Exogenous hormone therapy for adults who are transgender: considerations for the cardiovascular system

The transgender population is a steadily increasing, heterogeneous group of individuals whose gender identity and expression differ from their birth-assigned sex. Gender-affirming hormone therapy (GAHT) is the most sought-after component of transgender care; however, the effect of exogenous sex hormones on cardiovascular health remains incompletely understood. This article reviews large cohort-based studies of transgender individuals receiving GAHT, and studies of sex hormone supplementation in cisgender populations, to identify the potential implications for cardiovascular risk factors and outcomes. Existing epidemiological evidence suggests that masculinising GAHT may have negative influences on lipid profiles in transgender men, and that transgender women undergoing feminising GAHT have an increased risk of venous thromboembolism. The effects of GAHT on blood pressure, myocardial infarction, and cerebrovascular accidents is not clear, and current observational studies are limited by diverse treatment regimes, short-term follow-up, and the inclusion of data on modifiable cardiovascular risk factors (physical activity, diet, etc.) of the cohorts.