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Influence of the CYP17 polymorphism on vasomotor symptoms in postmenopausal women: a pilot study
R C Nogueira1, A M Massad Costa, I D C G Silva
1Federal University of São Paulo, Gynecology Department, São Paulo, Brazil.
Objective:
To evaluate the influence of CYP17 polymorphism on menopausal symptoms after estrogen treatment.
Methods:
A total of 130 women were recruited, but only 100 of these were selected according to inclusion and exclusion criteria; they were treated with 0.3 mg/day conjugated equine estrogens. One year later, the study was completed by 71 women. The analysis of the Kupperman menopausal index symptoms was made with information provided by the patients on daily diary cards. Blood samples were analyzed and the women were divided into two groups based on the CYP17, 5'-untranslated region: group A (wild-type homozygote and heterozygote) and group B (mutated homozygote).
Results:
The values for the Kupperman menopausal index were similar in both groups at baseline. The symptoms in both groups decreased after 1 year of treatment when compared to those at baseline. The improvement rate was approximately 27.09% and 32.18%, in groups A and B, respectively. The levels of estrogen after treatment were higher in both groups in comparison with the baseline values. The testosterone level rose in group B with the 1-year treatment (0.48 + 0.16 ng/ml), reaching a higher level than the level in group A after treatment. The sex hormone binding globulin (SHBG) level showed a significant increase after the 1-year treatment in group B, surpassing both the baseline and the after-treatment values in group A (p < 0.01).
Conclusion:
Our data suggest that the CYP17 polymorphism did not influence the action of estrogen on menopause symptoms during the 1-year treatment. The extra production of estrogen and androgen may have been countered by the elevation of SHBG levels.
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