(2025-12-30) Zubiaurre-Elorza, Leire; Uribe, Carme; Marcos, Alberto; Fernández, Rosa; Pásaro, Eduardo; Rodríguez Del Cerro, María Cruz; Burke, Sarah M.; Guillamón Fernández, Antonio; European Commission; Agencia estatal de Investigación (España)
Gender-affirming hormone therapy (GAHT) is a medical treatment used to help trans- gender individuals align their physical appearance with their gender identity. GAHT in transgender women (TW) has been found to lead to a reduction in brain tissue with an expansion of the ventricles. We discuss an animal model studying the effects of GAHT that suggests dehydration of brain tissue and an alteration in the relative con- centration of brain metabolites. We hypothesize that estradiol, acting on astrocytes, alters cerebral blood flow, water metabolism, and metabolite concentration and argue that these changes could explain the higher risk of stroke observed n GAHT-treated TW compared to untreated cisgender men. Future studies should clarify the mecha- nisms underlying the brain tissue changes induced by GAHT.
