Department of Epidemiology, Institute of Geriatrics, Chinese PLA (People's Liberation Army) General Hospital, China; Beijing Key Laboratory of Aging and Geriatrics, Chinese PLA General Hospital, China.
Department of Nanomedicine, Houston Methodist Research Institute, Houston, USA.
Clin Nutr. 2017 Jun;36(3):730-736. doi: 10.1016/j.clnu.2016.05.015. Epub 2016 May 30.
BACKGROUND & AIMS: Previous epidemiological studies have provided inconsistent conclusions on the impact of coffee consumption in the developing of cognitive disorders. However, no previous meta-analysis has pooled the evidence from the prospective cohort studies to assess the influence of coffee drinking and its potential dose-response patterns on the risk of developing cognitive disorders specifically.
Two databases (PubMed and Embase) were searched for evidence of cohort studies from inception to February 2016. We used a generic inverse-variance method with a random-effects model to pool the fully adjusted relative risks (RRs) and the corresponding 95% confidence intervals (CIs). In the dose-response analyses, a generalized least-squares trend estimation model was applied to computing the study-specific slopes.
Nine prospective cohort studies involving 34,282 participants were included in our study. The duration of follow-up years ranged from 1.3 to 28. Compared with <1 cup, daily drinking of 1-2 cups of coffee was inversely linked with the occurrence of cognitive disorders (i.e., Alzheimer's disease, dementia, cognitive decline, and cognitive impairment), and the pooled RR (95% CI) was 0.82 (0.71, 0.94) with evidence of non-significant heterogeneity (I = 25%). Non-significant differences were presented for the association between coffee consumption (>3 vs. <1 cup/d) and incident cognitive disorders. The dose-response analysis showed a "J-shaped" curve relationship of the risk of developing cognitive disorders with coffee consumption.
A "J-shaped" association was presented between coffee intake and incident cognitive disorders, with the lowest risk of incident cognitive disorders at a daily consumption level of 1-2 cups of coffee.
既往的流行病学研究对于咖啡摄入与认知障碍发展之间的关系得出了不一致的结论。然而，既往的荟萃分析并未对前瞻性队列研究进行综合评估，以评估喝咖啡及其潜在剂量-反应模式对特定认知障碍发生风险的影响。
从建库至 2016 年 2 月，我们在 2 个数据库（PubMed 和 Embase）中搜索队列研究证据。我们采用一般逆方差法和随机效应模型来汇总完全校正的相对风险（RR）及其相应的 95%置信区间（CI）。在剂量-反应分析中，采用广义最小二乘趋势估计模型计算研究特异性斜率。
本研究共纳入 9 项前瞻性队列研究，涉及 34282 名参与者。随访年限为 1.3-28 年。与<1 杯相比，每日饮用 1-2 杯咖啡与认知障碍（即阿尔茨海默病、痴呆、认知衰退和认知损害）的发生呈负相关，汇总 RR（95%CI）为 0.82（0.71，0.94），异质性无统计学意义（I²=25%）。每日饮用>3 杯咖啡与认知障碍的相关性也无统计学意义。剂量-反应分析显示，咖啡摄入与认知障碍发生风险呈“J 形”曲线关系。
咖啡摄入量与新发认知障碍呈“J 形”关联，每日饮用 1-2 杯咖啡时新发认知障碍风险最低。
