Gender-affirming hormone therapy effect on cortisol levels in trans males and trans females.

PURPOSE: Previous studies have shown differences in baseline and stimulated cortisol levels between men and women. Whether this difference is secondary to sex hormones or to other factors, such as genetic or epigenetic changes, is unknown. We investigated the effect of gender-affirming hormone treatment (GAHT) on the hypothalamo-pituitary-adrenal axis of transgender subjects in an effort to throw light on this question. METHODS: Ten transgender males (TM) and eight transgender females (TF) underwent a low-dose (1 µg) adrenocorticotropic hormone (ACTH) stimulation test before and 6 months after GAHT initiation. Serum total, free and salivary cortisol (SC) levels were measured at baseline and at 20, 30 and 40 min. RESULTS: For the TM, all three levels were significantly lower at several time points after ACTH injection compared to pretreatment levels following 6 months of treatment (p < .05). Likewise, the overall SC response as calculated by the area under the curve was significantly lower (p = .0053). For the TF, the basal total cortisol (TC) level increased after 6 months of treatment (p < .01) while ACTH-stimulated SC levels decreased significantly. The basal ACTH levels were significantly lower following hormonal therapy (p < .001). CONCLUSION: Stimulated salivary cortisol levels decreased significantly after 6 months of GAHT in both male and female transgender subjects, possibly reflecting a decreased state of anxiety associated with treatment initiation. Additionally, basal and stimulated serum TC levels increased after hormonal treatment in the TF, probably secondary to the effect of oestrogen on cortisol-binding globulin.

Sublingual Estradiol Offers No Apparent Advantage Over Combined Oral Estradiol and Cyproterone Acetate for Gender-Affirming Hormone Therapy of Treatment-Naive Trans Women: Results of a Prospective Pilot Study.

Purpose: Chronic gender-affirming hormone therapy (GAHT) with sublingual estradiol (SLE) has not been studied. We aimed to compare GAHT with SLE only, to combined oral (CO) estradiol and cyproterone acetate, in treatment-naive trans women. Methods: Twenty-two trans women enrolled into either the CO arm or the SLE-only arm (0.5 mg four times daily) in this 6-month prospective study. Anthropometric and laboratory variables were collected at baseline and 3 and 6 months. At the study beginning and end, body composition was measured by dual-energy X-ray absorptiometry and bioelectrical impedance, and gender dysphoria, sexual desire, and function were assessed by validated questionnaires. Results: Subjects in the SLE were older, 26.3±5.8 years versus 20.1±2.3 years, p=0.006. All anthropometric, body composition, and laboratory variables were identical at baseline. Although dysphoria appeared greater, and sexual function lower at baseline in the CO group, this canceled out after age adjustment. Both treatments induced similar biochemical and hormonal changes. Creatinine, hemoglobin and cholesterol decreased significantly, while testosterone was suppressed to the same level in both groups: 3.22 [1.47-5.0] nmol/L in the SLE group and 2.41 [0.55-8.5] nmol/L in the CO, p=0.65. Significant changes in body composition toward a more feminine body were noted in both groups. Dysphoria did not significantly improve in either group, while sexual desire and function decreased at six months in both, p<0.001. Conclusions: Both treatments achieved similar clinical changes. At this stage, SLE, which repeatedly induces alarming excursions of serum estradiol throughout the day, appears to offer no advantage over the CO approach.