Cardiovascular disease among transgender adults receiving hormone therapy: A narrative review

Recent reports estimate that 0.6% of adults in the United States, or approximately 1.4 million persons, identify as transgender. Despite gains in rights and media attention, the reality is that transgender persons experience health disparities, and a dearth of research and evidence-based guidelines remains regarding their specific health needs. The lack of research to characterize cardiovascular disease (CVD) and CVD risk factors in transgender populations receiving cross-sex hormone therapy (CSHT) limits appropriate primary and specialty care. As with hormone therapy in cisgender persons (that is, those whose sex assigned at birth aligns with their gender identity), existing research in transgender populations suggests that CVD risk factors are altered by CSHT. Currently, systemic hormone replacement for cisgender adults requires a nuanced discussion based on baseline risk factors and age of administration of exogenous hormones because of concern regarding an increased risk for myocardial infarction and stroke. For transgender adults, CSHT has been associated with the potential for worsening CVD risk factors (such as blood pressure elevation, insulin resistance, and lipid derangements), although these changes have not been associated with increases in morbidity or mortality in transgender men receiving CSHT. For transgender women, CSHT has known thromboembolic risk, and lower-dose transdermal estrogen formulations are preferred over high-dose oral formulations. In addition, many studies of transgender adults focus predominantly on younger persons, limiting the generalizability of CSHT in older transgender adults. The lack of randomized controlled trials comparing various routes and formulations of CSHT, as well as the paucity of prospective cohort studies, limits knowledge of any associations between CSHT and CVD.