Category: Other - Transgender Medicine
The primary aim is to determine the relationship between age and BMI and the testosterone dose required to maintain a normal adult male serum testosterone level in transgender men. The secondary aim is to assess the correlation between testosterone dose and time to development of facial hair, deepening of voice, cessation of menses, and clitoromegaly.
Methods : Within our office, 40 transgender men were treated from July 1, 2014 to July 1, 2018 and were included in the retrospective analysis. Univariate and multivariate mixed model analyses were performed to determine the relationship between testosterone dose, age, and BMI. Cox-regression was performed to determine the relationship between time to development of each physical attribute, testosterone dose, and route of administration.
Of the 40 patients included in the analysis, 22 patients were initiated on testosterone therapy and 18 patients were already on testosterone therapy at the time of the first visit. Among all patients, there was no association between testosterone dose and BMI. However, a negative correlation was found between testosterone dose and age, with or without adjustment for BMI (p-value of 0.016 versus 0.020, respectively). Adjusted for BMI, the dose decreased by 2.0 mg for every 1 year increase in age. A subgroup analysis of the new patients again revealed a negative correlation between testosterone dose and age, with or without adjustment for BMI (p-value of 0.013 versus 0.019, respectively). Adjusted for BMI, the dose decreased by 2.5 mg for every 1 year increase in age. Subgroup analysis of the patients already on testosterone therapy did not reveal an association between testosterone dose, age, and BMI. Among the new patients, no association between time to development of each physical attribute was seen between testosterone dose or route of administration. Average follow up time was approximately 1 year.
Discussion : Our study suggests that the dose of testosterone required to maintain a therapeutic level in transgender men is not correlated with BMI but does decrease with age. However, results were not stratified by route of administration due to the small sample size. The majority of patients were able to develop each physical attribute within several months of therapy, similar to previously published studies, but no dose dependent effects were seen. The major limitation of our study is the small sample size, similar to previous studies.
The doses of testosterone used to treat transgender men may decrease with age, which has not been previously reported. Additional studies with larger cohorts are required to determine if this association holds.
Bronx, New York
Sushmitha Echt, M.D. is a second year endocrinology fellow at Northwell Health. She completed medical school at the SUNY Downstate College of Medicine in Brooklyn, NY and completed her residency in Internal Medicine at Northwell Health.
Great Neck, New York
Dr. Aren Hovie Skolnick is an attending physician in the Division of Endocrinology, Department of Medicine, at Northwell Health. He completed medical school at the New York College of Osteopathic Medicine and completed both his Internal Medicine residency and fellowship training in Endocrinology at North Shore University Hospital/Northwell Health.