Is C-peptide a predictor of severity of coronary artery disease in metabolic syndrome? An observational study

Background: Various cardiovascular disease (CVD) risk factors have been implicated to correlate with the severity of the disease. Present study was conducted to correlate one such risk factor i.e. fasting serum C-peptide with the presence or absence and the severity of CVD in Indian population. Methods: 68 patients with metabolic syndrome who underwent coronary angiogram for suspected CVD were included. Their fasting serum C-peptide levels were measured in addition to routine biochemical and cardiological tests. They were divided into 2 groups – those with a positive coronary angiography findings (Group 1) and those with normal coronary angiograms (Group 2). The former group was further divided into those with an Acute Coronary Syndrome (ACS) (Group 1a) and those with Chronic Stable Angina (CSA) (Group 1b). SYNTAX scoring was done to assess the severity of coronary artery disease in groups 1a and 1b. Levels of C-peptide were compared between the groups. Results: The mean C-peptide of all patients was 1.9 (±0.8) ng/mL. Among the group 2 patients, mean serum C-peptide value was 1.6 (±0.4) ng/mL. And it was 2.7 (±0.8) ng/mL and 1.7 (±0.9) ng/mL among the ACS and the CSA groups respectively. The ACS and CSA group had statistically significant higher values of C-peptide compared to patients with normal coronary angiograms. The two-way ANOVA done to find out the variability of C-peptide among the 3 groups revealed significant differences among the groups with a p-value of