Fluctuating serotonergic function in premenstrual dysphoric disorder and premenstrual syndrome: findings from neuroendocrine challenge tests.

RATIONALE: Premenstrual dysphoric disorder (PMDD) has been assumed to be a subtype of premenstrual syndrome (PMS) with depressive symptoms, such as depressive mood, tension, anxiety, and mood liability during luteal phase. At present, no conclusion has been established about serotonergic function in PMDD.

OBJECTIVE: The purpose of this study was to investigate the serotonergic function of PMDD subjects in comparison to PMS without PMDD subjects and normal controls via neuroendocrine challenge tests.

SUBJECTS AND METHODS: Twenty-four women (seven with PMDD, eight with PMS without PMDD, and nine normal controls) were tested on three occasions (follicular phase, early luteal phase, and late luteal phase) receiving paroxetine 20 mg orally as a serotonergic probe at 8:00 A: .M: . Plasma ACTH and cortisol were measured prior to the administration and every hour for 6 h thereafter.

RESULTS: As a whole, there were significant differences in serotonergic function measured by ACTH and cortisol responses to paroxetine challenge across these three groups. PMDD subjects showed higher serotonergic function in follicular phase but lower serotonergic function in luteal phase, compared with women with PMS without PMDD and normal controls.

CONCLUSION: The present findings suggest that PMDD women have fluctuating serotonergic function across their menstrual cycles and that the pattern may be different from PMS without PMDD.