Age-associated cognitive changes in community dwelling adults

尽管临床心脑血管疾病是认知功能下降和痴呆的危险因素，但对于没有这些疾病的个体的血管健康和认知之间的关系知之甚少。颈动脉内膜中层厚度(IMT)是一种衡量亚临床血管疾病的指标，它与认知功能的同时下降有关，但相对较少的研究探讨了颈动脉IMT与预期认知功能下降之间的纵向关系。我们调查了巴尔的摩老年纵向研究(BLSA)中的538名参与者(年龄在20岁至93岁之间，39%为男性，66%为白人)颈动脉IMT与预期认知功能轨迹的关系，这些参与者没有已知的心血管、脑血管和神经疾病。在长达11年的随访中，参与者接受了最初的颈动脉超声检查和重复的神经心理测试，次数多达8次。混合效应回归分析根据年龄、性别、种族、教育程度、平均动脉压、体重指数、总胆固醇、吸烟、抑郁症状和心血管药物使用情况进行了调整。颈动脉IMT较大的个体在语言和非语言记忆的多项测试中，以及语义联系流畅性和执行功能的测试中，表现出随着时间的推移表现出加速下降。颈动脉IMT预测，在没有血管和神经疾病的社区居住的个人中，认知能力下降的速度加快，特别是在记忆领域。 在第二项研究中，我们在参加巴尔的摩老龄化纵向研究的参与者中，研究了抑郁症状的纵向轨迹以及显著症状史与随后的颈动脉内中膜厚度(IMT)之间的关系。我们还评估了抑郁症状和颈动脉内膜厚度在两个时间点上的纵向协变性。先前的文献已经证实，在健康人中，抑郁症状和颈动脉内膜厚度之间的横断面关联不一致，现有的纵向研究依赖于单一时间点的抑郁评估。我们的样本包括556名参与者(303名女性和253名男性)，年龄20到93岁(平均+/-标准差=55.8+/-15.9岁)，他们在1到15年的时间里完成了流行病学研究中心抑郁(CES-D)量表的1到8次。这些BLSA参与者后来接受了高分辨率B型超声检查，以评估颈总动脉远端壁的IMT。这些参与者中的一部分(n=68)在平均3.9年后接受了IMT的重新评估。线性和混合效应回归模型根据性别、种族、教育程度、收缩压、低密度脂蛋白胆固醇、体重指数、糖尿病、吸烟以及降压、降脂和抗抑郁药物进行了调整。我们没有发现抑郁症状的轨迹或明显的抑郁症状史与未来的颈动脉IMT之间的关系。也没有证据表明抑郁症状和IMT随时间的纵向协变。其他分析也同样显示出缺乏重要的联系。在目前的健康社区志愿者样本中，抑郁症状和颈动脉IMT之间没有关联。

Although clinical cardiovascular and cerebrovascular diseases are established risk factors for cognitive decline and dementia, less is known about the relations between vascular health and cognition among individuals without these diseases. Carotid intimal medial thickness (IMT), a measure of subclinical vascular disease, is associated with concurrent decrements in cognitive function, but relatively little research has examined longitudinal relations between carotid IMT and prospective cognitive decline. We examined relations of carotid IMT to prospective trajectories of cognitive function among 538 (aged 20 to 93, 39% male, 66% white) participants in the Baltimore Longitudinal Study of Aging (BLSA) free of known cardiovascular, cerebrovascular, and neurological disease. Participants underwent initial carotid ultrasonography and repeat neuropsychological testing on up to 8 occasions over up to 11 years of follow-up. Mixed-effects regression analyses were adjusted for age, gender, race, education, mean arterial pressure, body mass index, total cholesterol, smoking, depressive symptoms, and cardiovascular medication use. Individuals with greater carotid IMT displayed accelerated decline in performance over time on multiple tests of verbal and nonverbal memory, as well as a test of semantic association fluency and executive function. Carotid IMT predicts accelerated cognitive decline, particularly in the domain of memory, among community-dwelling individuals free of vascular and neurological disease. In a second study, we examined the relation between longitudinal trajectories of depressive symptoms as well as history of significant symptoms and subsequent carotid intimal medial thickness (IMT) among participants enrolled in the Baltimore Longitudinal Study of Aging. We also assessed longitudinal covariation of depressive symptoms and carotid IMT over two time points. Prior literature has identified inconsistent cross-sectional associations between depressive symptoms and carotid IMT in healthy persons, and existing longitudinal work has relied on depression assessment at a single time point. Our sample include 556 participants (303 women and 253 men), aged 20 to 93 years (mean +/- standard deviation = 55.8 +/- 15.9 years) who completed the Center for Epidemiological Studies-Depression (CES-D) scale from one to eight times over 1 to 15 years. These BLSA participants later underwent high-resolution B-mode ultrasonography to assess IMT of the far wall of the common carotid artery. A subset of these participants (n = 68) underwent reassessment of IMT an average of 3.9 years later. Linear and mixed-effects regression models were adjusted for sex, race, education, systolic blood pressure, low-density lipoprotein cholesterol, body mass index, diabetes, smoking, and antihypertensive, lipid-lowering, and antidepressant medications. We found no relation between trajectory of depressive symptoms or history of significant depressive symptoms and future carotid IMT. There was also no evidence for longitudinal covariation of depressive symptoms and IMT over time. Additional analyses similarly revealed a lack of significant associations. There is no association between depressive symptoms and carotid IMT in the present sample of healthy community-dwelling volunteers.