The levels of soluble CD40 ligand and C-reactive protein in normal weight, overweight and obese people.

OBJECTIVE Obesity has been suggested as an independent risk factor for cardiovascular disease. Increasing evidence shows that engagement of soluble CD40 ligand (sCD40L) with its receptor plays a crucial role in the pathogenesis of atherosclerosis. The aim of the present study was to test whether obesity is associated with low-grade systemic inflammation as measured by serum high-sensitive C-reactive protein (hsCRP) and sCD40L concentration. METHODS Serum hsCRP and sCD40L concentrations were measured in 148 nondiabetic people. The participants were divided into three groups depending upon their body mass index (BMI) levels: Group 1 (normal weight), BMI<25 kg/m(2); Group 2 (overweight), BMI 25 kg/m(2) to 29.9 kg/m(2); and Group 3 (obese), BMI>or=30 kg/m(2). RESULTS Obese people had more elevated hsCRP levels than both their normal weight and overweight counterparts (P=0.000 and P=0.000, respectively). Similarly, serum concentrations of sCD40L were significantly higher, statistically, in obese subjects compared with normal weight subjects (P=0.003). In addition, obese subjects had higher values of sCD40L than overweight subjects, but the difference did not reach statistical significance (P=0.063). The levels of high-density lipoprotein cholesterol were significantly lower in obese subjects compared to normal weight subjects (P=0.048). The analysis of platelet count disclosed a statistically significant difference between obese subjects and normal weight subjects (P=0.028). The levels of BMI were positively correlated with the serum levels of hsCRP and sCD40L in all subjects (r=0.514, P=0.000 and r=0.283, P=0.000, respectively). Levels of hsCRP were positively correlated with waist circumference, fasting glucose, total cholesterol, triglyceride, low-density lipoprotein cholesterol, leukocytes, platelets, systolic and diastolic blood pressure. Similarly, soluble CD40L levels were positively correlated with waist circumference, fasting glucose and leukocytes. CONCLUSION Obese patients showed a significant increase of hsCRP and sCD40L levels compared with normal weight subjects, which might contribute to the known proinflammatory milieu found in these patients.