Effect of structured physical activity on overall burden and transitions between states of major mobility disability in older persons: secondary analysis of a randomized trial

Authors: GILL, THOMAS - Yale University; GURALNIK, JACK - University Of Maryland; PAHOR, MARCO - University Of Florida; CHURCH, TIMOTHY - Pennington Biomedical Research Center; FIELDING, ROGER - Jean Mayer Human Nutrition Research Center On Aging At Tufts University; KING, ABBY - Stanford University; MARSH, ANTHONY - Wake Forest University; NEWMAN, ANNE - University Of Pittsburgh; PELLEGRINI, CHRISTINE - Northwestern University; CHEN, SHYH-HUEI - Wake Forest University; ALLORE, HEATHER - Yale University; MILLER, MICHAEL - Wake Forest University

Submitted to: Annals of Internal Medicine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/9/2016
Publication Date: 9/27/2016
Citation: Gill, T.M., Guralnik, J.M., Pahor, M., Church, T.S., Fielding, R.A., King, A.C., Marsh, A.P., Newman, A.B., Pellegrini, C.A., Chen, S., Allore, H.G., Miller, M. 2016. Effect of structured physical activity on overall burden and transitions between states of major mobility disability in older persons: secondary analysis of a randomized trial. Annals Of Internal Medicine. 165(12):833-840.

Interpretive Summary: The total time a patient is disabled likely has a greater influence on their quality of life than the initial occurrence of disability alone. We compared the effect of a long-term, structured physical activity program with that of a health education control intervention on the total proportion of patient assessments indicating major mobility disability (MMD) (that is, MMD burden) and on the risk for transitions into and out of MMD. We used the Lifestyle for Independence in Elders (LIFE) study data to examine this. A total 1,635 sedentary persons, aged 70 to 89 years, were randomly assigned to a structured physical activity program (n = 818) or a health education control group (n = 817) and followed for up to 3.5 years. We found that a structured physical activity program reduced the MMD burden for an extended period, in part through enhanced recovery after the onset of disability and diminished risk for subsequent disability episodes. These results further emphasize the importance of regular physical activity for older adults-- particularly those at risk of becoming disabled.

Technical Abstract: Background: The total time a patient is disabled likely has a greater influence on his or her quality of life than the initial occurrence of disability alone. Objective: To compare the effect of a long-term, structured physical activity program with that of a health education intervention on the proportion of patient assessments indicating major mobility disability (MMD) (that is, MMD burden) and on the risk for transitions into and out of MMD. Design: Single-blinded, parallel-group, randomized trial. (ClinicalTrials.gov: NCT01072500) Setting: 8 U.S. centers between February 2010 and December 2013. Participants: 1635 sedentary persons, aged 70 to 89 years, who had functional limitations but could walk 400 m. Intervention: Physical activity (n = 818) and health education (n = 817). Measurements: MMD, defined as the inability to walk 400 m, was assessed every 6 months for up to 3.5 years. Results: During a median follow-up of 2.7 years, the proportion of assessments showing MMD was substantially lower in the physical activity (0.13 [95% CI, 0.11 to 0.15]) than the health education (0.17 [CI, 0.15 to 0.19]) group, yielding a risk ratio of 0.75 (CI, 0.64 to 0.89). In a multistate model, the hazard ratios for comparisons of physical activity with health education were 0.87 (CI, 0.73 to 1.03) for the transition from no MMD to MMD; 0.52 (CI, 0.10 to 2.67) for no MMD to death; 1.33 (CI, 0.99 to 1.77) for MMD to no MMD; and 1.92 (CI, 1.15 to 3.20) for MMD to death. Limitation: The intention-to-treat principle was maintained for MMD burden and first transition out of no MMD, but not for subsequent transitions. Conclusion: A structured physical activity program reduced the MMD burden for an extended period, in part through enhanced recovery after the onset of disability and diminished risk for subsequent disability episodes.