Qu Chunmei, Zhou Xiaoxin, Yang Gangyi, Li Ling, Liu Hua, Liang Zerong
Department of Endocrinology, Chongqing Red Cross Hospital (People's Hospital of Jiangbei District), Chongqing 400020, China.
Department of Endocrinology, The Second Affiliated Hospital Chongqing Medical University, Chongqing 400010, China.
Cytokine. 2016 Mar;79:96-102. doi: 10.1016/j.cyto.2015.12.024. Epub 2016 Jan 12.
The euglycemic-hyperinsulinemic clamp (EHC) is not available in most clinical settings and is costly, time consuming and invasive, and requires trained staff. Therefore, an accessible and inexpensive test to identify insulin resistance (IR) is needed. The aim of this study is to assess whether zinc-α2-glycoprotein (ZAG) index [Ln ZAG/homeostasis model assessment of IR (HOMA-IR)] is a better surrogate index for estimating IR or metabolic syndrome (MetS) compared with other surrogate indices.
We performed a population-based cross-sectional study. Two hundred healthy subjects, 102 polycystic ovary syndrome (PCOS) patients, 97 newly diagnosed type 2 diabetes mellitus (nT2DM) and 84 impaired glucose tolerance (IGT) subjects were enrolled. The EHC was performed to identify IR. Circulating ZAG and adiponectin levels were determined by ELISA.
The ZAG index was significantly lower in participants with IR including IGT, nT2DM and PCOS than in those without IR. In addition, subjects with MetS had lower ZAG indices and higher the product of fasting triglycerides and glucose (TyG) indices than those without MetS. The ZAG index showed a significantly stronger association with M values than the other surrogate indices, whereas the TyG index showed a stronger association with MetS. The optimal cutoff value of the ZAG index for detection of IR was 2.97 with a sensitivity of 88% and a specificity of 91%, whereas the optimal cutoff value of TyG index for detection of MetS was 4.90 with a sensitivity of 82% and a specificity of 86%.
The ZAG index is a better marker than the other surrogate indices for identifying IR, whereas the TyG index has high sensitivity and specificity for identifying MetS.
多数临床环境中无法开展正常血糖-高胰岛素钳夹试验（EHC），该试验成本高、耗时且具有侵入性，还需要专业人员操作。因此，需要一种便捷且经济的检测方法来识别胰岛素抵抗（IR）。本研究旨在评估锌-α2-糖蛋白（ZAG）指数[Ln ZAG/胰岛素抵抗稳态模型评估（HOMA-IR）]与其他替代指标相比，是否为评估IR或代谢综合征（MetS）的更好替代指标。
我们开展了一项基于人群的横断面研究。纳入了200名健康受试者、102名多囊卵巢综合征（PCOS）患者、97名新诊断的2型糖尿病（nT2DM）患者和84名糖耐量受损（IGT）受试者。通过EHC来识别IR。采用酶联免疫吸附测定法（ELISA）测定循环ZAG和脂联素水平。
包括IGT、nT2DM和PCOS在内的IR参与者的ZAG指数显著低于无IR者。此外，与无MetS者相比，MetS患者的ZAG指数更低，空腹甘油三酯与血糖乘积（TyG）指数更高。与其他替代指标相比，ZAG指数与M值的相关性显著更强，而TyG指数与MetS的相关性更强。检测IR时ZAG指数的最佳截断值为2.97，灵敏度为88%，特异度为91%；而检测MetS时TyG指数的最佳截断值为4.90，灵敏度为82%，特异度为86%。
ZAG指数是比其他替代指标更好的识别IR的标志物，而TyG指数在识别MetS方面具有高灵敏度和特异度。
