The number of Americans aged 65 and older is projected to double to 88.5 million by 2050 (55% women). The significant aging of the U.S. population creates a public health mandate to identify effective interventions for preserving the health and independence of older people, especially women. Compelling evidence over the past several decades supports the importance of physical activity (PA) for preventing cardiovascular (CV) and other chronic diseases, and preserving physical and cognitive health, in older adults. Yet, despite the steady emergence of evidence-based interventions for increasing PA in older adults, which could potentially be delivered at a population level, we lack large-scale randomized trial data showing that these interventions can prevent clinical CV events or impact the public's health. To address this critical gap, we propose to conduct a large-scale, randomized controlled pragmatic trial, the Women's Health Initiative Strong & Healthy (WHISH) trial. This pragmatic trial will be embedded in the large, race/ethnicity diverse, WHI Extension cohort, now aged 63-99 years, which is both novel and resource-efficient. The trial will test the hypothesis that a centralized public health intervention designed to increase and/or maintain PA to levels recommended for older U.S. adults will reduce major CV events (e.g., myocardial infarction (MI), stroke, and CVD death) in older women over ~4 years of follow-up. The study will also evaluate the safety of the intervention by examining risks of total clinical fracture, hi fracture, falls, and non-CVD mortality. Preliminary screening indicates that 50,500 WHI women will meet eligibility criteria; the PA intervention and usual activity comparison groups will eac contain ~25,250 participants (mean age ~80 years). We will use a randomized consent design, with the observational comparison group and non-consenters followed as usual within the WHI Extension study. The WHISH intervention builds upon evidence-based, state-of-the-science behavioral approaches and intervention components that have proven to be effective in increasing PA in older women, with innovative adaptive strategies to tailor the intervention. We will use an algorithm-driven interactive voice response (IVR) system, a technology of increasing familiarity to older adults, built to complement National Institute on Aging (NIA) Go4Life(R) Exercise & Physical Activity materials. The evidence-based IVR system provides tailored advice, with personalized feedback and a means for self-monitoring (logging activity) and personal goal setting. PA behavior will be monitored by self-reported questionnaire and an accelerometry substudy in both study groups. Based on observed rates in the WHI cohort, we project 80% power to detect a 12.5% effect size for major CV events over the follow-up period. The WHI infrastructure, combined with innovative, evidence-based methods to deliver the PA intervention at a population level, provides a unique opportunity to address the critical question, Can a public health PA intervention reduce CVD events in older women? Determining the answer to this question, using a resource-efficient, scalable intervention, has major public health significance.

Public Health Relevance

The doubling of the numbers of older U.S. women by 2050 creates a critical need to identify effective interventions for preserving the health and independence of this population group. The WHISH Trial will test the hypothesis that a centralized, public health intervention designed to improve physical activity levels will reduce major cardiovascular disease events in older women (ages 63-99 years) over about 4 years of follow-up. Determining whether a resource-efficient, easily delivered PA intervention can reduce the cardiovascular disease burden of older women has major public health significance.

National Institute of Health (NIH)
National Heart, Lung, and Blood Institute (NHLBI)
Research Project--Cooperative Agreements (U01)
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Stoney, Catherine
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Stanford University
Internal Medicine/Medicine
Schools of Medicine
United States
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Anderson, Garnet L; Burns, Carolyn J; Larsen, Joseph et al. (2016) Use of administrative data to increase the practicality of clinical trials: Insights from the Women's Health Initiative. Clin Trials 13:519-26