Serum C-peptide levels predict cardiovascular death risk
medwireNews: Levels of C-peptide predict the risk for death from cardiovascular disease in nondiabetic adults, show data from the US National Health and Nutrition Examination Survey (NHANES).
Individuals with serum levels of the pancreatic-produced peptide in the highest quartile (>1.018 nmol/L) had a 3.2-fold increased risk for death from cardiovascular causes when compared with individuals in the lowest quartile (<0.440 nmol/L).
Furthermore, high C-peptide levels were associated with a 2.73-fold increase in coronary artery disease mortality and a 1.8-fold increased risk for death from any cause.
"This risk was progressive," say Korean researchers Jin-young Min (Seoul National University) and Kyoung-bok Min (Ajou University School of Medicine, Suwon) in the Canadian Medical Association Journal. "After adjustment, each 1-unit increase in baseline C-peptide was associated with a 41-70% increase in the relative risk of death."
C-peptide is secreted along with insulin by pancreatic beta cells. Until recently it was considered an inert byproduct of insulin synthesis, but recent data suggest that it is bioactively linked to cardiovascular death.
The researchers used data from NHANES 1988-1994, and linked mortality data from the US National Death Index up until 2006. A total of 5902 adults aged 40 years or older who did not have diabetes were identified for the analysis.
The mean serum C-peptide level was 0.78 nmol/L for the entire cohort, but was found to be significantly more likely to be elevated in certain individuals, such as men, older people, former smokers, and nondrinkers. Higher levels were also found in people with a low level of education and who had a Hispanic background.
Average C-peptide levels were also significantly higher in people with a history of hypertension, hypercholesterolemia, or heart attack, as well as in those with increased bodyweight, and high levels of C-reactive protein, total cholesterol, triglycerides, serum insulin, glycated hemoglobin, and fasting serum glucose.
"We found that C-peptide level better predicted all-cause, cardiovascular-related and coronary artery disease-related mortality than did glycated hemoglobin or fasting blood glucose level," the researchers comment.
Noting that the study's findings are consistent with previous research, the team adds that these data "suggest a role for C-peptide in predicting increased risk of cardiovascular events and death regardless of the presence of diabetes."
medwireNews (www.medwirenews.com) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2013
By Sara Freeman, medwireNews Reporter