Endocrine Abstracts

Introduction: Testosterone-based gender-affirming hormone therapy (GAHT) may have negative consequences on cardiovascular risk, with reported increased blood pressure, decreased HDL-cholesterol, and weight gain. Still, data on cardiometabolic changes in transgender men on GAHT remain controversial. Testosterone-based GAHT also modifies body composition and lean muscle mass, but the degree to which affects serum creatinine and other measures of kidney function is still not clear.

Objectives: To characterize the change in cardiometabolic risk factors (blood pressure, weight, lipid profile) and serum creatinine in transgender people initiating masculinizing GAHT.

Methods: Single-centre retrospective study, including a cohort of 60 transgender males, with follow-up between 2015-2022. Data collection was performed before and after one year of initiating GAHT and included levels of total-cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, and serum creatinine; blood pressure and weight. Estimated glomerular filtration rate (eGFR) was calculated based on CKD-EPI equation for cisgender. We excluded people: with previous renal failure or dyslipidemia; under therapies with influence on lipid profile/renal function; submitted to ovariectomy.

Results: Transgender males average age was 22.5 ±6.7 years. Prescribed GAHT consisted of testosterone enanthate/cypionate, monthly average dose 290 ±60mg. After 12 months of GAHT, there were no significant changes on weight or blood pressure. Regarding lipid profile, there was a decrease in HDL-cholesterol (-7.6mg/dL, IC 95% [-13.5;-1.7]), increase in triglycerides (+12.5mg/dL, IC 95% [0.2;24.9]), and increase in LDL-cholesterol (+14.1mg/dL, IC 95% [4.8;23.5]). We also found an increase in serum creatinine (+0.110 mg/dL, IC 95% [0.078;0.142]) and a reduction in eGFR (-16.0 ml/min/1.73m², IC 95% [-20.0;-12.0]). In a univariate regression model adjusted for testosterone dose and weight, we found significant changes in HDL-cholesterol (-7.8 mg/dL, P=0.027, r=0.153) and serum creatinine (+0.101 mg/dL, P<0.001, r=0.307).

Conclusion: We observed an unfavorable trend in lipid profile in transgender males after one year of GAHT. Healthcare professionals should monitor and discuss lifestyle interventions and pharmacological therapy with patients who are at risk of developing cardiovascular disease. Serum creatinine also changed, resulting in a decreased eGFR. However, this presumably may reflect the corresponding increase in muscle mass, rather than a true change in GFR. Our results raise the question of how to estimate GFR based on equations in transgender people, as one of the variables is gender, and serum creatinine is affected by GAHT.