Serum Leptin Levels in Patients with Type 2 Diabetes Mellitus, First Degree Relatives of Diabetic Patients, Prediabetes, Correlation with Carotid Intima Media Thickness

Background: Type 2 diabetes mellitus (T2DM) is characterized by hyperglycemia due to insulin resistance and inadequate secretion, leading to complications. Obesity exacerbates these risks, with leptin implicated in body weight regulation and cardiovascular disease (CVD). Carotid intima-media thickness (CIMT) serves as a noninvasive marker of preclinical atherosclerosis. Aim: To assess serum level of leptin as adibocytokine in patient with type 2 diabetes mellitus, first degree relatives of diabetic patients, prediabetes and control subject and detect its relation to carotid IMT as a measure of preclinical atherosclerosis. Patients and methods: The study included 100 subjects from Internal Medicine Insurance clinics and diabetes & endocrinology unit outpatient clinic in Beni-Suef University hospital from January 2017 until March 2018. They were divided into four groups: Type 2 DM group: twenty-five patients with type 2 diabetes. Prediabetes group: twenty-five. Relatives of diabetic group: twenty-five subjects first degree relative of type 2 diabetic patients. Normal controls group: twenty-five of normal volunteers Results: Leptin levels were significantly higher in T2DM (34±10 ng/ml) and prediabetes (29.6±14.9 ng/ml) vs. relatives (14±6 ng/ml; p<0.05), with females showing elevated levels. CIMT was increased in T2DM (0.81±0.17 mm) and prediabetes (0.71±0.12 mm) vs. relatives (0.45±0.05 mm) and controls (0.62±0.13 mm; p<0.05). Leptin correlated positively with CIMT (r=0.258, p=0.010) and other risk factors. At 15 ng/ml cutoff, leptin predicted increased CIMT (sensitivity 81.5%, specificity 66%; p=0.028). Conclusion: Elevated leptin is associated with increased CIMT in T2DM and prediabetes, indicating accelerated atherosclerosis. CIMT monitoring aids risk assessment; relatives show lower risk.