Determinants of change in physical activity during moderate-to-severe COPD exacerbation

BACKGROUND Data are scarce on patient physical activity (PA) level during exacerbations of chronic obstructive pulmonary disease (eCOPD). The objective of the study was to evaluate the level and determinants of change in PA during an eCOPD. MATERIALS AND METHODS We conducted a prospective cohort study with recruitment from emergency departments (EDs) of 16 participating hospitals from June 2008 to September 2010. Data were recorded on socioeconomic characteristics, dyspnea, forced expiratory volume in 1 second (FEV1%), comorbidities, health-related quality of life, factors related to exacerbation, and PA in a stable clinical condition and during the eCOPD episode. RESULTS We evaluated 2,487 patients. Common factors related to the change in PA during hospital admission or 7 days after discharge to home from the ED were lower PA at baseline and during the first 24 hours after the index evaluation. Age, quality of life, living alone, length of hospital stay, and use of anticholinergic or systemic corticosteroids in treating the exacerbation were associated with the change in PA among hospitalized patients. Predictors of change among patients not admitted to hospital were baseline FEV1% and dyspnea at rest on ED arrival. CONCLUSION Among the patients evaluated in an ED for an eCOPD, the level and change in PA was markedly variable. Factors associated with exacerbation (PA 24 hours after admission, medication during admission, and length of hospital stay) and variables reflecting patients' stable clinical condition (low level of PA, age, quality of life, FEV1%) are predictors of the change in PA during a moderate-to-severe eCOPD.