This is a 3x2x2 factorial design clinical trial in postmenopausal women, ages 50-79, to test the overall health impact of three major treatment strategies in a broad and representative group of mature women. These strategies are estrogen replacement therapy (ERT) -- with or without progesterone, low-fat diet, and calcium/vitamin D (Ca/VitD) supplementation. Treatments will be compared with placebo (versus ERT), usual diet (versus low-fat diet), and placebos for Ca/Vit D. Special efforts to include minority and lower socioeconomic strata women will be emphasized to increase generalizability of findings.

The second major objective is to conduct an observational study of a large group of postmenopausal women, ages 50-79 to determine risk factors for major morbidities and mortality in this age group.

Secondary objectives of the WHI are discussed in the Request For Proposal, and many others can be suggested. We consider the most important secondary objectives to be these:

To conduct the clinical trial and the observational study cost-efficiently.
To determine disease-specific effects of the individual interventions of the clinical trial, and to determine combined effects on disease-specific endpoints in participants who receive multiple interventions. For example, do women receiving ERT plus Ca/Vit D supplementation experience a lower incidence of osteoporotic-related fractures compared with women on ERT alone? The factorial design of this trial should permit analysis of individual therapeutic effects as well as multiple therapies taken simultaneously.
To assess multiple disease endpoints, both fatal and non-fatal, to derive a measure of overall health impact of the interventions in the clinical trial.
In the observational study, to assess the effects of spontaneous changes in risk factors as predictors of morbidity and mortality in this population.
To assess all types of health effects, including psychosocial effects and quality of life, in the women in the clinical trial and the observational study.
To create a source of data and biologic samples that can be used to unearth new risk factors and/or biomarkers for disease.
For the hormone replacement therapy arm of the clinical trial, to test whether ERT, as well as progesterone ERT, reduces the incidence of coronary heart disease and other cardiovascular disease.
To assess whether estrogen replacement increases the risk of endometrial and/or breast cancer and whether these are reduced by the estrogen-progesterone combination.
For the low-fat dietary component, to test whether a low-fat diet pattern reduces the incidence of breast cancer and, separately, colorectal cancer. A subsidiary aim is to test whether the low-fat diet pattern reduces the incidence of coronary heart disease.
To test whether supplementation with Ca and Vit D reduces the incidence of bone fractures. Secondarily, to test whether Ca/Vit D reduces the incidence of colorectal cancer; lowers blood pressure; and reduces the incidence of breast cancer.
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last updated:Tue Aug 25, 2009 7:15 AM