|TROMBETTI, ANDREA - Geneva University Hospital|
|HARS, MELANY - Geneva University Hospital|
|HSU, FANG-CHI - Wake Forest University|
|REID, KIERAN - Jean Mayer Human Nutrition Research Center On Aging At Tufts University|
|CHURCH, TIMOTHY - Pennington Biomedical Research Center|
|GILL, THOMAS - Yale University|
|KING, ABBY - Stanford University|
|LIU, CHRISTINE - Jean Mayer Human Nutrition Research Center On Aging At Tufts University|
|MANINI, TODD - University Of Florida|
|MCDERMOTT, MARY - Northwestern University|
|NEWMAN, ANNE - University Of Pittsburgh|
|REJESKI, JACK - Wake Forest University|
|GURALNIK, JACK - University Of Florida|
|PAHOR, MARCO - University Of Florida|
|FIELDING, ROGER - Jean Mayer Human Nutrition Research Center On Aging At Tufts University|
Submitted to: Annals Of Internal Medicine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/23/2017
Publication Date: 3/6/2018
Citation: Trombetti, A., Hars, M., Hsu, F., Reid, K.F., Church, T.S., Gill, T.M., King, A.C., Liu, C.K., Manini, T.M., McDermott, M.M., Newman, A.B., Rejeski, J.W., Guralnik, J.M., Pahor, M., Fielding, R.A. 2018. Effect of physical activity on frailty: secondary analysis of a randomized controlled trial. Annals Of Internal Medicine. 168(5):309-316. https://doi.org/10.7326/M16-2011.
Interpretive Summary: This study examined whether a long-term, moderate-intensity physical activity program was effective in reducing frailty in sedentary older adults. Using data from the LIFE (Lifestyle Interventions and Independence for Elders) study, 1,635 participants aged between 70-89 years were evaluated at baseline and after 24 months of participating in a structured physical activity program or a health education program consisting of workshops on topics relevant to older adults. The major findings of this investigation revealed that the risk of frailty was not reduced in those participants who participated in the physical activity intervention. However, frail participants at baseline who were randomized to the physical activity program did reduce their risk for development of mobility disability. These findings support the beneficial effects of physical activity for frail older adults.
Technical Abstract: Background: Limited evidence suggests that physical activity may prevent frailty and associated negative outcomes in older adults. Definitive data from large, long-term, randomized trials are lacking. Objective: To determine whether a long-term structured moderate-intensity physical activity (PA) program is associated with lower risk of frailty and whether frailty status alters the effect of PA on the reduction in major mobility disability (MMD) risk. Design: Multicenter, single-blind, randomized trial. Setting: Eight centers in the United States. Participants: 1635 community-dwelling adults, age 70-89 years with functional limitations. Interventions: A structured moderate-intensity PA program incorporating aerobic, resistance, and flexibility activities or a health education program consisting of workshops and stretching exercises. Measurements: Frailty, as defined by the Study of Osteoporotic Fractures (SOF) index, at baseline, 6, 12, and 24 months, and MMD, defined as the inability to walk 400 m, for up to 3.5 years. Results: Over 24 months of follow-up, the risk of frailty (n=1623) was not significantly different in the PA group versus the health education group (adjusted prevalence difference, -0.021 [95%CI, -0.049 to 0.007]). Among the three criteria of the SOF index, the PA intervention was associated with improvement in the inability to rise from a chair criterion (adjusted prevalence difference, -0.050 [CI, -0.081 to -0.020]). Baseline frailty status did not modify the effect of PA on reducing incident MMD (P for interaction = 0.91). Limitation: Frailty status was not an entry criterion nor a randomization stratum. Conclusions: A structured, moderate-intensity PA program was not associated with a reduced risk of frailty over two years among sedentary community-dwelling older adults. The beneficial effect of PA on incidence of MMD did not differ between frail and non-frail individuals.