Abstract
BACKGROUND: Epidermal growth factor (EGF) plays a crucial role in cellular growth, differentiation, and pancreatic β-cell maintenance. Despite reports on EGF deficiency in diabetic animal models, its relevance in type 2 diabetes (T2D), particularly in relation to obesity, remains underexplored. The present study aimed to evaluate plasma EGF levels in individuals with and without T2D, assess its associations with glycaemic status and clinical parameters, and evaluate the influence of obesity on these relationships. METHODS: A total of 838 eligible participants were selected from the Kuwait Diabetes Epidemiology Program. Of those, 428 were included in a 1:1 case-control analysis (214 T2D and 214 non-diabetics). EGF was measured in plasma using ELISA. Associations between EGF with glycaemic and clinical variables were evaluated using Pearson's correlation, multiple linear regression, and logistic regression analyses. RESULTS: Plasma EGF levels were significantly lower in individuals with T2D compared to non-diabetics (P < 0.001). Among non-diabetics, obese participants had a significantly lower EGF level than their non-obese counterparts (P = 0.03), while no such difference was observed in T2D. EGF negatively correlated with fasting blood glucose in both non-diabetics (P = 0.004) and T2D individuals (P < 0.001). In T2D, EGF negatively correlated with haemoglobin A1C (HbA1C) (P = 0.001), triglyceride (TG) (P = 0.021), and waist-to-hip ratio (WHR) (P = 0.014). Logistic regression confirmed that lower EGF levels were independently associated with T2D but not with general obesity (OR = 0.996, P = 0.001). CONCLUSION: Reduced EGF levels are associated with poor glycaemic control in T2D. These findings highlight EGF's potential as a biomarker for glycaemic dysregulation and support further investigation into its role in diabetes pathophysiology and complications.