Department of Medicine, Division of Geriatrics, University of Mississippi Medical Center, Jackson.
Department of Data Science, University of Mississippi Medical Center, Jackson.
J Gerontol A Biol Sci Med Sci. 2018 Mar 14;73(4):492-498. doi: 10.1093/gerona/glx163.
Adiposity depots may differentially affect cognition. African Americans (AA) have higher rates of obesity and dementia but lower visceral adipose tissue (VAT) than whites, yet are underrepresented in studies of adiposity and cognition. Our study compared relations of cognitive function to clinical adiposity measures and computed tomography (CT)-imaged abdominal adiposity in AA.
CT-imaged subcutaneous adipose tissue (SAT) and VAT measurements were obtained in the AA cohort of the Genetic Epidemiology Network of Arteriopathy Study (N = 652, mean age 68 ± 8.4 years, 74% females, 59% obese, 82% hypertensive). Clinical adiposity measures included waist circumference (WC) and body mass index (BMI). Global cognition was operationalized as a global cognitive z-score generated from the average of four cognitive domain z-scores. Generalized estimating equations were used to examine cross-sectional associations between individual standardized adiposity measures and cognition, accounting for age, sex, education, smoking status, and familial clustering. A collective model was constructed including multiple supported adiposity measures and age-by-adiposity interactions.
In the collective model, higher WC was associated with worse global cognition, β = -0.12 (95%CI: -0.21, -0.03); higher SAT was associated with better cognition, β = 0.09 (0.01, 0.18); higher BMI was associated with worse cognition at younger ages with attenuation at older ages (BMI-by-age-interaction p = .004). VAT was not significantly associated with global cognition, β = -0.03 (-0.07, 0.02).
WC may be the simplest and most efficient measure of adiposity to assess with respect to cognition in clinical settings, although studies to determine mechanistic effects of subcutaneous and other adiposity depots on cognition are warranted.
脂肪组织可能会对认知能力产生不同的影响。非裔美国人（AA）的肥胖症和痴呆症发病率较高，而内脏脂肪组织（VAT）含量较低，但在肥胖症和认知能力研究中代表性不足。我们的研究比较了 AA 人群认知功能与临床肥胖测量指标和计算机断层扫描（CT）成像腹部脂肪的关系。
在动脉粥样硬化遗传流行病学网络研究（N=652，平均年龄 68±8.4 岁，74%为女性，59%为肥胖，82%为高血压）的 AA 队列中获得 CT 成像皮下脂肪组织（SAT）和 VAT 测量值。临床肥胖测量指标包括腰围（WC）和体重指数（BMI）。整体认知功能通过四个认知域 z 分数平均值生成的整体认知 z 分数来进行操作。广义估计方程用于检查个体标准化肥胖测量指标与认知之间的横断面关联，同时考虑年龄、性别、教育、吸烟状况和家族聚集性。构建了一个包含多个支持的肥胖测量指标和年龄与肥胖相互作用的综合模型。
在综合模型中，WC 越高与整体认知能力越差相关，β=-0.12（95%CI：-0.21，-0.03）；SAT 越高与认知能力越好相关，β=0.09（0.01，0.18）；BMI 与较年轻人群的认知能力较差相关，随着年龄的增长而减弱（BMI-年龄交互作用 p=0.004）。VAT 与整体认知能力无显著相关性，β=-0.03（-0.07，0.02）。
WC 可能是评估临床环境中认知能力最简单、最有效的肥胖测量指标，尽管需要进一步研究以确定皮下和其他脂肪组织对认知的机制影响。
