Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, 615 North Wolfe Street, Baltimore, MD 21205, USA.
Diabetologia. 2011 Jul;54(7):1645-52. doi: 10.1007/s00125-011-2095-7. Epub 2011 Mar 1.
AIMS/HYPOTHESIS: This study aimed to examine the association between diabetes and hyperglycaemia-assessed by HbA(1c)-and change in cognitive function in persons with and without diabetes.
This was a prospective cohort study of 8,442 non-diabetic and 516 diabetic participants in the Atherosclerosis Risk in Communities (ARIC) study. We examined the association of baseline categories of HbA(1c) with 6 year change in three measures of cognition: the digit symbol substitution test (DSST); the delayed word recall test (DWRT); and the word fluency test (WFT). Our primary outcomes were the quintiles with the greatest annual cognitive decline for each test. Logistic regression models were adjusted for demographic (age, sex, race, field centre, education, income), lifestyle (smoking, drinking) and metabolic (adiposity, blood pressure, cholesterol) factors.
The mean age was 56 years. Women accounted for 56% of the study population and 21% of the study population were black. The mean HbA(1c) was 5.7% overall: 8.5% in persons with and 5.5% in persons without diabetes. In adjusted logistic regression models, diagnosed diabetes was associated with cognitive decline on the DSST (OR 1.42, 95% CI 1.14-1.75, p = 0.002), but HbA(1c) was not a significant independent predictor of cognitive decline when stratifying by diabetes diagnosis (diabetes, p trend = 0.320; no diabetes, p trend = 0.566). Trends were not significant for the DWRT or WFT in either the presence or the absence of diabetes.
CONCLUSIONS/INTERPRETATION: Hyperglycaemia, as measured by HbA(1c), did not add predictive power beyond diabetes status for 6 year cognitive decline in this middle-aged population. Additional work is needed to identify the non-glycaemic factors by which diabetes may contribute to cognitive decline.
目的/假设：本研究旨在探讨糖尿病患者和非糖尿病患者中，糖化血红蛋白（HbA1c）评估的糖尿病和高血糖与认知功能变化之间的关系。
这是一项对动脉粥样硬化风险社区（ARIC）研究中的 8442 名非糖尿病患者和 516 名糖尿病患者进行的前瞻性队列研究。我们检查了基线 HbA1c 分类与 6 年三种认知测试变化的关系：数字符号替换测试（DSST）；延迟单词回忆测试（DWRT）；和单词流畅性测试（WFT）。我们的主要结局是每个测试中每年认知下降最大的五分位数。逻辑回归模型调整了人口统计学因素（年龄、性别、种族、研究中心、教育、收入）、生活方式（吸烟、饮酒）和代谢因素（肥胖、血压、胆固醇）。
平均年龄为 56 岁。女性占研究人群的 56%，黑人占 21%。HbA1c 的平均值为 5.7%：糖尿病患者为 8.5%，非糖尿病患者为 5.5%。在调整后的逻辑回归模型中，诊断为糖尿病与 DSST 的认知下降相关（OR 1.42，95%CI 1.14-1.75，p=0.002），但在按糖尿病诊断分层时，HbA1c 不是认知下降的独立预测因子（糖尿病，p 趋势=0.320；无糖尿病，p 趋势=0.566）。无论是否存在糖尿病，DWRT 或 WFT 均无明显趋势。
结论/解释：在这个中年人群中，糖化血红蛋白（HbA1c）测量的高血糖并不能为糖尿病患者 6 年的认知下降提供超过糖尿病状态的预测能力。需要进一步研究以确定糖尿病导致认知能力下降的非血糖因素。
