Endocrine Abstracts

Introduction: In gender affirming therapy of the transgender male, increasing doses of testosterone are administered and as the androgen dose increases, various biochemical parameters such as haematocrit, creatinine and PSA increase. It is not known whether any parameters have advantages in monitoring this androgenisation. Our study evaluates the correlation between the increase in androstanediol glucuronide, testosterone, free testosterone and free androgen index (FAI) with the aforementioned biochemical parameters in a cohort of 20 trans men who started gender affirming therapy.

Material and Methods: Samples were obtained from 20 transgender men at the initiation of testosterone cypionate therapy and after each 3-monthly dose increment of 25 mgrs, up to a maximum of 250 mgsr during one year of treatment. Testosterone, free testosterone, DHEAS, on the Snibe Maglumi platform, PSA and creatinine on the Siemens atellica autoanalyser and haematocrit on the Beckman Coulter DXH900 analyser were analysed. The 3α androstanediol glucuronide (3αAG) was analysed by ELISA (DRG). Correlations were performed with Sperman’s test between the different parameters using SPSS 25.0 statistical software.

Results: For haematocrit all androgens analysed were significantly correlated, however there are differences in the Rho (ρ) between each pair. FAI has the best correlation:ρFAI= 0.568/P<0.001. The correlation coefficients of the other androgens were:ρtestosterone= 0.556,ρfTestosterone= 0.545,ρ3αAG = 0.535,ρDHEAS= 0.532 with a P<0.001 for all of them. Serum creatinine levels correlate only with androstenedioneρandrostenedione=0.373/P=0.002, and DHEASρDHEAS=0.297/P=0.010. This correlation decreases in oophorectomised patients. For PSA, as for haematocrit, all androgens were significant. The best correlation was for testosteroneρTestosterone= 0.347/P=0.003 followed by free testosterone:ρfTestosterone= 0.274/P=0.021. The other androgens showed no significant correlation, although FAI (P=0.088) and androstenedione (P=0.078) showed a clear trend towards a significant correlation.

Conclusions: The different androgens have different correlation coefficients depending on the marker used. FAI obtained the best result with haematocrit, making it the parameter of choice when assessing the relationship between a given dose and its increase. Significance was obtained for creatinine with androstenedione and DHEAS and for PSA with testosterone and free testosterone. The different androgens are associated with different biochemical parameters and should therefore be assessed individually when evaluating androgenisation in these subjects.