Prolonged leisure time television watching as a risk factor for chronic obstructive pulmonary disease: Insights from Mendelian randomization

Leisure sedentary behaviors are associated with an increased risk of chronic obstructive pulmonary disease (COPD), but whether this relationship is causal remains unknown. This study aimed to identify genetic determinants associated with leisure sedentary behaviors and estimate their potential causal effect on COPD risk. COPD case-control data were obtained from the Finnish biobank. Genome wide association analyses of leisure television watching, leisure computer use, and driving behavior in the UK Biobank identify 110, 82 and 6 genetic loci (P ＜ 5 × 10-8), respectively. A 2-sample Mendelian randomization (MR) analysis estimated a causal relationship between a 1.5-hour increase in television watching and a rise in COPD risk (OR = 2.725, 95% CI = 1.989-3.777, P = 7.113 × 10-10). This relationship persisted independently of age at smoking initiation, daily cigarette consumption, educational years, and body mass index in comprehensive MR analyses. However, multivariate MR analyses showed that genetically predicted leisure time spent on computers and driving did not robustly influence COPD risk. In conclusion, this MR study suggests that a genetic predisposition for prolonged time spent watching television significantly increases the risk of COPD, corroborating findings from observational studies.