# Association between serum testosterone and measures of cardiovascular health among transgender individuals using gender-affirming testosterone therapy: a cross-sectional study

## TL;DR

This study found no significant link between testosterone levels and cardiovascular health in transgender individuals on testosterone therapy, though more research is needed.

## Contribution

The study is the first to explore the relationship between serum testosterone and validated cardiovascular health measures in transgender individuals on gender-affirming testosterone therapy.

## Key findings

- Total and free serum testosterone were not significantly associated with systolic blood pressure or arterial stiffness measures.
- Free testosterone showed a positive association with aortic augmentation index, but this did not reach significance for total testosterone.
- The small sample size limits the generalizability of the findings.

## Abstract

Gender-affirming testosterone therapy (GATT) use may be associated with increased systolic blood pressure (SBP). The association between serum testosterone and cardiovascular health in individuals using GATT is unknown. The objective of this study was to estimate the association between serum testosterone and validated measures of cardiovascular health, including SBP and arterial stiffness, in persons assigned female sex at birth using GATT.

Healthy participants assigned female sex at birth on a stable GATT regimen for ≥ 4 months were recruited to this community-partnered exploratory cross-sectional study. Exposures of interest were total and free serum testosterone concentration. As our primary outcome, SBP was measured by an automated sphygmomanometer, and carotid-radial pulse wave velocity (PWVcr) and aortic augmentation index (AIx) were used to measure arterial stiffness via applanation tonometry.

Participants (n = 18, median age 28 years, range: 18, 50) who predominantly self-identified as white (94%) and had been using GATT for a median of 48 months (range: 5, 84) were studied. Resting SBP, PWVcr, and AIx were 113 mmHg (range: 102, 129), 7 m/s (range: 4, 9), and 9% (range: − 10, 23), respectively. Total and free serum testosterone were not significantly associated with SBP or PWVcr. Free, but not total, serum testosterone was positively associated with AIx (p = 0.03). Sensitivity analyses did not modify any results.

In healthy transgender individuals, serum testosterone concentrations may not be associated with measures of cardiovascular health. However, these results need to be interpreted with caution given the limited sample size.

The online version contains supplementary material available at 10.1186/s13293-025-00726-3.

We assessed the association between serum testosterone concentration and markers of cardiovascular health in transgender individuals using GATT.We did not identify an association between serum total testosterone concentrations and cardiovascular health markers in healthy transgender individuals treated with GATT.In healthy transgender individuals treated with GATT, serum testosterone concentrations may not be associated with measures of cardiovascular health.Although longitudinal studies are required, these results may inform shared decision-making between individuals using GATT and their healthcare providers.

We assessed the association between serum testosterone concentration and markers of cardiovascular health in transgender individuals using GATT.

We did not identify an association between serum total testosterone concentrations and cardiovascular health markers in healthy transgender individuals treated with GATT.

In healthy transgender individuals treated with GATT, serum testosterone concentrations may not be associated with measures of cardiovascular health.

Although longitudinal studies are required, these results may inform shared decision-making between individuals using GATT and their healthcare providers.

The online version contains supplementary material available at 10.1186/s13293-025-00726-3.

Testosterone therapy is an important part of gender-affirming care for many transgender individuals. However, concerns exist about how this therapy might affect heart and blood vessel health. This study aimed to explore whether testosterone levels in the blood are linked to these measures of cardiovascular health. We studied 18 adults who were assigned female at birth and had been on stable testosterone therapy for at least four months. We measured their blood pressure and used specialized tools to assess arterial stiffness, a marker of blood vessel health. Our results demonstrated that testosterone levels were not significantly linked to blood pressure. Overall, in healthy transgender individuals treated with testosterone, serum testosterone measurements may not be linked to blood pressure or blood vessel health. However, further research is required to confirm this. This research highlights the importance of understanding how testosterone therapy affects the heart and blood vessels to ensure the best possible care for those undergoing gender-affirming treatments.

The online version contains supplementary material available at 10.1186/s13293-025-00726-3.