SUSAN DENTZER: For the past decade there has been a dawning awareness that differences between the sexes play a surprising large role in health and disease.
Take heart disease. Research has shown that women are more likely than men to exhibit symptoms like shortness of breath and fatigue, rather than the classic chest pain. That fact has often led doctors to misdiagnose women's complaints. What's more many debilitating autoimmune diseases like multiple sclerosis affect women eight to nine times more frequently than men. Yet, much of medical research seldom took such sex based differences into account.
SUSAN DENTZER: Phyllis Greenberger heads the Society for Women's Health Research.
PHYLLIS GREENBERGER: One of the things that was not happening, which was actually documented in an earlier report of public health service report was that women were routinely being included in clinical trials. And that's medical research. And if you're not having women in medical research, then you're not going to have the answers to these conditions.
SUSAN DENTZER: As a result, Congress passed legislation in the early 1990's, ordering that women be included in federally-funded trials testing new medical treatments. But there is growing evidence that sex based differences are even more pervasive than previously thought. So the National Institute of Medicine issued a report called "Does Sex Matter?" Harvard immunologist Denise Faustman talked about the need to address the differences at a Washington press conference today.
DR. DENISE FAUSTMAN: For many, many years for the protection of women drugs were predominantly examined during the approval stages and different phases of clinical trials in men not women to protect women from possible side effects from being pregnant. So many of the drugs we have on the market efficacy in women isn't known even though they're prescribed equally to men and women.
SUSAN DENTZER: The IOM report said sex-based differences can be seen from woman to tomb starting at the cellular level.
DR. MARY-LOU PARDUE: Female cells are in many cases having more genetic information expressed than male cells.
SUSAN DENTZER: The report urged that the differences be taken into account more broadly at all levels in biomedical and health research.
GWEN IFILL: Joining me now is a member of the committee that produced today's report, Dr. Sally Shaywitz, a professor of pediatrics at the Yale University School of Medicine.
Welcome, Dr. Shaywitz.
SALLY SHAYWITZ: Thank you.
GWEN IFILL: So the bottom line in today's report is that men and women are different. What's the big deal?
SALLY SHAYWITZ: The big deal is that for the first time, we have solid evidence that sex matters, that sex is an important biologic variable that affects the health and well-being of people and that it becomes important to study sex differences. In the past, we've learned about sex differences as a byproduct of other research. But we've now been able to gather a corpus of evidence that shows that there are sex differences in the cell, at a molecular level, in organs, in organ systems, and sex differences that affect the health and well-being of people, so that we have matured enough in the study of sex differences to say that now is the time to really begin to study sex differences as important in and of themselves.
GWEN IFILL: But why now? A lot of the bits and pieces that you're describing we've discovered have been reported in various reports, but today it comes together in one report, which you all say is going to turn the corner. Why now?
SALLY SHAYWITZ: Well, why now is because the Institute of Medicine has done a thorough study and shown that at every level, there are important sex differences. But now we have to begin to design experiments so we can understand what do they mean? How can we best use this information to benefit the health and well-being of men and women?
GWEN IFILL: How many of the differences that you're talking about are the kind of hormonal differences we're all familiar with, and how many of them are physiological, biological, genetic?
SALLY SHAYWITZ: Well, that's the exciting thing about this report. This report was put together by the committee and understanding the biology of the sex and gender differences. In the past, people have focused, for example, on social and cultural explanations. But over the last several years, there's been a number of very exciting discoveries that have pointed to sex differences at very basic and fundamental biological levels. So the question is now, how can we use that information to further studies at this level, but also, to apply to the study of human health and disease?
GWEN IFILL: Which diseases are you talking about when you talk about studying specific diseases with an eye towards sex differences?
SALLY SHAYWITZ: Well, that's the exciting thing, is that because every cell has sex, and there are sex differences in every cell in the body and in every organ, we need to begin to study the cells at the basic level, but also expand that study and design studies so that we can find out about sex differences and disorders that affect the brain, the heart, the kidneys, liver. We know a great many. We know, for example, that there's a significant sex difference in the prevalence of many diseases and the severity of diseases.
GWEN IFILL: Which diseases, for example?
SALLY SHAYWITZ: Oh, heart disease, for example, what we call autoimmune diseases. Many of them, for example, rheumatoid arthritis, affect lupus, affect thyroid disease, affect primarily females. But there are some - a disorder called "Good Pastures," that affect primarily males.
