Women's Health Study (WHS)
Lead Contact and/or Principal Investigator (PI):
- Julie Buring, Sc.D.
Brigham and Women’s Hospital
Harvard Medical School
Funded Since: 1993
Funding Source: NCI Extramural Program (Division of Cancer Prevention; CA047988) and the National Heart, Lung, and Blood Institute (NHLBI); HL043851 and HL080467
Year(s) of Enrollment: 1992-1995
The Women's Health Study (WHS) is a randomized, double-blind, placebo-controlled trial using a 2x2 factorial design, and conducted among 39,876 female health professionals in the United States. The WHS is sponsored by both the National Cancer Institute (NCI) and the National Heart, Lung, and Blood Institute (NHLBI). Participants were randomly assigned to either Vitamin E (600 IU every other day) or placebo; and to aspirin (100 mg every other day) or placebo. Approximately 1.75 million female health professionals were contacted by mail to determine if they were suitable for inclusion in the study. A 3-month run-in phase was performed to screen out those with poor compliance. Randomization, which began in February 1993 and ended in January 1996, was stratified on 5-year age groups. The primary endpoint was a decrease in the incidence of total malignant neoplasms of epithelial cell origin as well as a reduction in the risk of all important vascular events (a combined endpoint of nonfatal myocardial infarction, nonfatal stroke, and total cardiovascular death). Secondary endpoints included the individual components of the combined endpoints. Compliance was measured by replies to a questionnaire sent out every year.
Pre-randomization blood samples from 28,345 participants have been frozen and stored for biomarker and genetic analyses. DNA has been extracted and genome-wide association studies conducted for these samples. The WHS has been extended through March 2009 for additional observational follow-up of the cohort.