Effect of Structured Physical Activity on Respiratory Outcomes in Sedentary Elderly Adults with Mobility Limitations.

Abstract

To evaluate the effect of structured physical activity on respiratory outcomes in community-dwelling elderly adults with mobility limitations. Multicenter, randomized trial of physical activity vs health education, with respiratory variables prespecified as tertiary outcomes over an intervention period of 24-42months. Physical activity included walking (goal of 150min/week) and strength, flexibility, and balance training. Health education included workshops on topics relevant to older adults and upper extremity stretching exercises. Lifestyle Interventions and Independence in Elders (LIFE) Study. Community-dwelling persons aged 70-89 with Short Physical Performance Battery scores less than 10 (N=1,635). Dyspnea severity (defined as moderate to severe according to a Borg index >2 immediately after a 400-m walk), forced expiratory volume in 1second (FEV1) (<lower limit of normal (LLN) defined low breathing capacity), and maximal inspiratory pressure (MIP) (<LLN defined respiratory muscle weakness) were assessed at baseline and 6, 18, and 30months. Hospitalization for exacerbation of obstructive airways disease (EOAD) and pneumonia was also ascertained over the 42-month follow-up period. The randomized groups were similar in baseline demographics, including mean age (79) and sex (67% female). The effect of physical activity on dyspnea severity, FEV1, and MIP was no different from that of health education but was associated with higher likelihood of respiratory hospitalization, significantly for EOAD (hazard ratio (HR)=2.34, 95% confidence interval (CI)=1.19-4.61, P=.01) and marginally for pneumonia (HR=1.54, 95% CI=0.98-2.42, P=.06). In older persons with mobility limitations, physical activity was associated with higher likelihood of respiratory hospitalization than health education, but differences in dyspnea severity, FEV1, and MIP did not accompany this effect-indicating that higher hospital use could be attributable to greater participant contact.