title: Residual β-Cell function 3-6 years after onset of type 1 diabetes reduces risk of severe hypoglycemia in children and adolescents.
abstract: OBJECTIVE
  To determine the prevalence of residual β-cell function (RBF) in children after 3-6 years of type 1 diabetes, and to examine the association between RBF and incidence of severe hypoglycemia, glycemic control, and insulin requirements.
  
  
  METHODS
  A total of 342 children (173 boys) 4.8-18.9 years of age with type 1 diabetes for 3-6 years were included. RBF was assessed by testing meal-stimulated C-peptide concentrations. Information regarding severe hypoglycemia within the past year, current HbA1c, and daily insulin requirements was retrieved from the medical records and through patient interviews.
  
  
  RESULTS
  Ninety-two children (27%) had RBF >0.04 nmol/L. Patients with RBF <0.04 nmol/L were significantly more likely to have severe hypoglycemia than patients with RBF >0.04 nmol/L (odds ratio, 2.59; 95% CI, 1.10-7.08; P < 0.03). HbA1c was significantly higher in patients with RBF <0.04 nmol/L compared with patients with RBF >0.04 nmol/L (mean, 8.49 ± 0.08% [69.3 ± 0.9 mmol/mol] vs. 7.92 ± 0.13% [63.1 ± 1.4 mmol/mol]; P < 0.01), and insulin requirements were significantly lower in patients with RBF >0.2 nmol/L (mean ± SE: 1.07 ± 0.02 vs. 0.93 ± 0.07 units/kg/day; P < 0.04).
  
  
  CONCLUSIONS
  We demonstrated considerable phenotypic diversity in RBF among children after 3-6 years of type 1 diabetes. Children with RBF are at lower risk for severe hypoglycemia, have better diabetes regulation, and have lower insulin requirements compared with children without RBF. There appears to be a lower limit for stimulated RBF of ∼0.04 nmol/L that confers a beneficial effect on hypoglycemia and metabolic control.
authors.affiliation: Corresponding author: Jesper S. Sørensen, jesper.sand@dadlnet.dk.
authors.forename: Jesper S
authors.initials: JS
authors.lastname: Sørensen
authors.forename: Jesper
authors.initials: J
authors.lastname: Johannesen
authors.forename: Flemming
authors.initials: F
authors.lastname: Pociot
authors.forename: Kurt
authors.initials: K
authors.lastname: Kristensen
authors.forename: Jane
authors.initials: J
authors.lastname: Thomsen
authors.forename: N Thomas
authors.initials: NT
authors.lastname: Hertel
authors.forename: Per
authors.initials: P
authors.lastname: Kjaersgaard
authors.forename: Caroline
authors.initials: C
authors.lastname: Brorsson
authors.forename: Niels H
authors.initials: NH
authors.lastname: Birkebaek
mesh_terms: D000293:Adolescent; D001786:Blood Glucose / Q000378:metabolism; D002096:C-Peptide / Q000032:analysis; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000188:drug therapy* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007003:Hypoglycemia / Q000188:drug therapy; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D007328:Insulin / Q000627:therapeutic use; D050417:Insulin-Secreting Cells / Q000502:physiology*; D008297:Male; D062407:Meals; D012042:Registries
chemical_list: D001786:Blood Glucose; D002096:C-Peptide; D007004:Hypoglycemic Agents; D007328:Insulin