A physical activity intervention to treat the frailty syndrome in older persons-results from the LIFE-P study

Abstract

Background: The frailty syndrome is as a well-established condition of risk for disability. Aim of the study is to explore whether a physical activity (PA) intervention can reduce prevalence and severity of frailty in a community-dwelling elders at risk of disability.

Methods: Exploratory analyses from the Lifestyle Interventions and Independence for Elders pilot, a randomized controlled trial enrolling 424 community-dwelling persons (mean age=76.8 years) with sedentary lifestyle and at risk of mobility disability. Participants were randomized to a 12-month PA intervention versus a successful aging education group. The frailty phenotype (ie, ≥3 of the following defining criteria: involuntary weight loss, exhaustion, sedentary behavior, slow gait speed, poor handgrip strength) was measured at baseline, 6 months, and 12 months. Repeated measures generalized linear models were conducted.

Results: A significant (p = .01) difference in frailty prevalence was observed at 12 months in the PA intervention group (10.0%; 95% confidence interval = 6.5%, 15.1%), relative to the successful aging group (19.1%; 95% confidence interval = 13.9%,15.6%). Over follow-up, in comparison to successful aging participants, the mean number of frailty criteria in the PA group was notably reduced for younger subjects, blacks, participants with frailty, and those with multimorbidity. Among the frailty criteria, the sedentary behavior was the one most affected by the intervention.

Conclusions: Regular PA may reduce frailty, especially in individuals at higher risk of disability. Future studies should be aimed at testing the possible benefits produced by multidomain interventions on frailty.

Keywords: Clinical trials.; Frailty; Physical activity; Physical function; Successful aging.

© The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Figures

Figure 1.

Results from general linear models showing the prevalence of frailty at the different study visits according to randomization group. Results are reported as means (95% CI). Gender (stratifying variable for randomization), number of frailty criteria at the baseline (A) or prevalence of frailty at the baseline (B), and diabetes are included as covariates of the model. CI = confidence interval.

Figure 2.

Estimated effects of the intervention on the mean number of frailty criteria according to specific subgroups. Results are reported as means (95% CI). Estimates represent the average of the differences of mean levels between SA and PA groups over 6- and 12-mo visits obtained from a contrast estimated within a mixed effects model for the repeated frailty outcomes. Each model contained a prerandomization term representing the number of frailty conditions, an intervention effect, a visit effect, a term representing subgroup factor, and interactions between these last three terms. For the frailty subgroup analysis, the continuous baseline frailty outcome was dropped from the model. The reported p values for equality of difference between subgroups are obtained as a contrast from mixed effects model. CI = confidence interval; PA = physical activity; SA = successful aging.

Figure 3.

Estimated effects of the intervention on the prevalence of each of the frailty criterion according to the randomization group. Results are reported as percentages. The reported p values represent a test of the average prevalence at the month 6 and 12 visits in the PA vs the SA groups. Tests are adjusted for baseline levels for each frailty measure. PA = physical activity; SA = successful aging.