Alcohol consumption is a risk factor for breast cancer (BC), yet little is known about longitudinal alcohol consumption patterns and risk of BC. This study aimed to investigate whether trajectory profiles of alcohol consumption across adulthood were associated with risk of first primary malignant BC in postmenopausal women. At baseline, 28,720 pre-and postmenopausal women aged 50–65 years from the Danish Diet, Cancer and Health Cohort reported their average alcohol intake over the past 12 months and their average alcohol intake at the ages of 20, 30, 40, and 50 years. Alcohol consumption trajectories were estimated using latent class mixed models. BC cases were identified through record linkage to the Danish Cancer Registry. To examine associations between alcohol consumption trajectories and BC, we fitted a proportional hazard model adjusted for potential confounding factors using data from 24,543 postmenopausal women without missing covariate information. We identified 4 alcohol consumption trajectory profiles. During a median follow-up of 16.5 years, 1,591 cases of BC occurred. A mean alcohol consumption trajectory of > 10 g/day was associated with higher risk of BC (HR: 1.65, 95%CI: 1.35–2.03) compared to a mean alcohol consumption trajectory of < 6 g/day. We found no association between trajectory profiles characterized by lower alcohol intakes in early adulthood followed by increasing consumption of alcohol in adulthood compared to a consistently low intake of alcohol. Postmenopausal women drinking consistently high amounts of alcohol throughout adulthood had a higher risk of BC compared to women with a consistently low intake of alcohol.

饮酒是乳腺癌 （BC） 的危险因素，但人们对纵向饮酒模式和 BC 风险知之甚少。本研究旨在调查成年期饮酒的轨迹概况是否与绝经后妇女首次原发性恶性 BC 的风险相关。在基线时，来自丹麦饮食、癌症和健康队列的 28,720 名 50-65 岁的绝经前和绝经后妇女报告了她们过去 12 个月的平均饮酒量以及 20、30、40 和 50 岁的平均饮酒量。使用潜在类别混合模型估计饮酒轨迹。BC 病例是通过与丹麦癌症登记处的记录联系确定的。为了检查饮酒轨迹与 BC 之间的关联，我们使用来自 24,543 名绝经后妇女的数据拟合了一个比例风险模型，该模型针对潜在的混杂因素进行了调整，而没有遗漏协变量信息。我们确定了 4 个酒精消费轨迹概况。在中位随访 16.5 年期间，发生了 1,591 例 BC。与 < 6 克/天的平均饮酒轨迹相比，> 10 克/天的平均饮酒轨迹与 BC 风险较高相关 （HR： 1.65,95%CI： 1.35-2.03）。我们发现，与持续低酒精摄入量相比，以成年早期较低酒精摄入量为特征，然后成年期饮酒量增加的轨迹特征之间没有关联。与持续低饮酒量的女性相比，整个成年期持续大量饮酒的绝经后女性患 BC 的风险更高。