C-Peptide levels as a screening marker for initiating insulin therapy in type 2 diabetics.

Abstract

Objectives: Serum C-peptide is identified as an indicator of insulin secretion and a useful marker of beta-cell function. Clinically C-peptide is a good indicator in differentiating between type 1 and type 2 diabetes. It is the more reliable indicator of insulin secretion and beta cell function than insulin itself. In liver during first pass metabolism half of the insulin is metabolized however the hepatic clearance of C-peptide is negligible. The purpose of this study was to explore the probability of C-peptide level as an indicator or screening for initiating insulin therapy in type 2 diabetics. Study Design: Cross sectional descriptive study. Setting: The study was conducted in attached teaching hospitals Peshawar Medical College. Period: From February 2017 to July 2017. Material and Method: In the present study 45 type 2 diabetic patients were selected from the admitted patients and patients visiting outpatient departments of Mercy and Kuwait teaching Hospitals as per the inclusion and exclusion criteria and were compared with 45 non diabetic controls. Results: A total of ninety subjects who fulfilled the inclusion criteria participated in this study. Out of them 45 were diabetics (cases) and 45 were non diabetics (controls). The mean HbA1c levels of controls was 5.351±0.57% and mean among type 2 diabetics was 8.6± 1.7%. The mean of C-peptide among type 2 diabetics is 2.349± 0.73 and the mean value of C-peptide among controls is 2.529±1.060. Patients with HbA1c of 5.5-6.8 % (Good Control), 8 patients have C-peptide in lower normal range 0.1-2 ng/mL, among patients with HbA1c of 6.9-7.6% (Fair Control), 5 patients had C-peptide in the lower normal range 0.1-2 ng/ mL and among patients with HbA1c › 7.6 (Uncontrolled), 2 had C peptide in lower normal range and 30 patients had C-peptide in the upper normal range 2.1-4 ng/ mL. In our study population the type 2 diabetics have C-peptide levels in normal range. Most of the type 2 diabetics have uncontrolled diabetes as evident from their high HbA1c levels but their C-peptide levels are in upper normal ranges. This shows that these patients have intact beta cell function and the cause of their uncontrolled diabetes may be insulin resistance, poor drug compliance and lack of awareness about the disease management. To explore the probability of C-peptide level as an indicator or screening for initiating insulin therapy in type 2 diabetics. Conclusion: It is concluded that C-peptide is not a useful marker for starting insulin therapy in type 2 diabetics. However it can be used for the clinical monitoring and management of the disease.