Beta-score: an assessment of beta-cell function after islet transplantation

Diabetes Care. 2005 Feb;28(2):343-7. doi: 10.2337/diacare.28.2.343.

Abstract

Objective: Success after islet transplantation can be defined in terms of insulin independence, C-peptide secretion, or glycemic control. These measures are interdependent and all need to be considered in evaluating beta-cell function after islet transplantation. For the current study, a composite beta-score was developed that provides an integrated measure of beta-cell function success after islet transplantation.

Research design and methods: The proposed scoring system gave 2 points each for normal fasting glucose, HbA(1c), stimulated C-peptide, and absence of insulin or oral hypoglycemic agent use. No points were awarded if the fasting glucose was in the diabetic range, the HbA(1c) was >6.9%, C-peptide secretion was absent on stimulation, or daily insulin use was in excess of 0.24 units/kg. One point was given for intermediate values. The score ranged from 0 to 8 and was correlated with the glucose value 90 min after a standard mixed meal challenge (n = 218) in 57 subjects before and after islet transplantation. The score was also used to follow subjects for up to 5 years after islet transplantation.

Results: The beta-score correlated well with the plasma glucose level 90 min after a mixed meal challenge (r = -0.849, P < 0.001). On follow-up, the beta-score rose after the first transplant and was maintained up to 5 years, demonstrating continuing function of the transplanted beta-cells.

Conclusions: The beta-score provides a simple clinical scoring system that encompasses glycemic control, diabetes therapy, and endogenous insulin secretion that correlates well with physiological measures of beta-cell function. On this basis, it is suitable as an overall measure of beta-cell transplant function. The beta-score gives an integrated measure of beta-cell function as a continuum that may be more useful than simply assessing the presence or absence of insulin independence.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blood Glucose
  • C-Peptide / blood
  • Diabetes Mellitus, Type 1 / diagnosis*
  • Diabetes Mellitus, Type 1 / drug therapy
  • Diabetes Mellitus, Type 1 / surgery*
  • Glycated Hemoglobin A / metabolism
  • Graft Survival / physiology*
  • Humans
  • Hypoglycemic Agents / therapeutic use
  • Islets of Langerhans / physiology*
  • Islets of Langerhans Transplantation*
  • Postprandial Period
  • Severity of Illness Index*

Substances

  • Blood Glucose
  • C-Peptide
  • Glycated Hemoglobin A
  • Hypoglycemic Agents