Wilson R S, Schneider J A, Boyle P A, Arnold S E, Tang Y, Bennett D A
Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL 60612, USA.
Neurology. 2007 Jun 12;68(24):2085-92. doi: 10.1212/01.wnl.0000264930.97061.82.
Mild cognitive impairment (MCI) is associated with increased morbidity and mortality but its development is not well understood. Here we test the hypothesis that chronic psychological distress is associated with increased incidence of MCI in old age.
Participants are older persons from two cohort studies with uniform annual clinical evaluations which included detailed cognitive testing and clinical classification of MCI. We excluded persons with dementia or MCI at baseline; follow-up data were available on 1,256 persons without cognitive impairment (95% of those eligible). At baseline, they completed a six-item measure of neuroticism (mean = 15.6, SD = 6.6), an indicator of the tendency to experience psychological distress.
During up to 12 years of follow-up, 482 persons (38%) developed MCI. Risk of MCI increased by about 2% for each one unit increase on the distress scale (relative risk [RR] = 1.02; 95% CI: 1.01, 1.04), with the association slightly stronger in men than women. Overall, a distress-prone person (score = 24, 90th percentile) was about 40% more likely to develop MCI than someone not prone to distress (score = 8, 10th percentile). Adjustment for depressive symptomatology at baseline did not substantially change results (RR = 1.02; 95% CI: 1.00, 1.03). Depressive symptoms were also related to risk of MCI but not after controlling for distress score. In mixed-effects models, higher distress score was associated with lower level of function in multiple cognitive domains at baseline and more rapid cognitive decline, especially in episodic memory.
Among older persons without manifest cognitive impairment, higher level of chronic psychological distress is associated with increased incidence of mild cognitive impairment.
轻度认知障碍（MCI）与发病率和死亡率的增加相关，但其发展过程尚未完全明确。在此，我们检验以下假设：慢性心理困扰与老年人MCI发病率的增加有关。
参与者来自两项队列研究中的老年人，这些研究每年进行统一的临床评估，包括详细的认知测试和MCI的临床分类。我们排除了基线时患有痴呆或MCI的人；共有1256名无认知障碍的人（占符合条件者的95%）有随访数据。在基线时，他们完成了一项包含六个条目的神经质测量（均值 = 15.6，标准差 = 6.6），这是一种体验心理困扰倾向的指标。
在长达12年的随访期间，482人（38%）发展为MCI。在困扰量表上，每增加一个单位，MCI的风险增加约2%（相对风险[RR] = 1.02；95%置信区间：1.01，1.04），男性中的关联略强于女性。总体而言，易产生困扰的人（得分 = 24，第90百分位数）比不易产生困扰的人（得分 = 8，第10百分位数）患MCI的可能性高约40%。对基线时的抑郁症状进行调整后，结果没有实质性变化（RR = 1.02；95%置信区间：1.00，1.03）。抑郁症状也与MCI风险相关，但在控制困扰得分后则不然。在混合效应模型中，较高的困扰得分与基线时多个认知领域的较低功能水平以及更快的认知衰退相关，尤其是在情景记忆方面。
在无明显认知障碍的老年人中，较高水平的慢性心理困扰与轻度认知障碍发病率的增加有关。
