Department of Neurology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Department of Epidemiology and Health Statistics, School of Public Health, Xi'an Jiaotong University Health Science Center, Xi'an, China.
Neuroepidemiology. 2023;57(2):100-111. doi: 10.1159/000527444. Epub 2022 Oct 13.
The relationship between obesity and cognitive impairment (CI) is highly heterogeneous in previous studies, which may be due to insufficient consideration of anthropometric indicators and sex. This study compared the cross-sectional relationships among body mass index (BMI), waist-to-hip ratio (WHR), and CI among people aged ≥40 years, and sex-specific relationships were also considered.
This was a population-based cross-sectional study with a cluster sampling design. CI was defined as a Mini-Mental State Examination score lower than the cutoff value. Multivariate logistic regression was used. BMI and WHR were fitted as both restricted cubic splines and categorical data. Stratified analysis and interaction analysis were performed to explore the sex-specific relationship.
A total of 1,792 subjects (40.5% male) were analyzed, and 230 were confirmed to have CI. The relationships among BMI, WHR, and CI were significant (poverall = 0.023, pnonlinear = 0.097; poverall = 0.017, pnonlinear = 0.078, respectively) but exhibited an opposite trend in the total population in the analyses with BMI and WHR as restricted cubic splines. Further categorical analyses showed that subjects with a BMI <23 kg/m2 tended to have a higher risk of CI than those with BMI ≥23 kg/m2 (16.2% vs. 11.8%, p = 0.017; OR = 1.366 [0.969-1.926], p = 0.075), and subjects with a WHR >0.92 had a significantly higher risk of CI than those with a WHR ≤0.92 (11.7% vs. 16.2%, p = 0.011; OR = 1.619 [1.161-2.258], p = 0.005). In addition, the relationship between a low BMI and CI was more significant in males (p = 0.034), while the relationship between a high WHR and CI was more significant in females (p = 0.002). Further studies are needed to confirm the sex differences because of the marginal significance result in the interaction analysis (p = 0.051 for interaction term BMI × sex; p = 0.056 for interaction term WHR × sex).
The relationships among BMI, WHR, and CI exhibit an opposite trend. A low BMI or high WHR was positively associated with CI, which was more prominent in males for a low BMI and females for a high WHR.
肥胖与认知障碍（CI）之间的关系在以往的研究中差异较大，这可能是由于对人体测量指标和性别考虑不足。本研究比较了≥40 岁人群中体重指数（BMI）、腰臀比（WHR）与 CI 之间的横断面关系，并考虑了性别特异性关系。
这是一项基于人群的横断面研究，采用聚类抽样设计。CI 定义为简易精神状态检查评分低于截断值。采用多变量逻辑回归。BMI 和 WHR 均采用限制立方样条和分类数据拟合。进行分层分析和交互分析以探讨性别特异性关系。
共分析了 1792 名受试者（40.5%为男性），其中 230 名被确诊为 CI。BMI、WHR 和 CI 之间的关系具有统计学意义（p 总体=0.023，p 非线性=0.097；p 总体=0.017，p 非线性=0.078），但在 BMI 和 WHR 作为限制立方样条的分析中，总体人群的关系呈相反趋势。进一步的分类分析显示，BMI<23kg/m2 的受试者发生 CI 的风险高于 BMI≥23kg/m2 的受试者（16.2% vs. 11.8%，p=0.017；OR=1.366[0.969-1.926]，p=0.075），WHR>0.92 的受试者发生 CI 的风险明显高于 WHR≤0.92 的受试者（11.7% vs. 16.2%，p=0.011；OR=1.619[1.161-2.258]，p=0.005）。此外，低 BMI 与 CI 之间的关系在男性中更为显著（p=0.034），而高 WHR 与 CI 之间的关系在女性中更为显著（p=0.002）。由于交互分析的边际显著性结果（BMI×性别交互项 p=0.051；WHR×性别交互项 p=0.056），需要进一步的研究来证实性别差异。
BMI、WHR 和 CI 之间的关系呈相反趋势。低 BMI 或高 WHR 与 CI 呈正相关，低 BMI 与男性 CI 关系更显著，高 WHR 与女性 CI 关系更显著。
