Abstract
Objective
To investigate the efficacy of soy isoflavone on climacteric symptoms in postmenopausal
women.
Design
In this double-blind, randomized, placebo-controlled study, a total of 80 women (mean
age = 55.1 years), who reported 5 or more hot flush episodes per day, were randomized to
receive either 250 mg of standardized soy extract (Glycine max AT) a total of 100 mg/day of isoflavone (n = 40) or placebo (n = 40). Exclusion criteria included: contra-indication for hormone therapy (HT), chronic
gastrointestinal diseases, and users of HT within the preceding 6-months. For 10-months,
climacteric symptoms were evaluated using a score card and the menopausal Kupperman
index. Compliance and safety were also assessed. At baseline and the end of the study,
lipid and hormonal profiles, as well as vaginal, mammographic and ultrasonographic
parameters were measured. The t-test, Wilcoxon test and ANOVA were used in the statistical analysis.
Results
At baseline, the mean number of hot flushes was 9.6 ± 3.9 per day in the isoflavone group and 10.1 ± 4.9 in the placebo group (p > 0.05). After 10 months, there was a significant reduction in frequency of hot flushes
among isoflavone users when compared to those on placebo (3.1 ± 2.3 and 5.9 ± 4.3, respectively) (p < 0.001). Kupperman index mean values showed a significant reduction in both groups.
However, soy isoflavone was significantly superior to placebo, in reducing hot flush
severity (69.9% and 33.7%, respectively) (p < 0.001). Endometrial thickness, mammography, vaginal cytology, lipids and hormonal
profile did not change in both groups. No serious adverse event related to isoflavone
treatment was reported.
Conclusions
The soy isoflavone extract exerted favorable effects on vasomotor symptoms and good
compliance, providing a safe and effective alternative therapeutic for postmenopausal
women.
Keywords
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Article info
Publication history
Published online: September 20, 2007
Accepted:
August 25,
2007
Received in revised form:
August 20,
2007
Received:
March 29,
2007
Identification
Copyright
© 2007 Elsevier Ireland Ltd. Published by Elsevier Inc. All rights reserved.
