Influence of changes in physical activity on frequency of hospitalization in chronic obstructive pulmonary disease

To evaluate whether changes in regular physical activity (PA) in patients with chronic obstructive pulmonary disease (COPD) affect the rate of hospitalizations for COPD exacerbation (eCOPD).

Five hundred forty-three ambulatory clinic patients being treated for COPD were prospectively identified. PA was self-reported by patients, and the level was established by the distance they walked (km/day) at least 3 days per week. Hospitalizations were recorded from hospital databases. All patients with at least a 2-year follow-up after enrollment were included in the analysis. The response variable was the number of hospitalizations for eCOPD within the 3-year period from 2 to 5 years after study enrollment.

Three hundred ninety-one survivors were studied. Mean forced expiratory volume in 1 s was 52% (±14%) of the predicted value. Patients who maintained a lower level of PA had an increased rate of hospitalization (odds ratio 1.901; 95% confidence interval 1.090-3.317). After having had the highest level of PA, those patients who decreased their PA in the follow-up showed an increasing rate of hospitalizations (odds ratio 2.134; 95% confidence interval 1.146-3.977).

Patients with COPD with a low level of PA or who reduced their PA over time were more likely to experience a significant increase in the rate of hospitalization for eCOPD. Changes to a higher level of PA or maintaining a moderate or high level of PA over time, with a low intensity activity such as walking for at least 3-6 km/day, could reduce the rate of hospitalizations for eCOPD.