Dose-response analysis of testosterone replacement therapy in patients with female to male gender identity disorder

Abstract

Gender identity disorder (GID) is a condition where an individual experiences significant gender dysphoria or discontent due to the divergence between their biological sex and their actually perceived sex. The concept of GID was introduced in the 20 th century [1], and the affected patients usually indicate an apparently normal somatic sexual differentiation and hope to live as the member of the opposite gender to their innate one. The number of patients diagnosed with the condition has been increasing in the past decade. Currently, a broad approach toward to treatment of GID is conducted from various aspects of law, sociology, psychol- Abstract. Gender identity disorder (GID) is a conflict between a person's actual physical gender and the one they identify him or herself with. Testosterone is the key agent in the medical treatment of female to male GID patients. We conducted a dose-response analysis of testosterone replacement therapy (TRT) in 138 patients to determine the onset of the therapeutic effects. The TRT consisted of intramuscular injection of testosterone enanthate and patients were divided into three groups; 250 mg every two weeks, 250 mg every three weeks and 125 mg every two weeks. The onset of deepening of voice, increase in facial hair and cessation of menses was evaluated in each group. At one month after the start of TRT, the onset of these physical changes was more prevalent in the group receiving the higher dose of testosterone, and there were dosedependent effects observed between the three treatment groups. On the other hand, at six months after the start of TRT, most of the patients had achieved treatment responses and there were no dose-dependent effects with regard to the percentage of patients with therapeutic effects. No significant side effects were observed in any of the treatment groups. We demonstrated that the early onset of the treatment effects of TRT is dose-dependent, but within six months of starting TRT, all three doses were highly effective. Current study provides useful information to determine the initial dose of TRT and to suggest possible changes that should be made in the continuous dosage for long term TRT.Key words: Gender identity disorder, Testosterone, Female to male, Dose response analysis, Estradiol ogy and medicine to effectively manage the disorder.The aim of the treatment for GID patients is to provide relief from the dichotomy between body habitus and sex identity by the induction of desired mental changes and maintenance of an acceptable physical state of the opposite sex. With regard to the history of the medical approach towards GID, surgical intervention was first conducted in 1907, and hormone therapy using testosterone replacement in female to male GID was started from 1935 after the discovery of testosterone [2]. Currently, the treatment for GID consists of psychotherapy, hormone replacement therapy and sex reassignment surgery. The therapeutic strategy is often determined, and therapies are started, by incorporating the patient's preferences or base...

Testosterone replacement elevates the serum uric acid levels in patients with female to male gender identity disorder

“…We also demonstrated that the onset of hyperuricemia was more prevalent in the high-dose group. As shown in previous studies, maximal serum testosterone levels are achieved immediately after testosterone injection, and early testosterone levels are TRT dose-dependent [6,17]. Therefore, the higher serum testosterone concentration induced by a higher dose of TRT causes dose-dependent serum UA upregulation.…”

“…The assays of serum testosterone and estradiol were performed using an electrochemiluminescence immunoassay (ECLIA), as previously described [6]. The serum testosterone level was measured as the total testosterone level; the standard value ranged from 131~871 ng/dL in males and 11~47 ng/ dL in females.…”

“…The most frequently used regimens include 100~250 mg of testosterone enanthate administered via intramuscular injection every two to three weeks [3,4]. We previously reported the physical therapeutic effects of three TRT doses (125 mg every two weeks, 250 mg every three weeks and 250 mg every two weeks) [6]. We experienced that, when TRT is initiated, testosterone immediately affects the systemic metabolism in female to male GID patients.…”

“…Patients with female to male GID undergo a standard psychiatric evaluation to rule out major functional psychiatric disorders, such as schizophrenia, mood disorders and neurosis. The GID clinic provides genetic testing, diagnosis, counseling, hormonal therapy and plastic surgery, and all aspects of this study were approved by the Ethics Committee of Okayama University Hospital [6,14,15]. Between January 2002 and May 2011, a total of 160 Japanese patients were diagnosed with female to male GID and treated with testosterone replacement therapy (TRT) in the GID clinic.…”

“…GID patients to promote male sex characteristics, such as a beard, body hair, increased muscle mass and a deeper voice [2][3][4][5][6]. However, testosterone administration also leads to side effects, including water and sodium retention, hypertension, increased erythropoiesis, an increased low-density lipoprotein (LDL) level, a decreased high-density lipoprotein (HDL) level, elevation of liver enzymes, induction of obesity and acne and emotional and psychiatric problems [2][3][4][5][6].…”