What's Next for Women's Health Research?

by National Institute of Health

Is women's health relevant to the general health of everybody or should it stay rooted merely in women's health centers? That's the question the medical science community must now ask, according to Dr. Marianne Legato, who lectured recently at the National Institutes of Health. Dr. Legato, a cardiologist who founded and directs the Partnership for Gender-Specific Medicine at Columbia University's College of Physicians and Surgeons in New York City, said the answer is both simple and complicated: Gender matters.

"You never would imagine the scope and significance of the differences between men and women in all the systems of the body," Dr. Legato said. "Being male or female is not simply a question of hormones."

For example, the size, structure and function of the brain differs in women and men, Dr. Legato said. Whole brain volume and the corpus callosum (the broad, thick band containing millions of nerve fibers running from side to side in the brain) are about 20 percent larger in males than in females. Women, however, have more neural connections across the corpus callosum.

"The variations in the gross volume of the brain are most significant in the areas that have to do with mood and behavior," she explained. These differences could have implications for diagnosing and treating such disorders as depression.

Men and women also sometimes use different areas of the brain to perform the same tasks. For instance, when asked to use verbal memory skills, women activate the left hemisphere of the brain and men activate the right hemisphere. Dr. Legato said reaction time is slower in women, but accuracy is higher.

"What does it mean?" she asked. "Does it mean differences eventually in the way that we will educate and communicate with men and women? We don't know. Does it mean that there are real gender differences in ability? That's a hotly debated issue. What is clear is that in some instances men and women recruit different areas of their brain to perform equal tasks."

Differences Throughout the Body

The biological differences between men and women extend through many systems in the body. For example, bone mass in a woman peaks at a distinct age, usually when she is in her early 20s. By contrast, a man reaches his maximum bone density much more gradually and plateaus later, by age 30. A period of accelerated bone loss occurs in women at menopause and continues for about five years afterward. These differences could prove important to understanding such disorders as osteoporosis.

"What is not clear is whether the bone loss is related only to estrogen deficiency," Dr. Legato explained. "Counseling therefore could differ [for men and women] on how and when to adjust lifestyle to achieve and preserve maximum bone density."

A woman's cardiovascular system, too, is different from a man's. The size, shape and electrical systems of the heart all vary in some respects by gender. Women have faster heart rates than men. These differences could prove to be crucial considerations in preventing, diagnosing and treating heart disease, the nation's top killer of both sexes, Dr. Legato said.

The differences don't end there. Women experience pain in different ways than men do, females seem more prone to autoimmune disorders than do males, and a woman's responses to infection varies from a man's responses. Even some specific diseases, such as malaria and HIV/AIDS, manifest themselves differently in women and men, Dr. Legato noted. These variations - and others yet to be discovered - are why scientists should examine the emphasis placed on women's health in the past two decades, she said, and determine whether research has taken into account all aspects of female biology.

Moving Beyond the "Bikini View"

"What does women's health really mean?" Dr. Legato asked. "Does it go beyond the 'bikini view,' that is, breast health and reproductive biology?" She suggested that new forays into gender-specific research must take broader, multidisciplinary approaches and look at women across their entire lifespans.

The Agenda for Research on Women's Health for the 21st Century, a report prepared by the NIH Office of Research on Women's Health (ORWH) with the input of more than 1,500 women's health professionals and advocates in the US, reflects Dr. Legato's suggestion. Spanning behavioral and social as well as biomedical research, the agenda recommends addressing health issues across a woman's life, "from prenatal stages to the frail elderly." The report also emphasizes the importance of understanding both genetic and environmental factors in determining how diseases develop, grow and spread.

Major diseases - heart disease, cancer, mental disorders and musculoskeletal problems - top the agenda. Several "emerging directions for improving women's health" - such as prevention and disparities among diverse groups - are also suggested in the report. Experts are convinced that implementing such a comprehensive plan for women's health will profit everyone's health.

"The women's health movement is a movement that I think can and will bring benefits to all members of our society," concludes Dr. Vivian Pinn, NIH associate director for research on women's health and ORWH director.

About the Author

NIH is the nation's medical research agency - making important medical discoveries that improve health and save lives. The National Institutes of Health (NIH), a part of the U.S. Department of Health and Human Services, is the primary Federal agency for conducting and supporting medical research.