Medical devicemakers are required to include women in studies they submit for approval. But research published in Circulation: Cardiovascular Quality and Outcomes shows only a few studies include enough women or analyze how the devices work specifically in them.
"Women and men differ in their size, bleeding tendencies and other factors that are directly relevant to how the devices will work," explains Rita Redberg, senior author of the study and professor of medicine and director of Women's Cardiovascular Services at the University of California, San Francisco. "It is likely that the benefits and risks of devices are different in women. Despite the directive to find out, it isn't happening."
The researchers reviewed 123 studies contained in the pre-market approval applications for 78 high-risk cardiovascular devices that gained FDA approval between 2000 and 2007. And in 28 percent of the studies, FDA summaries of the evidence didn't report the gender of study participants. In those that did, men made up an average of 67 percent.
The investigators also found that the required gender-bias statement was present in only 41 percent of the studies. Of studies that included the statement, 94 percent discussed examining their results by sex, and 26 percent reported differences in device safety or effectiveness between men and women.
In approved applications, the reviewers found instances in which researchers used inaccurate grounds to exclude women. And in some cases, the proportion of women with a heart condition was understated. In others, applicants declared their gender breakdown to be equivalent to previous studies without acknowledging that the previous studies included a disproportionately low number of women.
"Half the people that get heart disease are still women," Redberg told Reuters. "Men are on average 10 years younger than women when they get heart disease, but we catch up."
When asked about the study results, an FDA representative said the agency is working to correct these shortcomings, as HealthDay reports. "The findings reported in this study are not new," said spokeswoman Karen Riley. "FDA is aware of the under-representation of women in clinical trials," she added.