GWEN IFILL: We're not just talking about diseases that have their root in reproductive production.
SALLY SHAYWITZ: That's really such an important point. The exciting thing is that these differences have been found in all cells and in oral organs and, in fact, in the brain. So that it has been known that, for example, that there are sex differences in the brain involving reproductive functions. But more recently we've discovered sex differences in the brain that controls many other functions, including how we behave and how we speak.
GWEN IFILL: Now we use this... Now that we know this report shows us an understanding of why this exists, how do we use the findings in this report to prevent disease?
SALLY SHAYWITZ: All right, well, I think we have to first go further. And in the report, there are a number of recommendations that talk about barriers, and we have to address those barriers so that we can apply this knowledge. One barrier is simple terminology. People use the terms "sex" and "gender" interchangeably -- and science and the scientific process would be benefited by having consistent use of the terms.
GWEN IFILL: Why are they different?
SALLY SHAYWITZ: Well, one explanation that I think... That I find very appealing is that if you were to ask an archaeologist, and that archaeologist would tell you, "well, to know the sex of an individual, I would look at their bones." But if I wanted to know their gender, I'd probably look at their artifacts. So...
GWEN IFILL: Go ahead.
SALLY SHAYWITZ: So that we would say that the sex of a male or a female really reflects their reproductive organs and the chromosomes that led to that reproductive status, whereas the gender of an individual-- male or female-- would more reflect how that person identifies, how they see themselves, and how society views that individual.
GWEN IFILL: You have done some extensive research on sex differences involving the brain. Explain that to me.
SALLY SHAYWITZ: Well, that's very exciting. It's been known for a long time, for example, that if a male compared to a female had a stroke involving the left side of their brain, if the stroke occurred in a male, that male would be much more likely than a female to have the detriment in their verbal ability compared to a female, but the question was, why? And what's now possible because of an exciting new technology called functional magnetic resonance imaging. And essentially uses... If you had an MRI because you've had a headache or anything, it's the same scanner but a smart version. And you can have people in the scanner doing tasks. You can ask them, "do these two words rhyme?", For example. And we did that with a group of healthy men and healthy women, and we could see what parts of their brain were activated as they were trying to do this task. And when we examined the data, we found very significant differences between males and females. Males activated the left side of the brain, whereas females activated the left but the right as well. And what was even more interesting was that there was no difference in how accurate the males or females were or how quickly they could do the task. And I think this points out a very, very important finding -- that is that we're not talking about who's better and who's worse, because that's a silly question. What we're talking about is that it's possible for males and females to go about doing the task by different routes, but coming to the same result. So I think that's really important, and that gets back to what you asked me initially. I began by talking about the... what happens when a male versus a female has a stroke. So now we know, because males only have representation on the left -- if they have a stroke on the left side of the brain, that is going to have a profound impact on their language. But if a woman, a female has this, she still has the right side to call upon.
GWEN IFILL: Do the findings in this report more profoundly affect women's health or men's health or everyone's potentially?
SALLY SHAYWITZ: Well, I think our sense is, if we can understand... For example, women seem to be protected against heart disease until they are post menopausal; but if we can understand, for example, those protective factors better, we might have a clue to understanding why males tend to have heart symptoms earlier. So our belief, and I think it's a correct one, is by understanding sex differences that are so important, these will provide clues to better health for everyone, males and females.
GWEN IFILL: How do you sell this now in terms of practical implications, practical research, practical difference in the outcome?
SALLY SHAYWITZ: Well, I think what we need to do is, one, have an awareness of the importance of sex, as what we would say a biologic variable, so that studies can be designed to examine this; and an awareness, for example, among physicians; that it matters if you're prescribing a particular drug to a male or female. And, in fact, several drugs have been pulled off the market because they cause very serious arrhythmias in females. So this isn't just a theoretic issue. There are already known, profound sex differences that have major medical implications, but the more we can understand at the basic and cellular level that affect all cells, the better we can plan treatments and diagnose individuals and hopefully prevent disease.
GWEN IFILL: Several steps beyond Mars and Venus.
SALLY SHAYWITZ: I think so.
GWEN IFILL: Dr. Sally Shaywitz, thank you very much for joining us.
SALLY SHAYWITZ: What a pleasure. Thank you.