Fasting C-peptide, a biomarker for hypoglycaemia risk in insulin-naïve people with type 2 diabetes initiating basal insulin glargine 100 U/mL.

FCP levels identified patients with type 2 diabetes experiencing different responses to basal insulin Gla-100. A low FCP identifies a markedly insulin-deficient, insulin-sensitive subgroup/phenotype with an enhanced risk of hypoglycaemia, which requires a low initial basal insulin dose, cautious titration and earlier addition of prandial glucose-lowering therapy.