Comparing C-peptide and HbA1c levels in obese patients with and without type 2 diabetes

N. Sridevi; N. Chowdeswari; A. Navaneeta Lakshmi; P. Madhusudhan; N. Kirmani; Rakesh Anil; Shyam Sundar Kumar

doi:10.18203/2320-6012.ijrms20262631

Authors

N. Sridevi Government Medical College, Vijaywada, Andhra Pradesh, India
N. Chowdeswari Government Medical College, Vijaywada, Andhra Pradesh, India
A. Navaneeta Lakshmi Government Medical College, Vijaywada, Andhra Pradesh, India
P. Madhusudhan Government Medical College, Vijaywada, Andhra Pradesh, India
N. Kirmani Government Medical College, Vijaywada, Andhra Pradesh, India
Rakesh Anil Government Medical College, Vijaywada, Andhra Pradesh, India
Shyam Sundar Kumar Government Medical College, Vijaywada, Andhra Pradesh, India

DOI:

https://doi.org/10.18203/2320-6012.ijrms20262631

Keywords:

Obesity, HbA1c, C-Peptide, Diabetics, Non-diabetics, Insulin resistance

Abstract

Background: Diabetes mellitus (DM) is a chronic metabolic disorder characterized by either insufficient insulin production by the pancreas or the body's inability to utilize it. HbA1c level of 6.5% was recommended for diagnosing diabetes. C-peptide is a byproduct of insulin synthesis has been widely studied as a diagnostic biomarker for DM. Obesity is a major risk factor for the development of type 2 DM (T2DM) and is associated with insulin resistance. With the increasing global burden of obesity and diabetes, our study investigates the relationship between HbA1c and C-peptide levels in obese individuals with and without diabetes. Objectives were to assess and compare HbA1c and C-peptide levels among obese individuals with diabetes and without diabetes and to evaluate the correlation between these parameters within each group.

Methods: This study was included 30 obese diabetic and 30 obese non-diabetic participants recruited over 3 months. Blood samples were collected for estimating HbA1c and C-peptide. Ethical approval was obtained prior to the study. Data were analyzed using Jamovi software.

Results: HbA1c and C-peptide levels were significantly higher in obese individuals with diabetes compared to non-diabetic obese controls (p<0.001). A strong positive correlation was observed between HbA1c and C-peptide levels in both groups, with a stronger association in diabetics (r=0.94) compared to non-diabetics (r=0.88); both correlations were statistically significant.

Conclusions: Higher levels and strong positive correlation between HbA1c and C-peptide-especially in diabetics-suggests increased insulin secretion in response to poor glycemic control and insulin resistance.

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