Female PIs remain underrepresented in cardiovascular clinical trials despite decade of efforts

A decade of stated commitment to diversifying cardiovascular research leadership has produced almost no measurable change. When researchers at UC Berkeley examined 620 cardiovascular clinical trials funded by the National Institutes of Health or industry sponsors between 2010 and 2019, they found that only about one in five—18.4 percent—were led by women. Over those ten years, that proportion barely budged.

The imbalance cuts deeper when you look at specific trial types. Female principal investigators led just 18.9 percent of new drug trials and 9.6 percent of device trials, the categories that typically carry the most weight in shaping clinical practice. Women were more likely to direct studies in behavioral interventions, surgical procedures, or rehabilitation—work that, while important, tends to sit lower in the hierarchy of cardiovascular research. When funding source mattered, the pattern reversed: women led 28.9 percent of NIH-funded trials but only 14.7 percent of industry-sponsored ones, suggesting that government initiatives to improve representation have had some effect while pharmaceutical companies have largely moved in the opposite direction.

The research team, led by Aashna Suvarna, an undergraduate at UC Berkeley studying molecular and cellular biology, presented their findings at the American College of Cardiology's 71st Annual Scientific Session in March 2022. Suvarna noted the frustration embedded in the numbers: despite a decade of stated efforts, the needle had barely moved. "I was rather surprised that despite efforts to improve female representation in clinical trial leadership, there was barely an increase in recent years," she said. "This confirms how much more work we have to do here."

What makes this gap consequential is not abstract. Heart disease kills roughly one in five women in the United States, yet women often experience it differently than men do. A woman having a heart attack might feel neck pain, jaw discomfort, shoulder tightness, upper back strain, or abdominal pressure—symptoms that can be mistaken for something else entirely. She might experience shortness of breath, pain radiating through one or both arms, nausea, vomiting, or overwhelming fatigue. When clinical trials enroll predominantly male subjects, the resulting data may not capture these variations. Treatment guidelines built on male-centered evidence can miss what women actually need.

The research uncovered one promising correlation: female-led trials enrolled significantly more female subjects. Studies directed by women averaged 44.9 percent female enrollment compared to 37.9 percent in male-led trials—a 7 percent difference that suggests women researchers actively work to build more representative study populations. This finding points toward a practical solution: increasing female leadership in cardiovascular research could naturally improve the diversity of trial participants, which in turn would generate more accurate clinical knowledge about how heart disease presents and progresses in women.

Suvarna and her team found no standardized push from industry to improve female representation, even as government agencies like the NIH have launched initiatives aimed at the problem. In 2022, the American College of Cardiology itself introduced a program called Clinical Trials Research: Upping Your Game, designed to increase leadership roles for women, African Americans, Native Americans, and Hispanics in cardiovascular research. But without comparable commitment from pharmaceutical companies and device manufacturers—the entities that fund and shape much of the clinical trial landscape—the gap is unlikely to close on its own.

A parallel study presented at the same conference reinforced the broader pattern. Researchers examining nearly 18,500 articles published in four major cardiovascular journals over the same decade found that women represented just 20.6 percent of all authors, with virtually no growth from 2010 to 2019. Nearly half of all articles had no female author at all. The message across both studies was consistent: cardiovascular research remains a male-dominated field, and the structures supporting that dominance have proven remarkably resistant to change.