Clinical effects of a standardized soy extract in postmenopausal women: A pilot study

Objective: This double-blind, randomized study was aimed at evaluating comp aratively, in postmenopausal women, the activity of a standardized soy extr act (SOYSELECT) and placebo when given alone or in combination with conjuga ted equine estrogens (CEE) on early climacteric symptoms. Lipid profile, pi tuitary hormones, osteocalcin and endothelin levels, and vaginal and endome trial parameters were also evaluated. Design: Participants in the control group were given placebo, and participa nts in the treated group were given 400 mg/day of a standardized soy extrac t, corresponding to 50 mg/daily of isoflavones. After 6 weeks of treatment, CEE was also then given to each participant at a dose of 0.625 mg/day for 4 weeks. At the end of this period, soy and placebo treatment were suspende d, and, until the end of the study (week 12), participants were administere d 10 mg/day of medroxyprogesterone acetate in association with CEE (0.625 m g/day). Results: When compared with pretreatment data, on week 6 of the study, a si gnificant (p < 0.01) reduction in the mean number of hot flushes per week w as observed in participants who were receiving the standardized soy extract , whereas a more marked relief was observed in both soy and placebo groups during CEE administration. Concurrently, the severity of hot flushes, asses sed by means of the Greene climacteric scale, was also reduced in the soy g roup participants (p < 0.001, by paired t-test). No soy-related changes wer e observed on vaginal cytology, endometrial thickness, uterine artery pulsa tility index, or metabolic and hormonal parameters tested. Finally, GEE-rel ated changes on genital tract, uterine vascular compartment, and pituitary hormones were not modified by soy treatment. Conclusions: SOYSELECT may be a safe and efficacious therapy for relief of hot flushes in women who refuse or have contraindications for hormone repla cement therapy. (Menopause 2000;7:105-111, (C) 2000, The North American Men opause Society.).