Howard G, O'Leary D H, Zaccaro D, Haffner S, Rewers M, Hamman R, Selby J V, Saad M F, Savage P, Bergman R
Department of Public Health Sciences, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, NC 27157-1063, USA.
Circulation. 1996 May 15;93(10):1809-17. doi: 10.1161/01.cir.93.10.1809.
Reduced insulin sensitivity has been proposed as an important risk factor in the development of atherosclerosis. However, insulin sensitivity is related to many other cardiovascular risk factors, including plasma insulin levels, and it is unclear whether an independent role of insulin sensitivity exists. Large epidemiological studies that measure insulin sensitivity directly have not been conducted.
The Insulin Resistance Atherosclerosis Study (IRAS) evaluated insulin sensitivity (SI) by the frequently sampled intravenous glucose tolerance test with analysis by the minimal model of Bergman. IRAS measured intimal-medial thickness (IMT) of the carotid artery as an index of atherosclerosis by use of noninvasive B-mode ultrasonography. These measures, as well as factors that may potentially confound or mediate the relationship between insulin sensitivity and atherosclerosis, were available in relation to 398 black, 457 Hispanic, and 542 non-Hispanic white IRAS participants. There was a significant negative association between SI and the IMT of the carotid artery both in Hispanics and in non-Hispanic whites. This effect was reduced but not totally explained by adjustment for traditional cardiovascular disease risk factors, glucose tolerance, measures of adiposity, and fasting insulin levels. There was no association between SI and the IMT of the carotid artery in blacks. The association between SI and the IMT was stronger for the internal carotid artery than for the common carotid artery in all ethnic groups.
Higher levels of insulin sensitivity are associated with less atherosclerosis in Hispanics and non-Hispanic whites but not in blacks. This effect is partially mediated by traditional cardiovascular risk factors.
胰岛素敏感性降低被认为是动脉粥样硬化发生发展的一个重要危险因素。然而，胰岛素敏感性与许多其他心血管危险因素相关，包括血浆胰岛素水平，目前尚不清楚胰岛素敏感性是否具有独立作用。尚未开展直接测量胰岛素敏感性的大型流行病学研究。
胰岛素抵抗动脉粥样硬化研究（IRAS）通过频繁采样静脉葡萄糖耐量试验并采用伯格曼最小模型进行分析来评估胰岛素敏感性（SI）。IRAS使用无创B型超声测量颈动脉内膜中层厚度（IMT）作为动脉粥样硬化的指标。这些测量指标以及可能混淆或介导胰岛素敏感性与动脉粥样硬化之间关系的因素，可用于398名黑人、457名西班牙裔和542名非西班牙裔白人IRAS参与者。在西班牙裔和非西班牙裔白人中，SI与颈动脉IMT之间均存在显著的负相关。通过调整传统心血管疾病危险因素、糖耐量、肥胖指标和空腹胰岛素水平后，这种效应有所减弱，但并未完全消除。在黑人中，SI与颈动脉IMT之间无关联。在所有种族中，SI与颈动脉IMT之间的关联在内颈动脉比在颈总动脉更强。
较高水平的胰岛素敏感性与西班牙裔和非西班牙裔白人中较少的动脉粥样硬化相关，但与黑人无关。这种效应部分由传统心血管危险因素介导。
