Improving women’s cardiovascular health

Clinical research based on biological sex: A matter of equity

Date published: 2022-03-24 12:00:00 PM

Magnification of men’s and women’s valve histology (microscopic examination of the structures of tissues).

Photo: J Am Heart Assoc. 2020;9:e015610

Although women are five times more likely to die of a cardiovascular disease than of breast cancer, they are underdiagnosed, primarily because they are underrepresented as research subjects in heart health studies. Marie-Annick Clavel, Canada Research Chair in Women’s Cardiac Valvular Health at Université Laval, is working to close this gap by studying cardiac valvular diseases in women. Her research team hopes to improve the level of care offered to women with valvular diseases and increase their chances of survival.

According to Marie-Annick Clavel, “there is an old myth that estrogens protect women from cardiovascular diseases. But there are as many women as men with cardiac valvular diseases. The problem is that women are diagnosed less frequently and, therefore, treated less often. This results in more women dying than men.”

Gender parity, including in clinical studies

Valvular diseases—dysfunctions that cause poorer heart blood circulation—have been primarily studied in men, on the assumption that the appearance, progress and risks related to these diseases are similar in men and women. Men represent between 80% and 90% of participants in clinical studies. Since diagnostic methods have been developed mainly by studying men, women are five times less likely to be diagnosed correctly.

Canada Research Chair Marie-Annick Clavel and her lab team promoting the February 2022 edition of Wear Red Canada, an annual event to raise awareness about women’s heart health.

Photo: Marie-Annick Clavel

The same applies to treatment, which has also been developed with a focus on men. However, the biological differences between the sexes (for example, the heart and arteries of women are smaller) have an impact on the progression of valvular diseases. By studying aortic valvular stenosis (the narrowing of the cardiac valve between the heart and the aorta), Marie-Annick Clavel and her team have discovered that, in women, this abnormality is mainly caused by fibrosis and not by calcification, while the opposite applies to men. As a result, women should be treated differently.   

The researcher adds that “it is important to conduct clinical studies that specifically consider the biological sex of patients. By differentiating data based on sex, we increase the accuracy and reliability of our findings. If we do not do this, the data will be less precise, which will have an impact not only on women’s health, but also on that of men.”

Providing doctors with the right tools to recognize and treat cardiovascular diseases

In addition to contributing to bridging the gap between the sexes in cardiovascular research, Clavel’s findings have been incorporated into practice guides for the treatment of patients with valvular diseases currently in use by cardiologists and heart surgeons in Canada, the United States and Europe.

Thanks to these guides, doctors are better equipped to help their ever-growing number of patients. Valvular diseases are the third most frequent type of cardiovascular disease in Canada and they are often the least correctly diagnosed, especially in women. In Canada, 2.5% of the population is affected (approximately 80,000 people) and more than 5% of Canadians are expected to have cardiovascular disease in 2050 as a result of an aging population.

Interest in Clavel’s research goes beyond Canada’s borders, as cardiovascular diseases continue to afflict the world. Researchers from four continents—the Americas, Europe, Africa and Asia—are contributing to her research by providing data divided by sex and gender.

Of this collaboration, Clavel says, “We are lucky to rely on contributors from different specializations—doctors, pharmacists, nurses, engineers—to get a full picture of valvular diseases. That way, we can provide both women and men with tailored diagnoses, treatments and follow-ups.”  

Testing a promising molecule

Marie-Annick Clavel has also been busy proactively combating other valvular diseases by leading an international study on a new indication for an existing drug that could target the most frequent cause of aortic valvular stenosis in women. The goal is to slow the disease’s progression, stop it and, with a bit of luck, reverse it. If the new indication proves to be promising, women could defer heart surgeries for four or five years, or even avoid them completely.

The drug is currently being studied in Denmark and will soon be also in Scotland. Until its potential market entry, Clavel offers a good-natured piece of advice: “As women can show different symptoms than men, I would like to remind women of the importance of seeking information, listening to their own bodies and, most importantly, taking care of themselves.”

For more information

You can find the specifics of Marie-Annick Clavel’s research on the Canada Research Chair in Women’s Cardiac Valvular Health website and on her lab’s website (French only). Her lab belongs to the Quebec Heart and Lung Institute’s  Research Group on Cardiac Valvular Diseases. You can also follow her on Twitter to learn about her research.