Rate of beta-cell destruction in type 1 diabetes influences the development of diabetic retinopathy: protective effect of residual beta-cell function for more than 10 years

J Clin Endocrinol Metab. 2008 Dec;93(12):4759-66. doi: 10.1210/jc.2008-1209. Epub 2008 Sep 30.

Abstract

Context: Although residual beta-cell function delays the onset and progression of diabetic retinopathy in patients with type 1 diabetes, the rate of beta-cell destruction is variable.

Objective: The aim of the study was to clarify the influence of the rate of beta-cell destruction on the development and progression of diabetic retinopathy in type 1 diabetes.

Design: We performed a historical cohort study regarding residual beta-cell function and retinopathy.

Setting: The study was conducted in the outpatient clinic of a general hospital.

Patients: A total of 254 patients with type 1 diabetes participated.

Main outcome measures: Serum C-peptide and fundus findings were evaluated longitudinally.

Results: The cumulative incidence of mild nonproliferative diabetic retinopathy was higher in the patients without detectable beta-cell function than in those with residual beta-cell function at 20, 15, and 10 yr after the onset of diabetes (P = 0.013, P = 0.006, and P = 0.048, respectively), but not at 5 yr after the onset (P = 0.84). There were higher mean glycosylated hemoglobin values during the entire follow-up period in the patients without detectable beta-cell function at 20 and 15 yr after the onset of diabetes (P = 0.030 and P = 0.042, respectively). Positivity for HLA-A24 and -DQA1 03, as well as the acute onset of diabetes, was associated with early beta-cell loss and also with early development of diabetic retinopathy. Cox proportional hazards analysis showed that undetectable beta-cell function at 20, 15, or 10 yr after the onset of diabetes was an independent risk factor for the development of diabetic retinopathy.

Conclusions: Undetectable beta-cell function within 10 yr of the onset of type 1 diabetes is associated with the earlier occurrence of diabetic retinopathy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Blood Glucose / metabolism
  • C-Peptide / blood
  • Cohort Studies
  • Diabetes Mellitus, Type 1 / pathology*
  • Diabetic Retinopathy / pathology*
  • Disease Progression
  • Female
  • Fundus Oculi
  • Glycated Hemoglobin A / metabolism
  • HLA Antigens / analysis
  • Humans
  • Insulin-Secreting Cells / pathology*
  • Longitudinal Studies
  • Male
  • Multivariate Analysis
  • Pancreatic Function Tests

Substances

  • Blood Glucose
  • C-Peptide
  • Glycated Hemoglobin A
  • HLA Antigens