Clinical Endocrinology Branch, National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health, Bethesda, Maryland 0892-1612, USA.
Metab Syndr Relat Disord. 2010 Dec;8(6):511-4. doi: 10.1089/met.2010.0028. Epub 2010 Aug 17.
Compared to whites, insulin-resistant African Americans have worse outcomes. Screening programs that could identify insulin resistance early enough for intervention to affect outcome often rely on triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C) levels. Racial differences in TG and HDL-C may compromise the efficacy of these programs in African Americans. A recommendation currently exists to use the TG/HDL-C ratio ≥2.0 to predict insulin resistance in African Americans. The validity of this recommendation needs examination. Therefore, our aim was to determine the ability of TG/HDL-C ratio to predict insulin resistance in African Americans.
In 1,903 African Americans [895 men, 1,008 women, age 55 ± 12 years, mean ± standard deviation (SD), range 35-80 years, body mass index (BMI) 31.0 ± 6.4 kg/m(2), range 18.5-55 kg/m(2)] participating in the Jackson Heart Study, a population-based study of African Americans, Jackson, Mississippi tricounty region, insulin resistance was defined by the upper quartile (≥4.43) of homeostasis model assessment of insulin resistance (HOMA-IR). An area under the receiver operating characteristic curve (AUC-ROC) of >0.70 was required for prediction of insulin resistance by TG/HDL-C. The optimal test cutoff was determined by the Youden index.
HOMA-IR was similar in men and women (3.40 ± 2.03 vs. 3.80 ± 2.46, P = 0.60). Women had lower TG (94 ± 49 vs. 109 ± 65 mg/dL P < 0.001) and TG/HDL-C (1.9 ± 1.4 vs. 2.7 ± 2.1, P < 0.001). For men, AUC-ROC for prediction of insulin resistance by TG/HDL-C was: 0.77 ± 0.01, mean ± standard error (SE), with an optimal cutoff of ≥2.5. For women, the AUC-ROC was 0.66 ± 0.01, rendering an optimal cutoff indefinable. When women were divided in two groups according to age, 35-50 years and 51-80 years, the results did not change.
In African-American men, the recommended TG/HDL-C threshold of 2.0 should be adjusted upward to 2.5. In African-American women, TG/HDL-C cannot identify insulin resistance. The Jackson Heart Study can help determine the efficacy of screening programs in African-Americans.
与白人相比，胰岛素抵抗的非裔美国人的预后更差。能够及早发现胰岛素抵抗并进行干预以改善预后的筛查方案，通常依赖于甘油三酯（TG）和高密度脂蛋白胆固醇（HDL-C）水平。TG 和 HDL-C 水平的种族差异可能会影响这些方案在非裔美国人中的效果。目前有一项建议使用 TG/HDL-C 比值≥2.0 来预测非裔美国人的胰岛素抵抗。该建议的有效性需要进行检查。因此，我们的目的是确定 TG/HDL-C 比值预测非裔美国人胰岛素抵抗的能力。
在 1903 名非裔美国人（895 名男性，1008 名女性，年龄 55±12 岁，均值±标准差，范围 35-80 岁，体重指数[BMI]31.0±6.4kg/m²，范围 18.5-55kg/m²）中，我们进行了一项基于人群的非裔美国人研究——密西西比州杰克逊心脏研究，其中胰岛素抵抗定义为稳态模型评估的胰岛素抵抗（HOMA-IR）的四分位上限（≥4.43）。需要 TG/HDL-C 的接收者操作特征曲线（ROC）下面积（AUC-ROC）>0.70 来预测胰岛素抵抗。通过约登指数确定最佳测试截止值。
男性和女性的 HOMA-IR 相似（3.40±2.03 与 3.80±2.46，P=0.60）。女性的 TG（94±49 与 109±65mg/dL，P<0.001）和 TG/HDL-C（1.9±1.4 与 2.7±2.1，P<0.001）水平较低。对于男性，TG/HDL-C 预测胰岛素抵抗的 AUC-ROC 为：0.77±0.01，均值±标准误（SE），最佳截断值为≥2.5。对于女性，AUC-ROC 为 0.66±0.01，使得最佳截断值无法确定。当根据年龄将女性分为 35-50 岁和 51-80 岁两组时，结果没有改变。
在非裔美国男性中，建议的 TG/HDL-C 阈值 2.0 应上调至 2.5。在非裔美国女性中，TG/HDL-C 无法识别胰岛素抵抗。杰克逊心脏研究可以帮助确定在非裔美国人中筛查方案的效果。
