Objective: To asses possible differences in serum-free triiodothironine (FT3), total triiodothironine (TT3), free thyroxine, total thyroxine, and thyroid-stimulating hormone levels between male combat veterans with chronic post-traumatic stress disorder and healthy male control subjects.
Method: Male combat veterans (N = 38; ages 23-53 years; mean +/- SD = 35.9 +/- 7.5 years) with chronic post-traumatic stress disorder (duration of illness was 2-6 years; mean +/- SD = 3.53 +/- 0.95 years) were compared with healthy male control subjects (N = 32; ages 25-50 years; mean +/- SD = 36.5 +/- 8.3 years). Serum samples were analyzed by luminoimmunochemical assays for basal levels of thyroid-stimulating hormone, total thyroxine, TT3, free thyroxine, and FT3.
Results: Combat veterans with chronic combat-related post-traumatic stress disorder had significantly increased values of FT3 (mean +/- SD, 5.92 +/- 1.11; t = 2.27; p < 0.02), as well as TT3 (mean +/- SD, 2.04 +/- 0.32; t = 6.26; p < 0.0001) than the control group.
Conclusion: Elevated serum TT3 and FT3 are associated with chronic combat-related post-traumatic stress disorder.