Larner College of Medicine at the University of Vermont, Burlington, VT, USA.
Department of Biostatistics, School of Public Health, University of Alabama at Birmingham, Birmingham, AL, USA.
J Clin Endocrinol Metab. 2022 May 17;107(6):e2523-e2531. doi: 10.1210/clinem/dgac074.
Black adults experience more type 2 diabetes mellitus and higher inflammatory markers, including C-reactive protein (CRP), than White adults. Inflammatory markers are associated with risk of incident diabetes but the impact of inflammation on racial differences in incident diabetes is unknown.
We assessed whether CRP mediated the Black-White incident diabetes disparity.
The REasons for Geographic And Racial Differences in Stroke (REGARDS) study enrolled 30 239 US Black and White adults aged ≥45 years in 2003-2007 with a second visit approximately 10 years later. Among participants without baseline diabetes, adjusted sex- and race-stratified risk ratios for incident diabetes at the second visit by CRP level were calculated using modified Poisson regression. Inverse odds weighting estimated the percent mediation of the racial disparity by CRP.
Of 11 073 participants without baseline diabetes (33% Black, 67% White), 1389 (12.5%) developed diabetes. Black participants had higher CRP at baseline and greater incident diabetes than White participants. Relative to CRP < 3 mg/L, CRP ≥ 3 mg/L was associated with greater risk of diabetes in all race-sex strata. Black participants had higher risk of diabetes at CRP < 3 mg/L, but not at CRP ≥ 3 mg/L. In women, CRP mediated 10.0% of the racial difference in incident diabetes. This mediation was not seen in men.
Higher CRP is a risk factor for incident diabetes, but the excess burden of diabetes in Black adults was only seen in those with lower CRP, suggesting that inflammation is unlikely to be the main driver of this racial disparity.
黑种成年人比白种成年人更容易患 2 型糖尿病和更高的炎症标志物，包括 C 反应蛋白（CRP）。炎症标志物与发生糖尿病的风险相关，但炎症对发生糖尿病的种族差异的影响尚不清楚。
我们评估了 CRP 是否介导了黑种人与白种人发生糖尿病的差异。
REasons for Geographic And Racial Differences in Stroke（REGARDS）研究在 2003 年至 2007 年间招募了 30239 名年龄在 45 岁及以上的美国黑人和白人成年人，他们在大约 10 年后进行了第二次访问。在没有基线糖尿病的参与者中，使用修正泊松回归计算了第二次访问时按 CRP 水平分层的调整后的性别和种族分层的糖尿病发生率的风险比。逆概率加权估计了 CRP 对种族差异的中介百分比。
在 11073 名没有基线糖尿病（33%为黑人，67%为白人）的参与者中，有 1389 名（12.5%）发生了糖尿病。黑人参与者的 CRP 基线水平较高，发生糖尿病的比例也高于白人参与者。与 CRP<3mg/L 相比，CRP≥3mg/L 在所有种族和性别分层中都与糖尿病风险增加相关。黑人参与者在 CRP<3mg/L 时发生糖尿病的风险较高，但在 CRP≥3mg/L 时则不然。在女性中，CRP 介导了 10.0%的糖尿病发病的种族差异。在男性中则没有观察到这种中介作用。
较高的 CRP 是发生糖尿病的一个危险因素，但黑人成年人患糖尿病的负担增加仅见于 CRP 较低的人群，这表明炎症不太可能是导致这种种族差异的主要因素。
