Testosterone treatment and MMPI-2 improvement in transgender men: a prospective controlled study.

OBJECTIVE Most transgender men desire to receive testosterone treatment in order to masculinize their bodies. In this study, we aimed to investigate the short-term effects of testosterone treatment on psychological functioning in transgender men. This is the 1st controlled prospective follow-up study to examine such effects. METHOD We examined a sample of transgender men (n = 48) and nontransgender male (n = 53) and female (n = 62) matched controls (mean age = 26.6 years; 74% White). We asked participants to complete the Minnesota Multiphasic Personality Inventory (2nd ed., or MMPI-2; Butcher, Graham, Tellegen, Dahlstrom, & Kaemmer, 2001) to assess psychological functioning at baseline and at the acute posttreatment follow-up (3 months after testosterone initiation). Regression models tested (a) Gender × Time interaction effects comparing divergent mean response profiles across measurements by gender identity; (b) changes in psychological functioning scores for acute postintervention measurements, adjusting for baseline measures, comparing transgender men with their matched nontransgender male and female controls and adjusting for baseline scores; and (c) changes in meeting clinical psychopathological thresholds. RESULTS Statistically significant changes in MMPI-2 scale scores were found at 3-month follow-up after initiating testosterone treatment relative to baseline for transgender men compared with female controls (female template): reductions in Hypochondria (p < .05), Depression (p < .05), Hysteria (p < .05), and Paranoia (p < .01); and increases in Masculinity-Femininity scores (p < .01). Gender × Time interaction effects were found for Hysteria (p < .05) and Paranoia (p < .01) relative to female controls (female template) and for Hypochondria (p < .05), Depression (p < .01), Hysteria (p < .01), Psychopathic Deviate (p < .05), Paranoia (p < .01), Psychasthenia (p < .01), and Schizophrenia (p < .01) compared with male controls (male template). In addition, the proportion of transgender men presenting with co-occurring psychopathology significantly decreased from baseline compared with 3-month follow-up relative to controls (p < .05). CONCLUSIONS Findings suggest that testosterone treatment resulted in increased levels of psychological functioning on multiple domains in transgender men relative to nontransgender controls. These findings differed in comparisons of transgender men with female controls using the female template and with male controls using the male template. No iatrogenic effects of testosterone were found. These findings suggest a direct positive effect of 3 months of testosterone treatment on psychological functioning in transgender men.