First-phase insulin release during the intravenous glucose tolerance test as a risk factor for type 1 diabetes

J Pediatr. 2001 Feb;138(2):244-9. doi: 10.1067/mpd.2001.111274.


Objective: To determine the relationship between first-phase (1 minute + 3 minutes) insulin production during the intravenous glucose tolerance test (IV-GTT) and risk factors for developing type 1 diabetes.

Study design: Relatives of persons with type 1 diabetes (n = 59,600) were screened for islet cell antibodies (ICAs). Subjects who had positive screening results underwent IV-GTT (> or =2 times), repeat ICA screening, insulin autoantibody (IAA) screening twice, and an oral glucose tolerance test.

Results: Of the 59,600 subjects in the study, 2199 (3.69%) had positive findings on initial ICA test. IV-GTTs were performed in 1622 subjects, with children <8 years having the lowest first-phase insulin release (FPIR) and subjects 8 to 20 years of age having the highest FPIR. The FPIR was lower for subjects with a confirmed positive ICA test result or a positive IAA test result, subjects with higher titers of ICA or IAA, and subjects who had an abnormal (impaired or diabetic) oral glucose tolerance test result.

Conclusion: FPIR in the IV-GTT correlates strongly with risk factors for development of type 1 diabetes.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Child
  • Child, Preschool
  • Diabetes Mellitus, Type 1 / etiology*
  • Glucose Tolerance Test / adverse effects*
  • Humans
  • Insulin / metabolism*
  • Insulin Secretion
  • Middle Aged
  • Risk Factors


  • Insulin