National Center for Epidemiology, Instituto de Salud Carlos III, Madrid, Spain.
Breast Cancer Res Treat. 2011 Aug;129(1):135-47. doi: 10.1007/s10549-011-1414-5. Epub 2011 Mar 4.
Mammographic density (MD), or the proportion of the breast with respect to its overall area that is composed of dense tissue, is a strong risk factor for breast cancer. Studies support a positive association of mammographic density and alcohol drinking. This was a cross-sectional multicenter study based on 3584 women, aged 45-68 years, recruited from seven screening centers within the Spanish breast cancer screening program network. The association between MD, alcohol consumption and tobacco use was evaluated by using ordinal logistic models with random center-specific intercepts. We found a weak positive association between current alcohol intake and higher MD, with current alcohol consumption increasing the odds of high MD by 13% (OR = 1.13; 95% CI 0.99-1.28) and high daily grams of alcohol being positively associated with increased MD (P for trend = 0.045). There were no statistically significant differences in MD between smokers and non-smokers. Nevertheless, increased number of daily cigarettes and increased number of accumulated lifetime cigarettes were negatively associated with high MD (P for trend 0.017 and 0.021). The effect of alcohol on MD was modified by menopausal status and tobacco smoking: whereas, alcohol consumption and daily grams of alcohol were positively associated with higher MD in postmenopausal women and in women who were not currently smoking, alcohol consumption had no effect on MD in premenopausal women and current smokers. Our results support an association between recent alcohol consumption and high MD, characterized by a modest increase in risk at low levels of current consumption and a decrease in risk among heavier drinkers. Our study also shows how the effects of alcohol in the breast can be modified by other factors, such as smoking.
乳腺密度（MD），即乳房整体面积中由致密组织组成的比例，是乳腺癌的一个强烈危险因素。研究支持乳腺密度与饮酒之间存在正相关关系。这是一项基于西班牙乳腺癌筛查计划网络内七个筛查中心的 3584 名年龄在 45-68 岁的女性的横断面多中心研究。使用带有随机中心特定截距的有序逻辑模型评估 MD、酒精消耗和吸烟之间的关联。我们发现当前饮酒与更高的 MD 之间存在微弱的正相关关系，当前饮酒使 MD 较高的几率增加 13%（OR=1.13；95%CI 0.99-1.28），而每日饮酒量与 MD 增加呈正相关（趋势 P=0.045）。吸烟者和不吸烟者之间的 MD 没有统计学上的显著差异。然而，每日吸烟量和累计吸烟量与 MD 较高呈负相关（趋势 P=0.017 和 0.021）。酒精对 MD 的影响受绝经状态和吸烟状况的影响：然而，在绝经后妇女和目前不吸烟的妇女中，饮酒和每日饮酒量与更高的 MD 呈正相关，而在绝经前妇女和目前吸烟者中，饮酒对 MD 没有影响。我们的研究结果支持了近期饮酒与高 MD 之间的关联，这种关联在低水平的当前饮酒量时风险略有增加，而在饮酒量较高的人群中风险降低。我们的研究还表明，酒精对乳房的影响可以通过其他因素（如吸烟）来改变。
