Abstract

BACKGROUND
Secondary failure of oral hypoglycemic agents is defined as that blood glucose is no longer controlled with sulfonylurea after a proven period of good glycemic control. There are many causes of secondary failure, including that drug problem, acute illnesses, inappropriate drug dosages, oxidative stress & glucose toxicity of beta-cell, etc. And many studies have suggested role of immunologic process such as islet cell antibody (ICA) and/or glutamic acid decarboxylase antibody (GADA) for the causes of secondary failure. So we evaluated the prevalence of ICA & GADA in type 2 diabetes with secondary failure of oral hypoglycemic agents and the pathogenesis of the secondary failure. METHODS: We studied 267 patients with type 2 diabetes. We regarded 84 patients who could not control HbA1c less than 8% after good glycemic control for at least 1 year as secondary failure group (group 1) and regarded the other 183 patients as group 2. We measured GADA in both group, and measured the prevalence of GADA and ICA in secondary failure group who were especially divided into obese group and nonobese group according to BMI and were divided into insulin deficiency group and noninsulin deficiency group according to fasting C-peptide level. RESULTS: The prevalence of GADA in all subjects was 4.1%, which was 9.5% in group 1 and 1.6% in group 2 (P < 0.05). Among 35 patients of the group 1 who could be checked ICA, the prevalence of GADA & ICA were 33% & 25% in insulin deficiency group and 4.3% & 0% in non-insulin deficiency group, respectively (P < 0.05). The prevalence of GADA & ICA were none in obese group and 33.3% & 20% in nonobese group, respectively (P < 0.05). The prevalence of GADA & ICA were 36.4% & 27.3% in nonobese and insulin deficiency, 4.2% & 0% in obese and non-insulin deficiency. CONCLUSION: We suggest that autoimmune mechanism is associated with increased risk for secondary failure of oral hypoglycemic agents in type 2 diabetes, so the measurement of GADA and ICA could help to predict the potential risk and insulin treatment.

• Keywords: GADA;ICA;Oral hypoglycemic therapy;Secondary failure;