[Residual insulin secretion and management of type 1 diabetes: Interest of new C-peptide assays].

Plasma C-peptide represents a direct measure of endogenous insulin secretion. The development of new assays for measuring C-peptide have made it possible to demonstrate that a low insulin secretion persists in 30 to 80% of subjects with type 1 diabetes (T1D), even among those with long-standing disease. Several studies have established that the persistence of B cell function of the islets of Langerhans is associated with a protection against the development of microvascular complications and resulted in a significant reduction in the prevalence of severe hypoglycaemia in people with T1D. Further studies are needed to clarify the underlying pathophysiological mechanisms and the therapeutic strategies that would maintain B-cell function and thus improve the quality of life of patients with T1D.