MedicalResearch.com Interview with:
Michael Goodman, MD, MPH
Professor of Epidemiology
Director, MD/MPH program
Emory University School of Public Health
Atlanta, GA 30322
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: There is a concern that hormone therapy may be associated with higher risk of certain cardiovascular problems such as heart attacks, stroke and formation of blood clots (“venous thromboembolism”).
To study this concern we examined data on 4,960 transgender and gender non-conforming people enrolled in Kaiser Permanente health systems in Georgia, Northern California, and Southern California. They were matched to 48,686 cisgender men and 48,775 cisgender women. Below are the main findings
- Rates of venous thromboembolism in all transwomen were approximately twice as high as the rates among cisgender men or cisgender women. The data for stroke and myocardial infarction demonstrated little difference between transwomen and cisgender men, but 80% to 90% higher rates among transwomen compared to cisgender women.
- When the analyses focused specifically on transwomen who started therapy with female hormone estrogen at Kaiser Permanente, the incidence of both venous thromboembolism and stroke was more clearly elevated relative to either reference group. There was evidence that incidence of both of these conditions among transwomen was particularly increased two to six years after estrogen initiation. By contrast, the association between estrogen therapy and myocardial infarction was less evident due to relatively few observed events.
- Transmen did not appear to have significantly higher rates of venous thromboembolism, ischemic stroke, or myocardial infarction than their non-transgender counterparts, but this group was rather young and included a relatively small proportion of participants who initiated their hormone therapy during the study.