Analysis: Women, Older Adults Underrepresented in Cholesterol Drug Trials

Women and older adults are underrepresented in clinical trials evaluating cholesterol medications, according to a new study published in JAMA Network Open.

Despite heart disease being the leading cause of death among women, and older adults being at higher risk than younger individuals, many randomized clinical trials testing medications to lower cholesterol do not include enough participants from these patient populations.

The study included a systematic review of 60 trials involving 485,509 participants that were conducted between 1990 and 2018. The investigators sought to examine patterns of representation of women and older adults in lipid-lowering randomized clinical trials.

Overall, the results showed an increase in the number of women participants from approximately 20% in the early 1990s to approximately 33% in more recent trials; however, many trials included only women who were past menopause or who were unable to have children. These trials particularly excluded women who were pregnant or breastfeeding. Women were underrepresented compared with their disease burden in lipid randomized clinical trials of diabetes, heart failure, stable coronary heart disease, and acute coronary syndrome.

Overall representation of older participants was 46.7%, which increased from 31.6% in the period 1995 to 1998 to 46.2% in the period 2015 to 2018, according to the data.

A total of 53% and 36.6% trials reported outcomes according to sex and older participants, respectively, which did not improve over time.

According to the study authors, although enrollment of these individuals increased over time, women and older adults remained consistently underrepresented. The findings limit the evidence base for efficacy and safety in these subgroups, they concluded.

“We want to ensure that the types of patients who will be using these drugs are the ones included in the clinical trials, so that we can determine if these medications are safe and effective for the people who are prescribed them,” senior author Erin Michos, MD, MHS, associate professor of medicine at the Johns Hopkins University School of Medicine, said in a press release. “Although we did see an improvement over the years in representation of women and older adults, that progress was rather modest. Clearly more still needs to be done to shift the balance to represent our patient demographics.”

References:

1. Khan SU, Khan MZ, Subramanian CR, et al. Participation of women and older participants in randomized clinical trials of lipid-lowering therapies: a systematic review. JAMA Network Open. 2020. doi:10.1001/jamanetworkopen.2020.5202

2. Research Story Tip: Still Not Enough Women and Older Adults in Cholesterol Drug Trials, Study Finds. News Release. Johns Hopkins Medicine; May 21, 2020. Accessed May 22, 2020. https://www.hopkinsmedicine.org/news/newsroom/news-releases/research-story-tip-still-not-enough-women-and-older-adults-in-cholesterol-drug-trials-study-finds