Aims

To study the association between baseline level of C-peptide and all-cause death, cardiovascular death and cardiovascular complications among persons with newly diagnosed type 2 diabetes.

Methods

The Skaraborg Diabetes Register contains data on baseline C-peptide concentrations among 398 persons <65 years with newly diagnosed type 2 diabetes 1996–1998. National registries were used to determine all-cause death, cardiovascular death and incidence of myocardial infarction and ischemic stroke until 31 December 2014. The association between baseline C-peptide and outcomes were evaluated with adjustment for multiple confounders by Cox regression analysis. Missing data were handled by multiple imputation.

Results

In the imputed and fully adjusted model there was a significant association between 1 nmol/l increase in C-peptide concentration and all-cause death (HR 2.20, 95% CI 1.49–3.25, p < 0.001, number of events = 104), underlying cardiovascular death (HR 2.69, 1.49–4.85, p = 0.001, n = 35) and the composite outcome of underlying cardiovascular death, myocardial infarction or ischemic stroke (HR 1.61, 1.06–2.45, p = 0.027, n = 90).

Conclusions

Elevated C-peptide levels at baseline in persons with newly diagnosed type 2 diabetes are associated with increased risk of all-cause and cardiovascular mortality. C-peptide might be used to identify persons at high risk of cardiovascular complications and premature death.