FASTING PLASMA C-PEPTIDE LEVEL PREDICTS THE RESPONSE OF GLUCAGON-LIKE PEPTIDE-1 AGONIST (EXENATIDE) ADD ON TO METFORMIN MONOTHERAPY IN OBESE TYPE 2 DIABETICS

Abstract

Fasting Plasma C-peptide Level Predicts the Response of Glucagon-like Peptide-1 Agonist (Exenatide) Addition to Metformin Monotherapy in Obese Type 2 Diabetics ABSTRACT Aim: to evaluate the predictive ability of serum C-peptide level to attain glycemic control targets by adding a glucagon-like peptide-1 receptor agonist (GLP1-RA) to metformin monotherapy in patients with type 2 diabetes and obesity. Materials and methods: This is a retrospective study, in which we enrolled 44 consecutive obese type 2 diabetic patients who were on metformin monotherapy and have inadequate glycemic control (HbA1c >7% and <10%). Twice daily GLP1-RA (10 mcg exenatide injection) was added to the treatment. Regardless of the initial HbA1c level, treatment success was considered as an HbA1c level below 7%. Results: When we compared the initial and the sixth month measurements of body weight, BMI, fasting glucose and c-peptide, we found a reduction for all parameters (p<0.01). 27 (61.4%) patients were achieved treatment success. Baseline C-peptide level was correlated with HbA1c at sixth month (r:0.4, p:0.01). Baseline fasting plasma c-peptide level was an independent predictor of successful glycemic control [exp.B: 6.6 (1.63-26-9) p:0.008]. Baseline plasma C-peptide level of 2.56 ng/mL was the best cut-off value for prediction of treatment success. Conclusion: Initial fasting plasma c-peptide level can predict the treatment response of the GLP1-RA add on to metformin monotherapy in obese type 2 diabetics. Keywords: C-peptide, type 2 diabetes, GLP-1 RA, exenatide

Keywords

• C peptide
• Diabetes
• Obesity
• GLP-1 receptor agonist
• Exenatide

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