Objective: Although estrogen may be linked to biological pathways that maintain higher physical function, the evidence is derived mostly from observational epidemiology and therefore has numerous limitations. We examined whether hormone therapy affected physical function in women 65 to 79 years of age at enrollment.
Methods: This study involves an analysis of the Women's Health Initiative randomized controlled trials of hormone therapy in which 922 nondisabled women who had previous hysterectomies were randomized to receive estrogen therapy or a placebo and 1,458 nondisabled women with intact uteri were randomized to receive estrogen + progestin therapy or a placebo. Changes in physical function were analyzed for treatment effect, and subgroup differences were evaluated. All women completed performance-based measures of physical function (grip strength, chair stands, and timed walk) at baseline. These measures were repeated after 1, 3, and 6 years.
Results: Overall, participants' grip strength declined by 12.0%, chair stands declined by 3.5%, and walk pace slowed by 11.4% in the 6 years of follow-up (all P values <0.0001). Hormone therapy, as compared with placebo, was not associated with an increased or decreased risk of decline in physical function in either the intention-to-treat analyses or in analyses restricted to participants who were compliant in taking study pills.
Conclusions: Hormone therapy provided no overall protection against functional decline in nondisabled postmenopausal women 65 years or older in 6 years of follow-up. This study did not address the influence of hormone therapy for women of younger ages.
Hormone therapy provided no overall protection against functional decline during 6 years of follow-up of nondisabled ostmenopausal women aged 65 to 79 years at enrollment. However, this study did not address the influence of hormone therapy for women of younger ages.
From the 1Department of Epidemiology, Drexel University School of Public Health, Philadelphia, PA; 2The Center for Health Research, Kaiser Permanente Northwest, Portland, OR; 3Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston MA; 4Department of Public Health and Preventive Medicine, Oregon Health and Science University, Portland, OR; 5School of Nursing, University of Washington, Seattle, WA; 6School of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX; 7Michigan State University College of Osteopathic Medicine, Detroit, MI; and 8Department of Epidemiology, University if Iowa, Iowa City, IA.
Received June 17, 2009; revised and accepted July 29, 2009.
Funding/support: The Women's Health Initiative program is funded by the National Heart, Lung, and Blood Institute, National Institutes of Health, US Department of Health and Human Services, through contracts N01WH22110, 24152, 32100-2, 32105-6, 32108-9, 32111-13, 32115, 32118-32119, 32122, 42107-26, 42129-32, and 44221. Additional funding for these analyses was provided by the National Institute on Aging (1 R03 AG031973-01) to Dr. Michael. Funding agencies had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; and preparation, review, or approval of the manuscript.
Financial disclosure/conflicts of interest: None reported.
Address correspondence to: Yvonne L. Michael, ScD, Deparment of Epidemiology and Biostatistics, Drexel University School of Public Health, Philadelphia, PA 19102. E-mail: firstname.lastname@example.org