Division of Epidemiology, Department of Health Informatics and Public Health, Graduate School of Medicine, Tohoku University School of Public Health, 2-1, Seiryo-Machi, Aoba-Ku, Sendai, Miyagi, 980-8575, Japan.
Eur J Nutr. 2023 Oct;62(7):2751-2761. doi: 10.1007/s00394-023-03189-7. Epub 2023 Jun 19.
To investigate the association between dairy intake and risk of incident dementia in older adults.
A longitudinal analysis of dairy intake with incident dementia was conducted using a cohort study of 11,637 non-disabled Japanese older adults aged ≥ 65 years followed-up for up to 5.7 years (mean: 5.0 years). Data on milk, yogurt, and cheese intake were collected using a validated food frequency questionnaire. Total dairy intake was calculated as the sum of the daily intake of milk, yogurt, and cheese, which was sex-specifically categorized in quintiles. Dementia cases were retrieved from the public long-term care insurance database. Cox proportional hazards model was used to estimate multivariable hazard ratios (HRs) and 95% confidence intervals (95% CIs) for incident dementia.
During 58,013 person-years of follow-up, 946 persons developed dementia. In the primary analysis, compare to the lowest quintile of total dairy intake, Q2 showed a slightly decreased incident dementia risk (HR for Q2 vs Q1: 0.90, 95% CI: 0.73-1.10) after fully adjusted for demographic, lifestyle, psychological, and nutritional factors, and diseases history. Compared to non-consumers of milk, those consuming for 1-2 times/month showed a lower risk of incident dementia (fully-adjusted HR: 0.76, 95% CI: 0.57-1.02). Daily yogurt consumers also had a reduced risk (fully-adjusted HR: 0.89, 95% CI: 0.74-1.09). But daily cheese consumers showed an increased risk of dementia (fully-adjusted HR: 1.28, 95% CI: 0.91-1.79). In the sensitivity analysis where we excluded dementia cases ascertained in the first 2 years, results were consistent with those from the primary analysis and we further found that yogurt intake might be inversely associated with dementia risk (p for trend = 0.025).
Low total dairy intake or low milk intake frequency might be associated with lower incident dementia risk, however daily cheese consumers seemed to have an increased risk. Our study also suggested a possible inverse dose-response association between yogurt consumption and dementia risk, but further studies are needed to confirm whether this benefit was from yogurt intake itself or as a part of a healthy dietary pattern.
探讨老年人乳制品摄入与新发痴呆风险的关系。
采用一项队列研究，对 11637 名无残疾的日本老年人进行了乳制品摄入与新发痴呆的纵向分析，这些老年人年龄≥65 岁，随访时间长达 5.7 年（平均：5.0 年）。使用经过验证的食物频率问卷收集了关于牛奶、酸奶和奶酪摄入的数据。乳制品总摄入量是通过将牛奶、酸奶和奶酪的每日摄入量相加计算得出的，其摄入量在性别特异性的五分位数中进行了分类。痴呆病例是从公共长期护理保险数据库中检索到的。使用 Cox 比例风险模型估计了多变量风险比（HR）和 95%置信区间（95%CI）与新发痴呆相关的风险。
在 58013 人年的随访期间，有 946 人发生了痴呆。在主要分析中，与总乳制品摄入量最低的五分位数相比，Q2 显示新发痴呆风险略有降低（Q2 与 Q1 相比：0.90，95%CI：0.73-1.10），经过充分调整人口统计学、生活方式、心理和营养因素以及疾病史后。与不食用牛奶的人相比，每月食用 1-2 次牛奶的人发生新发痴呆的风险较低（充分调整 HR：0.76，95%CI：0.57-1.02）。每天食用酸奶的人也有较低的风险（充分调整 HR：0.89，95%CI：0.74-1.09）。但是，每天食用奶酪的人痴呆风险增加（充分调整 HR：1.28，95%CI：0.91-1.79）。在敏感性分析中，我们排除了前 2 年确定的痴呆病例，结果与主要分析一致，我们还发现酸奶摄入可能与痴呆风险呈负相关（趋势检验 P 值=0.025）。
总乳制品摄入量低或牛奶摄入频率低可能与新发痴呆风险降低有关，但每日奶酪消费者的痴呆风险似乎增加。我们的研究还表明，酸奶摄入与痴呆风险之间可能存在负剂量反应关系，但需要进一步的研究来确认这种益处是否来自酸奶摄入本身还是作为健康饮食模式的一部分。
