Serum insulin assay: an important therapeutic tool in management of freshly diagnosed type 2 diabetes mellitus.

OBJECTIVES: The study was performed to see that, whether metabolic control and response to treatment in freshly diagnosed patients of type 2 diabetes mellitus is affected by primary pathology (hyperinsulinemia/inappropriate insulin secretion).

METHODS: One hundred and eight freshly diagnosed patients of type 2 diabetes mellitus with age range from 30-65 years were followed for a period of three months. The blood glucose, serum triglyceride, and serum insulin levels were determined in each patient. Patients were found to have either higher or normal to low serum insulin values at fasting, and accordingly patients were distributed into two groups; group one (normal to low initial fasting serum insulin level i.e. < or = 30 microU/ml) and group two (high fasting serum insulin level i.e. > or = 30 microU/ml). Each group was further divided into two subgroups A and B. Subgroup A was treated with glipizide and B with metformin.

RESULTS: Diabetic patients who had fasting hyperinsulinemia (n = 53, 100%) had blood pressure > or = 140/90 at the time of presentation. Patients who had fasting serum insulin within normal range only 30% (n = 17) had hypertension. Patients of group one had good recovery from hyperglycemia and reduction in triglyceride values when treated with sulphonylurea (subgroup A) as compared to patients treated with biguanide (subgroup B). On the contrary patients of group two showed poor glycemic control, increase in blood pressure and rise in serum triglyceride titre when treated with sulphonylurea (subgroup A) while in the same group biguanide effectively produced euglycemia with normalization of blood pressure and decrease in triglyceride levels (subgroup B).

CONCLUSION: Assessment of initial serum insulin levels is helpful guide to decide about the type of oral hypoglycemic agent to be used in freshly diagnosed patients to type 2 diabetes mellitus.