Relationship between gamma-glutamyl transferase and glucose intolerance in first degree relatives of type 2 diabetics patients

Abstract

• BACKGROUND: Considering that serum gamma-glutamyl transferase (GGT) activity could reflect several different processes relevant to diabetes pathogenesis and the increasing rate of type 2 diabetes worldwide, the aim of this study was to assess the association between serum GGT concentrations and glucose intolerance, in the first-degree relatives (FDR) of type 2 diabetic patients.
• METHODS: In this descriptive study, 30-80 years old, non diabetic FDRs of type 2 diabetic patients were studied. Serum GGT was measured by enzymatic photometry method in all studied population. The relationship between GGT and glucose intolerance status (normal, prediabetic and diabetics) was evaluated.
• RESULTS: During this study 551 non-diabetic FDRs of type 2 diabetic patients were studied. Mean of GGT was
  25.3 ± 12.1 IU/L. According to glucose tolerance test, 153 were normal and 217 and 181 were diabetic and prediabetic respectively. Mean of GGT in normal, prediabetic and diabetic patients was 23.5 ± 15.9 IU/L, 29.1 ± 28.1 IU/L and 30.9 ± 24.8 IU/L respectively (p = 0.000). The proportion of prediabetic and diabetic patients was higher in higher quartile of GGT and there was a significant correlation between GGT and BMI, HbA1c, FPG, cholesterol, LDL-C, and triglyceride (p < 0.05). There was a significant relation between GGT and area under the curve (AUC) of oral glucose tolerance test (p = 0.00).
• CONCLUSIONS: Measurement of GGT in FDRs of type 2 diabetic patients may be useful in assessing the risk of diabetes; those with chronically high levels of GGT should be considered as high risk group for diabetes.
• KEYWORDS: Gamma-Glutamyltransferase, Glucose Intolerance, Diabetes Mellitus, Type 2.