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.