Hypothalamic-pituitary-thyroid axis function in women with a menstrually related mood disorder: association with histories of sexual abuse.

INTRODUCTION: We previously reported a unique hypothalamic-pituitary-thyroid (HPT) axis profile in women with a menstrually related mood disorder (MRMD) who also had a history of sexual abuse (SA). In the present study, we sought to extend that work by examining the association of an SA history with HPT-axis disturbance in both women with MRMD and women without MRMD.
METHODS: Fifty-seven women met the prospective criteria for MRMD (23 with an SA history), and 52 women were non-MRMD (18 with an SA history). Thyroid-stimulating hormone, thyroxin (T4; total and free), and triiodothyronine (T3; total and free) were evaluated in serum, together with thyroid hormone ratios reflecting T4 to T3 conversion.
RESULTS: Women with MRMD, compared with women without MRMD, had elevated T3/T4 ratios (p values ≤ .01; reflecting increased conversion of T4 to T3) and lower free and total T4 concentrations (p values = .01). Higher T3/T4 ratios and lower T4 concentrations predicted more severe premenstrual symptoms in all women. An SA history, irrespective of MRMD status, was associated with elevated thyroid-stimulating hormone concentrations (p = .03). However, in women with MRMD, an SA history was associated with elevated T3 concentrations (p = .049), whereas in women without MRMD, an SA history was associated with decreased T3 concentrations (p = .02).
CONCLUSIONS: An MRMD and an SA history are associated with independent and interactive effects on the HPT axis. The evidence that an MRMD moderates the influence of SA on T3 concentrations contributes to a growing body of work suggesting that an SA history may identify a distinct subgroup of women with MRMD.