The Women’s Health Initiative is in the business of finding out the truth. For more than two decades, its investigators have been putting theories to the test, with results that have made a crucial difference to women’s health.
Now, WHI may be about to do it again with the launch of two large randomized controlled trials – the first in 10 years – designed to discover the health benefits (or risks) of two popular supplements, cocoa and multivitamins, as well as better understand how physical activity impacts the health of older women.
“These studies could have a lot of public health significance,” said Dr. Lesley Tinker, a staff scientist with the WHI’s Clinical Coordinating Center, based at Fred Hutchinson Cancer Research Center. “The WHI has provided researchers with a wealth of data over the years that have led to breakthrough health findings. With these two trials, we have the opportunity for additional groundbreaking results.”
Launched in 1993, the National Institutes of Health-sponsored WHI recruited more than 160,000 women to participate in one of the largest and most ambitious prevention studies ever conducted in the U.S.
Since that time, it has produced a number of groundbreaking results, including the landmark 2003 study that linked combined hormone replacement therapy to an increased incidence of cardiovascular disease, stroke and breast cancer.
The Cocoa Supplement and Multivitamin Outcomes Study, dubbed COSMOS, will examine two intriguing questions: Does cocoa extract reduce the risk of heart disease and stroke in older adults, and does taking multivitamins help reduce the risk of cancer?
“There’s evidence that shows that cocoa extracts may reduce the risk of cardiovascular disease and multivitamins may reduce the risk of cancer,” said Tinker. “But there have been no previous large-scaled randomized trials for cocoa extracts in men or women or in multivitamins for women.”
In the study, half of the 12,000 WHI COSMOS participants will take pills packed with an extract of cocoa beans that include flavanols for a total of four years and half will take a placebo for the same amount of time. None of the pills will taste like chocolate. Researchers will then determine whether the cocoa pills helped to reduce the overall number of heart attacks, strokes and surgeries to clear clogged arteries.
“At first a lot of people were really jazzed about COSMOS because they thought, ‘Oh, chocolate,’” said Tinker. “But it’s adamantly not a chocolate study. Participants will be receiving capsules of cocoa extract.”
Dr. Garnet Anderson, principal investigator for the WHI, will partner with researchers at the Brigham and Women’s Hospital and Harvard Medical School in Boston for the COSMOS study. Men from the Boston area will also be recruited for the study.
“There are a variety of studies of varying quality suggesting people who eat chocolate, particularly dark chocolate, may have better outcomes,” Anderson said. “This study will test whether [cocoa] flavanols can affect the rate of heart disease.”
Participants in COSMOS will also be randomized to receive a multivitamin supplement or placebo, after which researchers will determine whether the multivitamin supplement helped to reduce the risk of cancer.
Anderson said she was particularly excited about this arm of the COSMOS study, which could become “a definitive trial of multivitamins.”
“Half of the U.S. adult population is taking supplements,” she said. “If that many people are taking them, we should know what their health effects are – good or ill.”
“There has been a large scale randomized study in men that did suggest some benefits for cancer prevention, but there have been no randomized trials done in women,” Tinker said. “Clinical trials offer more of a definitive answer.”
Tinker added that both the COSMOS studies will fill a much-needed knowledge gap.
“Cocoa extract and multivitamins are promising interventions for reducing cardiovascular disease and cancer, but we need conclusive evidence one way or the other,” she said.
The second study, called the Women’s Health Initiative Strong and Healthy Study, or WHISH, will determine if postmenopausal women who increase their physical activity – via walking and strength, balance and flexibility activities – can lower their risk of heart disease and increase their ability to live independently.
“Physical function declines as we age, but the decline may be less of a slope if we keep physically active,” said Tinker.
The WHISH study will include about 52,000 participants, half of whom will receive guidance on safe ways to exercise through brochures, DVDs, websites and telephone coaching.
Fred Hutch’s Dr. Charles Kooperberg, principal investigator, will partner with researchers from Stanford and the University of California at San Diego for the study, which will also last four years.
WHI currently follows about 87,000 women, about 54 percent of the original volunteer group.
Both Tinker and Anderson lauded the decades-long contributions of these participants, whose involvement has become the backbone of over 1,000 WHI scientific papers and more than 340 ancillary studies.
“Some of our participants are now 101 years old,” said Tinker. “And they are still active in the sense of responding.”
“They are wonderfully committed women,” added Anderson.
Diane Mapes is a staff writer at Fred Hutchinson Cancer Research Center. She has written extensively about health issues for NBC News, TODAY, CNN, MSN, Seattle Magazine and other publications. A breast cancer survivor, she also writes the breast cancer blog doublewhammied.com. Reach her at firstname.lastname@example.org.