Metabolic factors affecting residual beta cell function assessed by C-peptide secretion in patients with newly diagnosed type 1 diabetes

Horm Metab Res. 2006 Oct;38(10):668-72. doi: 10.1055/s-2006-954586.

Abstract

Background: In recent onset of type 1 diabetes, the residual beta cell function, assessed by baseline and/or stimulated C-peptide secretion, can be a useful parameter to establish the extension of beta cell destruction. How metabolic parameters at diagnosis influence residual C-peptide secretion is not well established.

Patients and methods: We analyzed 553 consecutive patients with recent onset (<4 weeks) of type 1 diabetes (250 females and 303 males, mean age 15+/-8 years). Baseline and stimulated C-peptide by i.v. glucagon were evaluated using a highly sensitive radio-immunoassay. Metabolic parameters including blood glucose, HbA1c, insulin dose, and BMI were also evaluated.

Results: Baseline and stimulated C-peptide were 0.26+/-0.22 and 0.47+/-0.38 nmol/l and correlated positively with age (p<0.001). There was no significant correlation between C-peptide and blood glucose at diagnosis. BMI was positively correlated with both baseline and stimulated C-peptide secretion (p<0.001). By contrast, HbA1c levels inversely correlated with both baseline and stimulated C-peptide secretion (p<0.001).

Conclusion: In type 1 diabetes at diagnosis, baseline and stimulated C-peptide are higher in pubertal and young adult patients compared with pre-pubertal patients suggesting that such parameter can be used as an end point marker for studies aimed at protecting and/or restoring beta cells in patients with substantial beta cell function. High levels of HbA1c and lower BMI are dependent variables of C-peptide values.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Biomarkers / blood*
  • Body Mass Index
  • C-Peptide / blood*
  • C-Peptide / metabolism
  • Child
  • Child, Preschool
  • Diabetes Mellitus, Type 1 / blood*
  • Diabetes Mellitus, Type 1 / diagnosis*
  • Diabetes Mellitus, Type 1 / drug therapy
  • Early Diagnosis
  • Female
  • Glucagon
  • Glycated Hemoglobin A / metabolism
  • Hormones
  • Humans
  • Hypoglycemic Agents / administration & dosage
  • Insulin / administration & dosage
  • Insulin-Secreting Cells / metabolism*
  • Male
  • Multivariate Analysis
  • Prognosis
  • Radioimmunoassay

Substances

  • Biomarkers
  • C-Peptide
  • Glycated Hemoglobin A
  • Hormones
  • Hypoglycemic Agents
  • Insulin
  • Glucagon