Alcohol consumption in relation to plasma sex hormones, prolactin and sex hormone-binding globulin in premenopausal women
Menée aux Etats-Unis, cette étude évalue l'association entre une consommation d'alcool, le niveau plasmatique d'hormones sexuelles avant la ménopause et le risque de cancer du sein
Background: Alcohol consumption is a consistent risk factor for breast cancer, and evidence suggests premenopausal plasma hormones are associated with breast cancer. Methods: Plasma concentrations of estradiol, estrone, estrone sulfate, testosterone, androstenedione, progesterone, prolactin, dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulphate (DHEAS), and sex hormone-binding globulin (SHBG) were measured in samples collected in 1996-99. Average alcohol intake was calculated from semi-quantitative food frequency questionnaires collected in 1995 and 1999. We used generalized linear models to calculate geometric mean hormone concentrations across alcohol categories and the percent difference for the highest vs. lowest category. Results: Comparing women who consumed >20 g/day with non-drinkers, levels were 25.7% higher for luteal estrone (geometric mean 106 vs. 84.5 pg/mL, trend test p-value=0.001), 27.2% higher for luteal estradiol (182 vs. 143 pg/mL, trend test p-value=0.006), and 16.8% higher for SHBG (85.6 vs. 73.3 nmol/L, trend test p-value =0.03); concentrations of free testosterone were 17.9% lower (0.16 vs. 0.20 ng/dL, trend test p-value=0.002). Women consuming >10g/day compared to non-drinkers had 26.5% higher concentrations of follicular estrone sulfate (950 vs. 751 pg/mL, trend test p-value=0.04). We did not observe significant associations between alcohol and the other sex hormones evaluated. Significant positive associations were observed with beer intake, but not other alcohol types, for DHEA (p-interaction=0.003) and androstenedione (p-interaction=0.006). Conclusion: Alcohol consumption was significantly positively associated with plasma luteal estrogen concentrations, but not with androgen levels, nor estrone or estradiol measured in the follicular phase. Impact: Differences in premenopausal estrogen levels may contribute to the association between alcohol and breast cancer.