Cardiometabolic diseases in transgender populations.

The number of people seeking gender-affirming medical care and gender-affirming hormone therapy (GAHT) is increasing. As sex steroids shape cardiometabolic physiology, GAHT is expected to meaningfully alter cardiometabolic risk. The aim of this review was to systematically determine and narratively synthesize evidence on the cardiometabolic effects of GAHT and identify clinically relevant knowledge gaps. We searched PubMed for English-language primary human studies published through November 26, 2025. Of 346 screened records, 96 unique original investigations were included. Most studies had less than 3 years of follow-up, the longest being 20 years in one electronic health record-based study. In transgender women, BMI was often reported as stable with higher fat and lower lean mass compared to baseline; insulin resistance tended to increase while fasting glucose and HbA1c were usually longitudinally stable. Lipid changes often showed reductions in total and low-density lipoprotein cholesterol as well as triglyceride levels. Blood pressure generally remained stable or decreased. In transgender women, VTE incidence was higher than in both cisgender women and men, whereas stroke and MI incidence was higher primarily in comparison with cisgender women. In transgender men, BMI was increased or stable and lean mass increased with variable fat mass changes and some long-term increases in visceral and liver fat. Glucose usually remained stable while insulin resistance findings were mixed. Lipid profiles commonly shifted toward lower high-density lipoprotein cholesterol and higher low-density lipoprotein cholesterol and triglycerides. Blood pressure findings were mixed with some cohorts showing an increase. In transgender men, MI incidence was higher than in cisgender women but generally not higher than in cisgender men; evidence for other cardiovascular outcomes was limited and inconsistent. Overall, evidence on systemic inflammation, renal and hepatic outcomes is sparse. In conclusion, GAHT is associated with quantifiable cardiometabolic changes, but magnitude and clinical relevance vary by regimen, population, baseline risk and study follow-up duration. Heterogeneous regimens, study methods, and confounding contribute to mixed findings. Major gaps persist with limited long-term prospective data, sparse mechanistic insights, underrepresentation of adolescents and non-European ancestry populations, and insufficient information on cardiometabolic outcomes with ageing.