Four-year mortality and physical activity in Japanese patients with chronic obstructive pulmonary disease

Background: Physical activity (PA) is associated with the risk of mortality in patients with chronic obstructive pulmonary disease (COPD); however, evidence is limited to the Japanese population. This study aimed to evaluate the effects of PA on long-term mortality in Japanese patients with COPD. Methods: We conducted a prospective observational study in a cohort of Japanese patients with COPD and assessed mortality during a 4-year follow-up period. The Cox proportional hazards model was used to evaluate the association between PA and mortality. Results: Among 309 patients (294 men; median age, 76 years), 287 completed follow-ups while 45 died. The allcause mortality rate was 27.5% in patients with low PA and 4.1% in those with high PA. Adjusted hazard ratios for all -cause mortality were associated with high PA. Conclusions: Higher PA levels are associated with a better prognosis across different settings and patient characteristics, even in Japanese patients with COPD.