Mohammad Faruque
Objectives: It is possible that insulin resistance and dysfunction in B-cell secretory function are associated with serum free insulin like growth factors-1 (IGF-1) and insulin like growth factor binding protein-1 (IGFBP-1). The purpose of this study is to determine whether type 2 diabetics in a Bangladeshi population have two distinct associations with IGF-1 and IGFBP-1.
Methods: Sixty-eight people with type 2 diabetes (DM) and 61 healthy controls without a family history of diabetes or prediabetes are studied alongside age, sex, and BMI-matched controls. The standard ELISA method is used to measure insulin, free IGF-1, and IGFBP-1. HOMA-CIGMA software uses fasting glucose and fasting insulin to calculate insulin secretory capacity (HOMA B) and sensitivity (HOMA S).
Results: The study groups did not significantly differ in their free IGF-1 and IGFBP-1 levels while fasting. However, when compared to controls in the low BMI group (BMI 23), the level of free IGF-1 in type 2 DM subjects is significantly higher (p = 0.03). There is a clear positive association between HOMA B and free IGF-1 in stepwise multiple regression analysis. In a similar manner, IGFBP-1 is positively correlated with HOMA B and HOMA S in various models. In different stepwise multiple regression analysis models, both free IGF-1 and IGFBP-1 have an inverse relationship with fasting insulin in the same study.
Conclusion: Fasting insulin levels are negatively correlated with both IGF- 1 and IGFBP-1. IGF-1 is also positively associated with B-cell secretory dysfunction, and insulin sensitivity and IGFBP-1 are also positively associated with B-cell secretory dysfunction in type 2 diabetic patients.