STUDY OF CORRELATION BETWEEN INSULLIN-LIKE GROWTH FATOR-I AND GLYCOSYLATED HEMOGLOBIN IN TYPE 1 DIABETES

Introduction : Diabetes is a common endocrine disease and complications such as retinopathy, nephropathy and neuropathy are major stimuli for enhancing efforts on controlling it using biomarkers. At present, glycosylated hemoglobin (HbA 1c ) is used for monitoring the long term control of glucose levels in diabetic patients. But due to the lack of availability of a standard range, recent findings suggest that insulin-like growth factor-I (IGF-I) may be used as a standard biomarker for monitoring blood glucose levels in diabetic patients. The aim of this study was to examine the correlation between IGF-I and HbA 1c in Type 1 diabetes. Methods : We designed a cross-sectional case-control study. The study composed of 26 newly diagnosed patients with Type 1 diabetes (15 male and 11 female; mean age, 23.7±9.1 years) and 26 healthy controls (9 male and 17 female; mean age, 24.1±4.4 years). We measured the concentrations of fasting plasma glucose (FPG), HbA 1C , IGF-I and IGF-binding protein-3 (IGFBP-3) in both groups. FPG was measured by enzymatic glucose oxidase method and the colorimetric method was used to measure HbA 1C . Determination of total serum levels of IGF-I and IGFBP-3 were carried out using immunoassay methods. P-value<0.05 was considered as statistically significant. Results: The mean value of IGF-I concentration in type 1 diabetics was significantly lower than controls (p< 0.05). A reverse correlation was observed between IGF-I and HbA 1c . Conclusion: It is speculated that based on this findings, when diabetes is poorly controlled, levels of FPG and HbA 1c increase while level of IGF-I decreases. Our study also showed a significant correlation between IGF-I and HbA 1c . Therefore, IGF-I could be indirectly used as a biomarker for controlling glucose levels in diabetes.