Observational Study on the Short- and Long-term Effects of Cross-sex-hormone Treatment on Metabolism and Psychopathology in Transsexuals Patients.

Gender identity disorders (also known as transsexualism) is defined as a condition in which a person with apparently normal somatic sexual differentiation is convinced that he or she is actually a member of the other sex. Most patients therefore undergo so called cross-sex hormone treatment. Treatment protocols follow international consensus statements but vary considerably between different centres and countries since no prospective and controlled trials are available on this subject and recommendations are mainly based on retrospective data analysis and experience of the individual centres. Applying high doses of testosterone to biological females and vice versa high doses of estradiol to biological males definitely impacts myriads of body functions, from which it has to be assumed that only a minority has already been elucidated so far. Especially in male-to-female-transsexuals there seems to be an increased risk for the development of mood disorders and cardiometabolic comorbidities. In this multi-center observational study we want to investigate, if there is any difference with regard to these outcomes, according to the varying standards of cross-sex hormone treatment between the different centers. Different outcome measures described below will be assessed each time during routine visits at the different centers.