. Genetic susceptibility was quantified using a polygenic risk score based on COPD-associated variants identified in a genome-wide association study. Cox proportional hazards models estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations between GBN exposures, genetic risk, and incident COPD. Gene-environment interactions were evaluated on multiplicative and additive scales. Results: Higher exposure to green space and the natural environment was associated with a lower risk of COPD (green space: HR = 0.87 [95% CI, 0.83-0.92], natural environment: HR = 0.83 [95% CI, 0.78-0.87] for the 1000 m buffer). Associations with blue space were weak and inconsistent. The natural environment exposure was inversely associated with COPD risk across genetic risk strata, with no significant multiplicative or additive interactions observed. Conclusion: Greater residential exposure to green space and the natural environment was associated with lower COPD risk, with no evidence that genetic susceptibility modified these associations, highlighting the potential role of environmental interventions in COPD prevention.