Evaluation of Serum Gamma Glutamyl Transferase Levels in Diabetic Patients With and Without Retinopathy

Abstract

Background: Gamma glutamyl transferase (GGT) is a liver enzyme that is involved in oxidative stress. The association between GGT levels and diabetes complications such as microalbuminuria, retinopathy, and peripheral polyneuropathy is a challenging subject. Objectives: In this study we compared GGT levels in orally treated DM type 2 patients with and without retinopathy. Methods: In this cross-sectional study that was done between the years of 2011 and 2012, 208 patients with Type 2 DM, aged 30 - 86 years old, who had received oral agents, and referred to the Endocrine clinic of Emam Khomeini hospital of Urmia city were enrolled. In all patients blood pressure, body mass index, and biochemical tests including fasting blood sugar (FBS) and GGT levels were measured and an ophthalmologic exam was done. Results: From 208 patients with Type 2 DM, 26 subjects (12.5%) had diabetic retinopathy; however, 182 subjects (87.5%) did not have it. Both systolic and diastolic blood pressures were significantly higher in DM 2 patients with retinopathy than those without retinopathy (P values = 0.003 and 0.022, respectively). The mean of GGT level significantly increased in diabetic patients with retinopathy compared those DM 2 patients who did not have retinopathy (P value < 0.001). Prevalence of GGT levels greater than 45 U/l was 61.5% (n = 16) and 10.4% (n = 19) in diabetic patients with and without retinopathy, respectively (P value < 0.001). Conclusions: We suggest that diabetic retinopathy might have an association with higher GGT levels.