A nationwide cohort study on the association between past physical activity and neovascular age-related macular degeneration in an East Asian population

Importance: It has been suggested that physical activity (PA) is associated with reduced risk for early age-related macular degeneration (AMD). Systematic evaluation has been examining the association between lifestyle and neovascular AMD in an East Asian population, with a particular focus on past vigorous PA. Objective: To investigate the association between neovascular AMD and past PA, particularly a history of vigorous exercise, in the overall study population and among 2 a priori-defined subgroups. Design, Setting, and Participants: In this propensity score-matched cohort study, individuals between ages 45 and 79 years who were included in the South Korean National Health Insurance Service database from 2002 through 2013 were evaluated. Physical activity and incident neovascular AMD were recorded at baseline (2002-2003) and at follow-up (August 1, 2009, to December 31, 2013), respectively. Using a 1:1 propensity score-matched analysis, the incidence of neovascular AMD was compared using hazard ratios (HRs) for neovascular AMD between 105 980 participants who did and 105 980 who did not (no-PA) engage in vigorous PA. The data analysis was performed from April 19, 2017, to June 5, 2017. Exposures: Physical activity. Main Outcomes and Measures: Incident cases of neovascular AMD. Results: Of the 211 960 participants (92 036 [43.4%] women; mean [SD] age, 55.1 [7.8] years), neovascular AMD was detected at follow-up in 250 (0.24%) individuals who engaged in past vigorous PA and in 198 (0.19%) of those who did not (HR, 1.23; 95% CI, 1.02-1.49). In subgroup analysis, vigorous PA was associated with a greater HR for neovascular AMD in participants aged 45 to 64 years (HR, 1.30; 95% CI, 1.04-1.63) and in men (HR, 1.36; 95% CI, 1.09-1.69). In the high-PA (≥5 times/wk: HR, 1.54; 95% CI, 1.15-2.06) and moderate-PA (1-4 times/wk: HR, 1.28; 95% CI, 1.01-1.63) groups, there was a greater incidence of neovascular AMD in the vigorous PA than in the no-PA group for men; no association was found for women. Conclusions and Relevance: Self-reported past vigorous PA in men aged 45 to 64 years was associated with an increased risk for neovascular AMD. To our knowledge, no previous study has reported such an association; replication of the results would seem warranted to strengthen the likelihood of a cause and effect relationship.ope