Serum triiodothyronine elevation with posttraumatic stress disorder: a cross-cultural study

This study examines the thyroid hormonal profile in Israeli combat veterans with posttraumatic stress disorder (PTSD) and compares it with the previously reported profile in American Vietnam combat veterans with PTSD. Eleven male combat veterans with PTSD were compared with 11 normal subjects. Thyroid junction was evaluated by the measurement of serum total triiodothyronine (TT3), free triiodothyronine (FT3), total thyroxine (TT4), free thyroxine (FT4), thyroxine-binding globulin (TBG), and thyroid-stimulating hormone (TSH). The mean total T3 level in the Israeli PTSD patients (160.5 ng/dL) was significantly elevated (t = 2.53, p < .02) above that of the comparison group (135.5 ng/dL). Total T3 mean levels were not significantly different between the Israeli PTSD group and two American PTSD groups, but all three PTSD groups had significantly higher total T3 levels than both Israeli and American comparison groups. This preliminary study indicates that T3 elevation in combat-related PTSD may extend across cultures and suggests that further comparison of Israeli and American PTSD and normal groups may be useful in evaluating the significance and implications of the unusual alterations in the thyroid system in PTSD.