Windham B Gwen, Lirette Seth T, Fornage Myriam, Benjamin Emelia J, Parker Kirby G, Turner Stephen T, Jack Clifford R, Griswold Michael E, Mosley Thomas H
Department of Medicine-Geriatrics, University of Mississippi Medical Center, Jackson.
Center of Biostatistics, Jackson, Mississippi.
J Gerontol A Biol Sci Med Sci. 2017 Jun 1;72(6):825-831. doi: 10.1093/gerona/glw239.
Studies of adiposity and brain pathology in African Americans (AA) are sparse despite higher rates of obesity, dementia, and dementia-associated brain pathology in AA. This study examined relations of adiposity to white matter hyperintensities (WMH) and total brain volume (TBV) in AA and non-Hispanic whites (NHW).
Waist circumference (WC) and body mass index (BMI) were measured in the Genetic Epidemiology Network of Arteriopathy study at Visits 1 (mean age 57 [±11]) and 2 (mean age 61 [±10], mean 5.2 years later). Brain MRIs were obtained shortly after Visit 2 in 1,702 participants (64% women, 48% AA). Multilevel linear regression using generalized estimating equation estimated associations of adiposity (cross-sectional) or adiposity changes with WMH (accounting for intracranial size) or TBV adjusting for demographics, cardiovascular risk factors, and incorporating adiposity-by-race interactions. Adiposity-by-age interactions were examined.
Concurrent TBV was inversely associated with BMI (β = -2.76 [95% confidence interval (CI): -4.99, -0.53]) and WC (β = -2.19 [CI: -4.04, -0.34]). Concurrent WMH were negatively associated with BMI (β = -0.04 [CI: -0.06, -0.01]) and, among NHW, with WC (β = -0.04 [CI: -0.06, -0.02]) but not with changes in BMI or WC. BMI increases were associated with lower TBV (β = -16.20, [CI: -30.34, -2.06]) in AA but not in NHW (β = -2.76 [CI: -14.02, 8.51]), although race-by-adiposity interactions were not supported. WC increases were not associated with MRI outcomes.
Greater measures of obesity and increases in measures of obesity, which are common in mid-life, could be detrimental to brain health, particularly in AA.
尽管非裔美国人（AA）的肥胖、痴呆及与痴呆相关的脑病理学发生率较高，但针对该群体肥胖与脑病理学的研究却较为匮乏。本研究调查了AA和非西班牙裔白人（NHW）中肥胖与白质高信号（WMH）及全脑体积（TBV）之间的关系。
在动脉病遗传流行病学网络研究的第1次访视（平均年龄57[±11]岁）和第2次访视（平均年龄61[±10]岁，平均间隔5.2年）时测量腰围（WC）和体重指数（BMI）。在第2次访视后不久，对1702名参与者（64%为女性，48%为AA）进行脑部MRI检查。使用广义估计方程的多水平线性回归估计肥胖（横断面）或肥胖变化与WMH（校正颅内大小）或TBV之间的关联，并对人口统计学、心血管危险因素进行校正，同时纳入肥胖与种族的交互作用。对肥胖与年龄的交互作用进行了研究。
同时期的TBV与BMI（β=-2.76[95%置信区间（CI）：-4.99，-0.53]）和WC（β=-2.19[CI：-4.04，-0.34]）呈负相关。同时期的WMH与BMI（β=-0.04[CI：-0.06，-0.01]）呈负相关，在NHW中与WC（β=-0.04[CI：-0.06，-0.02]）呈负相关，但与BMI或WC的变化无关。BMI增加与AA的TBV降低相关（β=-16.20，[CI：-30.34，-2.06]），但在NHW中不相关（β=-2.76[CI：-14.02，8.51]），尽管肥胖与种族的交互作用未得到支持。WC增加与MRI结果无关。
更大程度的肥胖测量值及肥胖测量值的增加在中年人群中很常见，可能对脑健康有害，尤其是在AA人群中。
