Relationship between serum leptin, lipid metabolism, HbA1c, and renal function in individuals with type 2 diabetes mellitus and obesity and in individuals with type 2 diabetes mellitus without obesity

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder characterized by hyperglycemia, impaired lipid metabolism, and insulin resistance. In addition to the traditional risk factors, recent studies have suggested that adipose tissue-derived hormones such as leptin play a crucial role in the pathogenesis of T2DM and its related complications. However, the exact mechanism underlying the relationship between serum leptin levels and these comorbidities remains unclear. The study included 222 individuals, with 74 having T2DM and obesity, 74 having T2DM without obesity, and 74 in the control group. Serum levels of leptin, total cholesterol, triglycerides, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and HbA1c were measured, and the glomerular filtration rate (GFR) was used as a measure of renal function. Serum leptin levels were significantly higher in individuals with T2DM and obesity compared to those without obesity (P < .05). Additionally, total cholesterol, triglycerides, and LDL were significantly higher in individuals with T2DM and obesity compared to those without obesity (P < .05). Serum leptin levels were positively correlated with total cholesterol, triglycerides, and LDL (P < .05) and negatively correlated with HDL (P < .01). The GFR was not significant when both groups were compared. Obesity has a negative impact on lipid profile and glycemic control in type 2 diabetes patients, which highlights the significance of considering the effect of obesity on the relationship between leptin and lipid profile in diabetic patients. These findings suggest that targeting obesity and leptin levels may be an effective strategy for improving lipid profiles and glycemic control in type 2 diabetes.