Serum C-Peptide Patterns and Metabolic Characteristics of Adults With Long-Standing Type 2 Diabetes
DOI:
https://doi.org/10.61336/jdme.0702.02Keywords:
C-peptide, type 2 diabetes, beta-cell function, insulin secretion, insulin resistance, long-standing diabetes, metabolic characteristicsAbstract
Progressive decline in pancreatic beta-cell function is an important feature of long-standing type 2 diabetes, although the degree of residual endogenous insulin secretion varies considerably between individuals. Serum C-peptide provides an indirect measure of endogenous insulin production and may help characterize metabolic heterogeneity in established diabetes. This study assessed serum C-peptide patterns and their relationship with metabolic characteristics in adults with long-standing type 2 diabetes. A cross-sectional study included 168 adults with a diabetes duration of at least 10 years. Fasting C-peptide, fasting glucose, HbA1c, insulin resistance, lipid profile, BMI, waist circumference, and diabetes treatment were assessed. Participants with higher C-peptide concentrations generally had greater BMI, waist circumference, fasting insulin, and HOMA-IR, while those with lower C-peptide demonstrated longer diabetes duration and greater glycemic instability. HbA1c was highest among participants with low C-peptide concentrations. After adjustment for age, sex, diabetes duration, and BMI, C-peptide remained inversely associated with HbA1c and positively associated with HOMA-IR. These findings demonstrate substantial heterogeneity in residual beta-cell function among individuals with long-standing type 2 diabetes.
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