Heart disease overall is the major killer of women in the U.S.

"But most women will tell you they think it's cancer....We think of (heart disease) as a man's disease, but that's not really the case at all," according to Jean Wactawski-Wende.

Wactawski-Wende, clinical assistant professor of gynecology and obstetrics in the UB School of Medicine and Biomedical Sciences, spoke March 14 at UB at Sunrise, the university's community breakfast series.

She is co-principal investigator for the Buffalo portion of the Women's Health Initiative, an effort funded by the National Institutes of Health to investigate the causes of, as well as the effectiveness of various treatments for, coronary heart disease, breast and colorectal cancers, and osteoporosis in older women.

UB is one of 45 centers throughout the nation participating in the study, which aims to enroll 160,000 women ages 50-79. It is the largest trial ever conducted in the U.S., and has an overall budget of $625 million from the NIH.

The Women's Health Initiative is looking at the major causes of disease in women," and how those diseases can be prevented or delayed, said Wactawski-Wende. Up to age 60, there is little heart disease among women, probably because of the production of estrogen, "but within 10 years of menopause, you can see an increase in many diseases. These diseases have not been studied adequately," she said.

Three courses of treatment are offered through the study, which will track participants over nine years. Researchers will look at the effects of hormone replacement therapy on heart disease, dietary modification on breast and colorectal cancer, and calcium and vitamin D supplements on osteoporosis and bone fractures.

While hormone replacement therapy has been used for more than 30 years, there are questions about its risks and benefits, Wactawski-Wende noted. When the therapy was begun in the 1960s to help menopausal women with hot flashes and other symptoms, there was the recognition that there may be other benefits to be gained.

Among the benefits: women on hormones had less heart disease, she said. And while there are suspicions that hormones may increase the incidence of breast cancer, Wactawski-Wende said that issue remains unclear.

While chronic heart disease occurs 10 years later in women than in men, women experience more angina and cardiac failure, and their prognosis is worse. But among women taking hormones, the risk of heart attack is 40-50 percent less than that of the general population, Wactawski-Wende said. Researchers hope to find the answers to a number of questions concerning how estrogens act to prevent coronary heart disease, she said.

Women's Health Initiative participants also can join a dietary study that will look at the relationship between dietary fat and breast and colorectal cancer, Wactawski-Wende said. Participants in that study receive extensive dietary modification instruction, and are encouraged to consume no more than 20 percent of their calories from fat, reduce their saturated fat consumption to seven percent and eat at least five servings of fruit and vegetables a day.

Women's Health Initiative researchers also hope to learn more about the effects of calcium and vitamin D on bone loss. "Ninety-nine percent of the calcium in the body is in the bones. If you don't get enough orally, the body takes skeletal calcium," said Wactawski-Wende. "We're looking at calcium intake to see if we can improve calcium in the bones." Women do not get enough calcium, she said. The median intake of calcium is 600 milligrams a day, but women age 65 and older should be taking in 1,500 milligrams. Participants in the calcium and vitamin D trial will receive daily supplements of 1,000 milligrams of calcium combined with 400 milligrams of vitamin D to aid absorption of the mineral.

Participants are still being accepted into the Women's Health Initiative, Wactawski-Wende said. Researchers will be accepting women into the diet portion of the study through the summer of '96 and to the hormone replacement therapy program through February of '97. Some participants in those two studies also may be asked to join the calcium and vitamin D trial. Wactawski-Wende said the Buffalo portion of the Women's Health Initiative hopes to recruit 4,000 Buffalo-area women for the study.