Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York, NY.
College of Pharmacy, University of Michigan, Ann Arbor, MI.
Diabetes Care. 2023 Sep 1;46(9):1673-1680. doi: 10.2337/dc23-0656.
We sought to examine the mediating role of changes in depressive symptoms in the association between chronic hyperglycemia and longitudinal cognition in a sample of older adults with type 2 diabetes (T2D).
We conducted a longitudinal mediation analysis using structural equation modeling of observational data collected over 6 years from 2,155 participants with T2D (aged ≥51 years) in the U.S.-wide Health and Retirement Study. T2D was defined using self-reported diagnosis, and HbA1c was assessed at study baseline. Self-reported depressive symptoms were assessed at two time points 4 years apart. Episodic memory was measured using a list-learning test administered at three time points over 6 years. We adjusted for sociodemographics, chronic health comorbidities, medication adherence, study enrollment year, and prior years' depressive symptoms and memory scores.
At baseline, participants' mean age was 69.4 (SD = 9.1), mean HbA1c was 7.2% (SD = 1.4%), 55.0% were women, 19.3% were non-Latinx Black, and 14.0% were Latinx. Higher baseline levels of HbA1c were associated with increases in depressive symptoms over 4 years, which, in turn, were associated with poorer memory 2 years later. Depressive symptoms accounted for 19% of the longitudinal effect of HbA1c on memory over the 6-year period. Sensitivity analyses ruled out alternative directions of associations.
Incident elevations in depressive symptoms mediated the longitudinal association between hyperglycemia and 6-year episodic memory scores. For older adults with T2D, interventions to prevent HbA1c-related incident depressive symptoms may be beneficial in reducing the neurotoxic effects of chronic hyperglycemia on cognition.
我们旨在研究在患有 2 型糖尿病（T2D）的老年人样本中，慢性高血糖与纵向认知之间的关联中，抑郁症状变化的中介作用。
我们使用来自美国健康与退休研究的 2155 名 T2D 患者（年龄≥51 岁）的 6 年观察数据，通过结构方程模型进行了纵向中介分析。T2D 使用自我报告的诊断定义，HbA1c 在研究基线时进行评估。抑郁症状在 4 年的两个时间点进行自我报告评估。情节记忆使用在 6 年内的三个时间点进行的列表学习测试进行测量。我们调整了社会人口统计学、慢性合并症、药物依从性、研究入组年份以及前几年的抑郁症状和记忆评分。
在基线时，参与者的平均年龄为 69.4（SD=9.1），平均 HbA1c 为 7.2%（SD=1.4%），55.0%为女性，19.3%为非拉丁裔黑人，14.0%为拉丁裔。较高的基线 HbA1c 水平与 4 年内抑郁症状的增加有关，而抑郁症状的增加又与 2 年后的记忆较差有关。抑郁症状解释了 HbA1c 对记忆的 6 年纵向影响的 19%。敏感性分析排除了其他方向的关联。
新发抑郁症状升高中介了高血糖症与 6 年情节记忆评分之间的纵向关联。对于患有 T2D 的老年人来说，预防 HbA1c 相关新发抑郁症状的干预措施可能有益于减少慢性高血糖对认知的神经毒性影响。
