Physical activity and outcomes in Japanese patients with chronic obstructive pulmonary disease: From the Ishinomaki COPD Network registry

Background: Low physical activity levels are associated with an increased risk of exacerbations and all-cause mortality in patients with chronic obstructive pulmonary disease (COPD); however, evidence is limited in a population with a low frequency of exacerbations, such as the Japanese population. This study investigated the effects of physical activity on outcomes in Japanese patients with COPD. Methods: We conducted a prospective observational study in a cohort of Japanese patients with COPD between April 2018 and July 2020. Characteristics, frequency of exacerbations, and mortality were assessed during the 1- year follow-up period. Logistic regression analysis evaluated the relationship between physical activity and outcomes. Results: A total of 309 patients (294 males; median age, 75 years) with stable COPD were included, and 307 completed follow-up. Patients with lower levels of physical activity were older, and showed increased airflow obstruction, limited exercise capacity, increased dyspnea, depressive state, poor health status, muscle weakness, and more information needs for the disease. Patients with high levels of physical activity had a lower risk of exacerbation, including hospital admission, compared to those with low levels of activity (odds ratio [OR], 0.46; 95 % confidence interval [CI], 0.22-0.97; and OR, 0.21; 95 % CI, 0.09-0.50, respectively). High physical activity was associated with a reduced risk of all-cause mortality (OR, 0.07; 95 % CI, 0.01-0.55) and respiratory mortality (OR, 0.16; 95 % CI, 0.02-1.47). Conclusions: These findings showed that higher physical activity is associated with better clinical outcomes, even in a COPD population with a low frequency of exacerbations.