Endocrine Abstracts

Introduction: Our previous research suggested that a history of sexual abuse (SA) may impact thyroid axis profiles differently in women with menstrually related mood disorder (MRMD) compared with non-MRMD women but was limited by a small sample of non-MRMD women with SA. The current study was designed to study a larger sample of MRMD and non-MRMD women with SA to evaluate whether MRMD status moderates the effects of SA on thyroid axis function.

Methods: A total of 109 women (aged 34±8 years) were prospectively evaluated for current diagnosis of MRMD according to the DSM-IV criteria; for SA histories using a validated interview; for depressive symptoms using the beck depression inventory (BDI); and for serum concentrations of free T₃ (FT₃) and free T₄ (FT₄). The FT₃/FT₄ ratio, that provides an index of the peripheral conversion of T₄ to T₃, was also calculated.

Results: Fifty-seven women met criteria for MRMD (23 with SA histories and 34 without SA histories) and 52 women were enrolled as non-MRMD controls (18 with SA histories and 34 without SA histories). There was a significant MRMD×SA interaction for FT₃ concentrations (F(108,3)=4.07; P=0.04), since non-MRMD women with SA histories had lower FT₃ concentration than all other groups (ps<0.05). Only for non-MRMD women with SA histories, lower FT₃ predicted higher BDI scores (ρ=−0.51, P=0.046).

MRMD women, when compared to non-MRMD women, had lower FT₄ concentrations (F(108,1)=5.82; P=0.02) and higher FT₃/FT₄ ratio (F(108,1)=14.99; P<0.001).

Conclusions: Our results suggest that MRMD diagnosis moderates the influence of SA on FT₃ concentrations. Lower FT₃ concentrations are associated with increased depressive symptoms in non-MRMD women who have SA histories. For MRMD women, regardless of SA history, there is increased peripheral conversion of T₄ to T₃, consistent with a defense reaction and more recently conceptualizations that PMDD represents a stress-related disorder.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This work was supported, however funding details unavailable.