Determinants of rapid exercise capacity decline in patients with COPD

Abstract

Background: Exercise capacity is important for characterising COPD patients and determining prognosis of the disease. Currently, little is known about the potential determinants of a rapid decline in exercise capacity, which may put patients at risk of poor prognosis. We aimed to identify characteristics that predict a rapid decline in exercise capacity. Methods: Patients from a prospective cohort study in the Netherlands and Switzerland were followed for 5 years. Exercise capacity was assessed with the 1-minute sit-to-stand (1-min STS) test at baseline and after 4 years. We included all patients who were able to perform the 1-min STS test at baseline (n=371). Rapid decliners were identified as patients whose number of STS-repetitions decreased ≥25% over these 4 years. We identified potential determinants and fit logistic regression models with the outcome as rapid decliner or not. Results: 57 patients were identified as rapid decliners. Baseline characteristics found to be independently and significantly associated with a rapid decline in exercise capacity were age (OR: 1.07, 95% CI 1.02 to 1.13; p=0.01) and physical activity (Longitudinal Ageing Study Amsterdam Physical Activity Questionnaire (LAPAQ) score, OR: 0.42, 95% CI 0.27 to 0.66; p 1 % predicted were not associated with a rapid decline in exercise capacity. Conclusions: We identified two potential determinants of rapid exercise capacity decline as measured by the 1-min STS test in patients with COPD, which could assist in the assessment of patient prognosis and identify patients who may benefit from pulmonary rehabilitation.