The Frequency of Anti-GAD Antibody in Non-obese, Adult-onset Type 2 Diabetes in Korea and Clinical and Biological Characteristics According to Anti-GAD Antibody

Background: Some of the characteristic features of diabetes mellitus in Korea are that 70-80% of patients are non-obese or adult-onset type, and type 1 diabetes is very rare. Occasionally, autoantibodies to glutamic acid decarboxylase(GAD) are found in typical, type 2 diabetes mellitus patients(T2DM). The role of the autoantibody to GAD in T2DM is unknown. The aim of this study was to determine the clinical and biochemical characteristics between GAD-positive and GAD-negative non-obese, adult-onset diabetics in Korea. Methods: A cohort of 428 type 2 diabetes patients was included. The measured autoantibodies to GAD were measured, and the C-peptide and HbA1c levels, anthropometric data(weight, height, body mass index and waist circumference), blood pressure and lipid profiles compared between the two groups. Results: Compared to the antibody-negative group(n=374; 87.4%), patients with the anti-GAD antibody(n=54; 12.6%) had significantly lower C-peptide levels and were significantly younger. The anti GAD-positive group had a lower BMI, more frequently needed insulin supplements, and a lower prevalence of hypertension. There were no significant differences in gender and family history of diabetes between the two groups. Conclusion: The presence of the autoantibody to GAD allowed the group with more deteriorated beta-cell function and more frequent need for insulin supplements, but a lower prevalence of obesity and hypertension to be determined.ope