Dennis T. Villareal, M.D., Suresh Chode, M.D., Nehu Parimi, M.D., David R. Sinacore, P.T., Ph.D., Tiffany Hilton, P.T., Ph.D., Reina Armamento-Villareal, M.D., Nicola Napoli, M.D., Ph.D., Clifford Qualls, Ph.D., and Krupa Shah, M.D., M.P.H.
N Engl J Med 2011; 364:1218-1229March 31, 2011
BACKGROUND
Obesity exacerbates the age-related decline in physical function and causes frailty in older adults; however, the appropriate treatment for obese older adults is controversial.
METHODS
In this 1-year, randomized, controlled trial, we evaluated the independent and combined effects of weight loss and exercise in 107 adults who were 65 years of age or older and obese. Participants were randomly assigned to a control group, a weight-management (diet) group, an exercise group, or a weight-management-plus-exercise (diet–exercise) group. The primary outcome was the change in score on the modified Physical Performance Test. Secondary outcomes included other measures of frailty, body composition, bone mineral density, specific physical functions, and quality of life.
RESULTS
A total of 93 participants (87%) completed the study. In the intention-to-treat analysis, the score on the Physical Performance Test, in which higher scores indicate better physical status, increased more in the diet–exercise group than in the diet group or the exercise group (increases from baseline of 21% vs. 12% and 15%, respectively); the scores in all three of those groups increased more than the scores in the control group (in which the score increased by 1%) (P<0.001 for the between-group differences). Moreover, the peak oxygen consumption improved more in the diet–exercise group than in the diet group or the exercise group (increases of 17% vs. 10% and 8%, respectively; P<0.001); the score on the Functional Status Questionnaire, in which higher scores indicate better physical function, increased more in the diet–exercise group than in the diet group (increase of 10% vs. 4%, P<0.001). Body weight decreased by 10% in the diet group and by 9% in the diet–exercise group, but did not decrease in the exercise group or the control group (P<0.001). Lean body mass and bone mineral density at the hip decreased less in the diet–exercise group than in the diet group (reductions of 3% and 1%, respectively, in the diet–exercise group vs. reductions of 5% and 3%, respectively, in the diet group; P<0.05 for both comparisons). Strength, balance, and gait improved consistently in the diet–exercise group (P<0.05 for all comparisons). Adverse events included a small number of exercise-associated musculoskeletal injuries.
CONCLUSIONS
These findings suggest that a combination of weight loss and exercise provides greater improvement in physical function than either intervention alone. (Funded by the National Institutes of Health; ClinicalTrials.gov number, NCT00146107.)
The content of this article is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute on Aging or the National Institutes of Health.
Supported by grants (RO1-AG025501 and P30-DK56341 [Clinical Nutrition Research Unit], UL1-RR024992 [a Clinical and Translational Science Award], and DK20579 [Diabetes Research and Training Center]) from the National Institutes of Health. Dr. Hilton was supported by a postdoctoral fellowship (HD007434) from the Eunice Kennedy Shriver National Institute of Child Health and Human Development and a New Investigator Fellowship Initiative grant from the Foundation for Physical Therapy.
Disclosure forms provided by the authors are available with the full text of this article at NEJM.org.
No potential conflict of interest relevant to this article was reported.
We thank the participants; the staff of the Intensive Research Unit of the Institute of Clinical and Translational Sciences; Nicole Wright for study coordination; Stacie Metzger, Amelia Grant, and Ellen Frye for exercise training; and Kathy Obert, Laura Weber, and Cindi Inman for weight-loss training.
SOURCE INFORMATION
From the Division of Geriatrics and Nutritional Science (D.T.V., S.C., N.P., D.R.S., K.S.), the Program in Physical Therapy (D.R.S., T.H.), and the Division of Bone and Mineral Diseases (R.A.-V., N.N.), Washington University School of Medicine, St. Louis; and the Sections of Geriatrics (D.T.V.) and Endocrinology (R.A.-V.), New Mexico Veterans Affairs Health Care System; and the Divisions of Geriatrics (D.T.V.) and Endocrinology (R.A.-V.) and the Department of Mathematics and Statistics (C.Q.), University of New Mexico School of Medicine — both in Albuquerque.
Address reprint requests to Dr. Villareal at the New Mexico VA Health Care System, Geriatrics (111K), 1501 San Pedro Dr., Albuquerque, NM 87108, or atdennis.villareal@va.gov.
