Gender-affirming hormone treatment causes changes in gender phenotype in a 12-lead electrocardiogram.

BACKGROUND

Men and women have specific patterns in an electrocardiogram (ECG) differentiated by J-point elevation and ST-segment angle. Although gender-affirming hormone treatment is one of the treatments for gender dysphoria, its influence on an ECG has not been clarified yet.

OBJECTIVE

The purpose of this study was to investigate ECG changes induced by gender-affirming hormone treatment.

METHODS

The study population consisted of 29 transgender males and 8 transgender females and 37 age- and sex-matched cisgender females and males. Male pattern was defined as J-point elevation > 0.1 mV and ST-segment angle > 20° in precordial leads.

RESULTS

In the comparison between 29 transgender males and cisgender females, the prevalence of the male pattern (89.7% vs 6.9%; P < .001), prevalence of the early repolarization pattern (51.7% vs 17.2%; P = .01), J-point elevation (leads V-V), T-wave amplitudes (leads V-V), QRS amplitudes (leads II, III, V-V), and P-wave amplitudes (leads V-V) were significantly higher in transgender males. The prevalence of the male pattern was lower in transgender females than in cisgender males (25.0% vs 87.5%; P = .04). In the analysis of transgender males for whom ECGs were available before and after gender-affirming hormone treatment (n = 13), J-point elevation and T-wave amplitudes significantly increased after gender-affirming hormone treatment, leading to a higher prevalence of the male pattern (23.1% vs 92.3%; P < .001). The prevalence of the early repolarization pattern and QRS amplitudes also significantly increased after the treatment, but the augmentation of P-wave amplitudes was modest.

CONCLUSION

Gender-affirming hormone treatment for gender dysphoria is accompanied by a change in ECG phenotype toward affirming gender, in which change in androgen level may be involved.