Hypothyroid-Like Alterations in Testosterone Metabolism in Anorexia Nervosa

Abstract

The metabolism of ¹⁴C-testosterone was studied in 8 severely underweight young women with anorexia nervosa. The urinary androsterone/etiocholanolone (A/E) ratio was uniformly low, in a range characteristic of hypothyroidism; the patients also showed low plasma concentrations of triiodothyronine (T₃). Clinical remission as manifested by weight gain was accompanied by concomitant increases of the A/E ratio and the plasma T, concentration to or toward normal. The administration of T₃ also resulted in a shift of the A/E ratio toward normal. These data demonstrate that the low plasma T₃ concentrations in patients with anorexia nervosa may be related to the development of one of the characteristic biochemical abnormalities found in clinical hypothyroidism, namely a decreased A/E ratio. These data suggest that the “low T₃ syndrome” may be associated with biochemical hypothyroidism.