Medical research still short on inclusion of women

It seems obvious: Women make up half the population, so they should be the subject of half of medical research. But until about 20 years ago, most scientists assumed women were just like men, with a few different body parts.

Now researchers understand that gender affects everything from how people respond to medicines to their likelihood of getting sick. Every cell bears the mark of the person's gender, and diseases like Alzheimer's, multiple sclerosis and depression are more likely to strike women, while Parkinson's, autism and schizophrenia are more common in men.

Still, research and medical practice often ignore sex. Even lab mice remain mostly male, as do the cells studied in labs around the world.

The National Institutes of Health announced new policies recently designed to ensure that the studies it funds take gender into account.

"By considering sex as a fundamental variable in research from the very beginning, we can make sure men and women get the full benefit of research," said Janine Clayton director of the U.S. National Institutes of Health Office of Research on Women's Health.

In an article in the journal Nature on May 14, Clayton and NIH director Francis Collins, said they will roll out new policies beginning in October, requiring federally funded research to take gender into account. The sex of research animals and cells will be considered when reviewing grant requests, the two said, and the NIH will encourage journals to publish results related to gender.

These research gaps can have profound affects on treatment, said Paula Johnson, executive director of the Mary Connors Center for Women's Health and Gender Biology at Brigham and Women's Hospital in Boston, who recently launched a campaign to bring attention to the issue of gender in research.

"Many women receive recommendations from their doctors – for prevention strategies, diagnostic tests and medical treatments – that are based on research that has not adequately included women or reported results on women," said Johnson, also an expert in women's heart disease at Harvard Medical School.

In heart disease, for example, women have different symptoms and even scans of their arteries appear different than men's, but most doctors were trained only to look for heart disease in men, she said.

"You have to be thinking and have knowledge that these sex differences occur and that knowledge is not routinely applied in clinical care," Johnson said at a recent conference, Charting the Course: A National Policy Summit on the Future of Women's Health, held in Boston.

At the conference, Sen. Elizabeth Warren, D.-Mass., said her own mother died of heart disease that went unrecognized because her caregivers thought only men got the illness.

"I'm here today in part to honor my mother, and in part because I have two granddaughters, and that will not be the world my granddaughters grow up in," Warren told the group.