Low-dose conjugated equine estrogens elevate circulating neurotransmitters and improve the psychological well-being of menopausal women

OBJECTIVE: To assess the effect of low-dose conjugated equine estrogens (E) on circulating neurotransmitters and the efficacy for the treatment of psychological symptoms. DESIGN: Controlled comparative clinical study. SETTING: Endocrine Research Unit, Instituto Mexicano del Seguro Social, Mexico. PATIENT(S): Thirty postmenopausal women received conjugated equine E. Ten women acted as a comparison group. INTERVENTION(S): Conjugated equine E, 0.312 mg/day, for 21 days per cycle during six cycles and added chlormadinone acetate, 2 mg/day, for the last 5 days of each cycle. Green scale for climateric women and Blatt-Kupperman Menopausal Index were used for measuring psychological well-being. MAIN OUTCOME MEASURE(S): Serum levels of dopamine (DA), noradrenaline, serotonin, and beta-endorphin were quantified by specific assays at baseline and at the end of treatment. RESULT(S): Low baseline levels of DA, serotonin, and beta-endorphin increased significantly (P<.001) from 181.9 +/- 47.8 pg/mL to 202.9 +/- 32.8 pg/mL (mean +/- SD); from 206.4 +/- 94.2 ng/mL to 279.2 +/- 67.9 ng/mL; from 11.2 +/- 1.8 pmol/L to 13.8 +/- 2.4 pmol/L, respectively, after conjugated equine E. In parallel, augmented baseline noradrenaline levels diminished significantly (P<.05) from 30.2 +/- 4.7 ng/mL to 24.0 +/- 4.7 ng/mL. All neurotransmitter levels had a significant correlation with 17beta-E(2) concentrations at the end of the study. Alleviation of psychological symptoms was observed in all but eight treated women. CONCLUSION(S): Low-dose conjugated equine E associated with periodic administration of chlormadinone acetate elicited favorable changes in neurotransmitters and relieved psychological symptoms.