C-peptide persistence in type 1 diabetes: ‘not drowning, but waving’?

Excerpt

One hundred years ago, diabetes was considered to be one disease, although with marked clinical heterogeneity. Adults who developed diabetes could often manage for years with diet alone, but children usually died within 6 months of diagnosis [1]. Once discovered, insulin was used successfully to treat these children. Thereafter, these children were classified as having insulin-dependent diabetes, which was later re-termed as type 1 diabetes with a dependence on insulin to survive. Patients with all types of diabetes were classified as having non-insulin-dependent or type 2 diabetes, although many eventually required insulin treatment themselves, despite their less aggressive disease course. The development of radioimmunoassays for insulin, proinsulin and its cleaved section C-peptide, only tended to confirm that children with diabetes had little or no insulin, while adults often had substantial amounts. This binary approach to diabetes stratification i.e., that patients do or do not secrete insulin has recently been challenged, notably by exploiting immunogenetics and more sensitive protein assays to define the diabetes spectrum and its heterogeneity [1‐3]. …