To promote cardiac health for women, the AHA started the Red Dress campaign. Source: CardioTabs

Women remain a significant minority in cardiovascular randomized controlled trials funded by the National Heart, Lung and Blood Institute (NHLBI), according to Cleveland Clinic researchers.

The results of “Enrollment of Women in NHLBI Funded Cardiovascular Randomized Controlled Trials Fail to Meet Current Federal Mandates for Equal Inclusion” were presented at the American Heart Association Scientific Sessions held last week in Orlando, Fla.

Senior authors, Esther Kim, MD, Venu Menon, MD, and colleagues at the Cleveland Clinic examined the National Institutes of Health’s (NIH) database of clinical trials for studies funded by the NHLBI with outcomes of stroke, heart attack or death. The studies were published between 1997 and 2006.

Of the 982 NHLBI-funded cardiovascular studies examined, 141 were phase III or IV randomized controlled trials in adults, and 53 had outcomes of interest. The study spanned 19 trials: nine acute, eight high risk, eight coronary artery disease, three congestive heart failure, seven electrophysiology trials and one hypertension trial. The researchers reported no significant increase in the enrollment of women between 1997 and 2006 (mean of 27 percent).

“Despite federal mandates, NIH policies, and ongoing NIH scrutiny, enrollment of women remains inadequate in NIH-sponsored, phase III-IV, cardiovascular randomized, controlled trials,” Kim said. “In addition, there has been little change in the proportion of women enrolled in these trials over the past decade.”

The under-representation of female participants was recognized in the 1990s, and resulted in NIH mandates for the inclusion of women in clinical research. Cleveland Clinic researchers evaluated the impact of the guidelines on federally funded cardiovascular randomized controlled trials.

Kim suggested that educational efforts at the patient level, study site and investigator level are needed to increase participation of women. Additional research into “why so few women participate in clinical trials is also warranted,” she added.