Volume 16, Issue 3, Summer 2004
Biographies of CHS women's health researchers
Diana Buist, assistant scientific investigator, is an epidemiologist interested in breast cancer and osteoporosis/fracture risk who joined CHS in 1996. She is the principal investigator of the Breast Cancer Surveillance Project, which seeks to improve the effectiveness of breast cancer screening by linking automated data on breast cancer risk factors, mammography, and cancer outcomes (see CHS Offline, Spring 2001). Two key surveillance analyses showed that: 1) higher breast density adversely affects mammography accuracy; and 2) hormone therapy use among postmenopausal women increases breast density. Buist and colleagues are following up on these findings with a study that examines whether stopping hormone therapy one or two months prior to a mammogram decreases breast density and thus, reduces a woman's likelihood of being called back for more testing.
In a separate study of hormone therapy "diffusion"—defined as the extent to which research results make their way into practice—Buist and colleagues compared rates of hormone therapy use among five HMOs over two time periods: 3 1/2 years before, and 6 months after, the July 2002 release of the results from the Women's Health Initiative (WHI) trial of estrogen-plus-progestin therapy. This trial was stopped early due to findings that use of this drug among women aged 50 to 79 increased the risk of heart attack, stroke, and breast cancer. Buist and colleagues found that rates of hormone therapy use dropped dramatically immediately following release of these findings (see graph below).
Research by Diana Buist, PhD, and colleagues showed the percent of
combination
hormone therapy users at five HMOs who discontinued use after
release of the WHI
results in July 2002(by month through December 2002).
Buist also conducts research pertaining to: 1) bone mineral density and breast cancer risk; 2) breast cancer treatment and survival; and 3) the influence of body mass index and tumor markers on the risk of breast cancer recurrence.
Andrea LaCroix, a CHS investigator since 1989, is an epidemiologist interested in women's health, particularly issues related to osteoporosis, cardiovascular disease, and aging. In 1996, LaCroix became a co-principal investigator of the Women's Health Initiative (WHI) Coordinating Center at Fred Hutchinson Cancer Research Center, while remaining a part-time senior investigator at CHS. As a member of the writing group for the WHI investigators, she played an integral role in reporting the results of the landmark WHI randomized trial of estrogen-plus-progestin therapy that appeared in the Journal of the American Medical Association in 2002.
At CHS in the mid-1990s, principal investigator LaCroix collaborated with Buist and Newton on the EnPOWER project. This project surveyed patients and providers about their attitudes and beliefs toward hormone therapy, and developed and evaluated a hormone therapy workbook designed to help women make informed decisions about whether to use hormone therapy. This workbook was eventually shared with women nationwide through publication on the Web site for the Centers for Disease Control and Prevention.
LaCroix was principal investigator on two CHS randomized trials related to fracture prevention. The first showed that the medication alendronate was effective in preventing clinical fractures, and the second showed that thiazide diuretics, medications commonly taken for high blood pressure, preserved bone density in older adults. LaCroix is currently collaborating with Newton on a randomized trial evaluating whether a certain medication in the class of drugs called selective estrogen receptor modulators (SERMs) prevents fractures and/or breast cancer.
LaCroix is also collaborating on studies exploring: the interaction of hormone therapy and genetics on the risk of cardiovascular events; hormone therapy diffusion; contraception and bone density; and alternative therapies for menopause.
Katherine Newton, associate scientific investigator, joined CHS in 1992. Newton is interested in mid-life and older women's health, with a particular emphasis on menopause and chronic disease epidemiology and prevention. She played a major role in the EnPOWER study, along with LaCroix and Buist (see LaCroix biography). According to the EnPOWER patient survey, 68 percent of Group Health women aged 45 to 65 had tried alternative treatments for menopausal symptoms. These data provided partial impetus for Newton's proposal "Alternative Therapies for Menopause," also called the HALT study.
This ongoing randomized trial, to be completed in August, compares the effects of three alternative treatments, hormone therapy, and placebo on the frequency and intensity of menopausal symptoms, such as hot flashes and night sweats. The three alternative treatment arms are: 1) Black cohosh, an herb commonly used by naturopaths to treat menopausal symptoms; 2) Progyne, a combination botanical formula with 10 active ingredients, one of which is black cohosh; and 3) Progyne plus dietary instruction to increase soy protein intake.
HALT is Newton's first experience as a principal investigator on a randomized clinical trial and she views the recruitment of 351 women over a two-year period as one of her largest professional accomplishments to date. "What I say about HALT is that if the learning curve had been any steeper, I would have fallen over backwards," jokes Newton. Consider, for example, that in the middle of recruitment for HALT, the Women's Health Initiative trial of combined hormone therapy was terminated because of an unfavorable risk-benefit profile for hormone therapy. All of the HALT participants, some of whom had been randomized to hormone therapy, had to be re-consented for the trial.
Newton continues to pursue her interest in hormone therapy under the auspices of a new diffusion grant looking at changes in hormone therapy use, and in patient/provider attitudes and beliefs toward hormone therapy, following release of the WHI findings. Other current research relates to endometrial hyperplasia and the effect of a specific selective estrogen receptor modulator (SERM) on fracture and breast cancer risk.
Delia Scholes, senior scientific investigator, joined CHS in 1987. She is a reproductive women's health epidemiologist, with a particular interest in contraception and sexually transmitted diseases (STDs). Scholes and colleagues' groundbreaking work demonstrating the benefits of chlamydia screening led the U.S. Preventive Services Task Force to issue a new chlamydia screening guideline in 2000 (see CHS Research News, Summer 2002). She has co-led, along with Robert.S. Thompson, MD, in Group Health Cooperative's Department of Preventive Care, a randomized trial of strategies to increase guideline-recommended chlamydia screening at Group Health. She was also the principal investigator for a randomized trial of a tailored behavioral intervention that increased condom use among young women at risk for STDs and AIDS. Over the last ten years, Scholes has collaborated with researchers at the UW on several studies of urinary tract infections in women.
In a series of ongoing studies, Scholes and colleagues are examining the relationship between hormonal contraceptive use and bone mineral density among cohorts of young women. There is concern that some contraceptives, such as the injectable Depo-Provera (DP) and birth control pills, work by suppressing the production of estrogen, a hormone critical to the attainment and maintenance of peak bone mass. In a recently completed study of DP use and bone density among 14- to 18-year-old women, Scholes and colleagues found that DP users experience decreased bone density when compared to teens not using this contraceptive. However, this process appears to be reversed when women stop taking DP (see graph). Scholes recently received a $3.1 million grant to continue this work by evaluating the possible effects of birth control pills on bone density in women between the ages of 14 and 30.
Research by Delia Scholes, PhD, and colleagues showed the
average change in spine bone mineral density among adolescent
women who are Depo-Provera users, non-users, and discontinuers.
In a nice example of synergy among the group members, Scholes and collaborators in the Women's Health Investigator Program recently submitted a successful application to analyze data from the Women's Health Initiative on a putative relationship between depression and osteoporosis. One hypothesis is that chemical changes brought on by depression may adversely affect bone. This analysis, conducted among women aged 50 to 79, effectively taps into the various areas of expertise offered by members of the group—Scholes: bone density in younger women; LaCroix, Buist, and Newton: bone density in older women; Melville: depression.