Serum ferritin and risk of the metabolic syndrome in cross-sex hormone-treated transsexuals
Antonio Becerra Fernández1,4, Gilberto Pérez López2, Miriam Menacho3, María Jesús Lucio Pérez1, Nuria Asenjo Araque1, José Miguel Rodriguez Molina1 & José Luis Llopis Agelan5
Moderately elevated body iron stores may be associated with several components of the metabolic syndrome (MetSyn). Elevated serum ferritin levels (Fer) independently predicted incident type 2 diabetes in prospective studies in apparently healthy men and women.
Aims: To analyze the association between Fer and components of MetSyn in transsexuals before and after 2-year cross-sex treatment (CST).
Methods: Before starting the CST in 90 transsexuals (54 male-to-female (MFTs) and 36 female-to-male transsexuals (FMTs)), aged 30.6±9.0 years, we analyzed the relations between Fer and several parameters of insulin resistance (IR) (serum insulin, HOMA-IR and QUICKI) and components of MetSyn (waist circumference (WC), systolic (SBP) and diastolic blood pressure (DBP), and serum levels of glucose (G), triglycerides (TG) and HDL-cholesterol (HDL)) by ATP III criteria. To analyze the effect of CST on Fer we compared the basal values with those after 2-year treatment with conjugated estrogen (3.75 mg/day) and cyproterone acetate (100 mg/day) in MFT and testosterone gel (50 mg/day) in FMT.
Results: Baseline Fer was significantly correlationed with HOMA-IR and QUICKI (r=0.242, P=0.014; and r=−0.330, P=0.016, respectively), and with those of WC, G, DBP, TG and HDL, but not with those of SBP or insulin. After treatment, in MFTs the Fer increased from 104.9±60.9 to 151.0±85.3 ng/ml (P=0.001) and in FMTs decreased from 41.5±53.6 to 39.6±48.6 ng/ml (P=0.001).
Conclusion: In our study the Fer is associated with IR markers and components of MetSyn. So, the transsexual patients are at risk of diabetes mellitus and cardiovascular disease. In MFTs the CST increased this risk due to the elevation in Fer, and on the contrary in FMTs the CST decreased this risk due to the fall in Fer.