Follow-up study on islet autoantibodies of gestational diabetes mellitus / 中国医师进修杂志

ABSTRACT

Objective To investigate the role ofglutamic acid decarboxylase autoantibody(GAD-Ab)and protein tyrosine phosphatase autoantibody(IA-2A) in postpartum follow-up of gestational diabetes mellitus (GDM).MethodsGAD-Ab,IA-2A,insulin and glucose metabolism index were measured in 82subjects with normal glucose tolerance (control group) and 84 patients with GDM(GDM group) during 24 to 28 weeks in pregnancy,postpartum 6 to 12 weeks and 2 years.GDM group was divided into antibodies positive group (GAD-Ah or IA-2A were positive) with 18 cases and antibodies negative group (GAD-Ab and IA-2A was negative) with 66 cases.Results Homeostasis model insulin resistance index (HOMA-IR) in GDM group was higher than that in control group (3.87 ± 2.17 vs.2.31 ± 0.52,P ＜ 0.05 ).Homeostasis β -cell function index (HBCI) and 30 min net increment of insulin/30 min net increment of glucose ( △ I30/△ G30) in GDM group were lower than those in control group[206.38 ± 138.06 vs.422.43 ± 228.93 and (20.16 ±11.38) mU/mmol vs.(26.54 ±24.30) mU/mmol,P ＜0.05].The numbers who had the family history of diabetes mellitus and the used of insulin for treatment in antibodies positive group were higher than those in antibodies negative group[ 83.3％ (15/18) vs.28.8％ (19/66) and 77.8％ ( 14/18 ) vs.30.3％ (20/66) ],HOMA-IR,△ I30/ △ G30 and HBCI in antibodies positive group were lower than those in antibodies negative group [3.20±0.84 vs.4.02±0.36,(16.81 ±2.91) mU/mmol vs.(21.55± 11.11) mU/mmol and 124.95 ± 5.03 vs.217.43 ± 115.64,P＜ 0.01 ].Fasting plasma glucose (FPG),2 hours postprandial glucose (2hPG)and glycosylated hemoglobin (HbA1c) in antibodies positive group were higher than those in antibodies negative group during postpartum 6 to 12 weeks and 2 years [postpartum 6 to 12 weeks (8.20 ±3.11)mmol/L vs.(5.39 ±0.76) mmol/L,(15.22 ±7.29) mmol/L vs.(8.15 ± 1.93) mmol/L,(7.26 ± 1.04)％ vs.(5.88 ±0.41)％ ;postpartum 2 years (8.91 ±2.80) mmol/L vs.(4.93 ±0.66) mmol/L,(15.75 ±7.87)mmol/L vs.(7.85 ± 1.79) mtmol/L,(7.18 ± 1.22)％ vs.(5.64 ± 0.32 )％,P ＜ 0.01].△ I30/ △ G30 and HBCI were significantly decreased in antibodies positive group postpartum 2 years.No change of the above parameters in antibodies negative group was found.The occurrence rate of type 1 diabetes mellitus (T1DM) was 16.7％(3/18) and 33.3％(6/18) postpartum 6 to 12 weeks and 2 years in antibodies positive group,there was no T1DM in antibodies negative group.ConclusionsWomen with GDM are partly associated with T1DM.Requiring insulin therapy during pregnancy and GAD-Ab or IA-2A positive have considerable risk for developing T1DM.It is also an important predictor to GDM after parturition.