LADA和2型糖尿病一级亲属胰岛β细胞功能的变化

Islet beta cell function in first-degree relatives of probands with LADA and with type 2 diabetes

目的探讨成人隐匿性自身免疫性糖尿病(LADA)和2型糖尿病(T2DM)一级亲属胰岛β细胞功能的变化。方法对24例健康对照(NC)、28例谷氨酸脱羧酶抗体(GADAb)阳性LADA一级亲属、14例羧基肽酶H抗体(CPHAb)阳性LADA一级亲属、15例T2DM一级亲属行纳格列奈OGTT,比较其反映β细胞功能的相关指标。结果①GADAb阳性LADA一级亲属的胰岛素释放峰值、30min时的△I/△G、IRR、MVI、AUCIns较NC组降低(P<0.05～0.01);其HOMAIR高于NC组(P<0.05);②T2DM一级亲属组的HOMAIR高于NC组(P<0.05);③LADA一级亲属组中抗体阳性者的胰岛素释放峰值、30min时的△I/△G、IRR及MVI较阴性者降低更明显;后者的HOMAIR大于NC组(P<0.05)。结论LADA一级亲属存在明显的早期相胰岛分泌与储备功能减退及IR,其中抗体阳性者以胰岛分泌功能缺陷为主伴IR,抗体阴性者以IR为主伴胰岛分泌功能缺陷;T2DM一级亲属存在明显的IR。

Objective To assess islet beta-cell function in non-diabetic first-degree relatives of LADA and T2DM. Methods Nateglinide（NG）-OGTT was performed in 24 healthy volunteers, 28 first-degree relatives of LADA with GAD-Ab, 14 with CPH-Ab, 15 first-degree relatives of T2DM. Results （1） During NG-OGTT, the insulin release peak value, ΔI30min/ΔG30min, IRR30min, MVI and AUCIns30 min were decreased by 30.23%,44.86%,37.55%,51.19% and 25.12% （P〈0. 05-0.01） respectively and the HOMA-IR was higher（P〈0.05） in first-degree relatives of LADA with GAD-Ab than in controls. （2）The HOMA-IR was higher（P〈0.05）in first-degree relatives of T2DM than in control. （3） The insulin release peak value, ΔI30min/ΔG30min, IRR30min and MVI were 44.81% and 17.28%,43.93%and 43.46%, 49.28% and 29.50% ,59.00% and 34.70% lower（P〈0. 05-0. 01） respectively in first-degree relatives with and without islet autoantibodies than in controls. The HOMA-IR was higher（P〈0. 05） in first-degree relatives without islet autoantibodies. Conclusions Besides the obvious decrease of the early insulin release and maximally stimulated beta-cell capacity, there also exists IR in first-degree relatives of LADA. There exists serious IR in first-degree relatives of T2DM. In first-degree relatives with islet autoantibodies, the change in islet beta-cell function mainly involves early insulin release impairment with some IR as well.