Increased levels of sCD40L (soluble
CD40 ligand) have been associated with enhanced in vivo platelet activation, and may represent a molecular link between
inflammation and a prothrombotic state. The aim of the present study was to analyse the relationship between platelet activation, endothelial dysfunction, low-grade
inflammation and sCD40L in patients with
hypertension with or without MA (microalbuminuria). A cross-sectional comparison of sCD40L levels was performed in 25 patients with MH (
essential hypertension with MA) pair-matched for gender and age with 25 patients with EH (
essential hypertension) and 25 HS (healthy subjects with normotension). Circulating levels of CRP (
C-reactive protein), a marker of
inflammation, sP-
selectin (soluble
P-selectin), a marker of in vivo platelet activation, and ADMA (
asymmetric dimethylarginine) and vWF (
von Willebrand factor), markers of endothelial dysfunction, were analysed in each subject. sCD40L levels were increased in patients with MH compared with either patients with EH (P<0.001) or HS (P<0.0001). A highly significant correlation between plasma sCD40L and sP-
selectin (P<0.0001), vWF (P<0.001) or CRP levels (P<0.05) was observed in patients with MH. Multivariate regression analysis showed that sP-
selectin was the strongest independent predictor of sCD40L levels (P<0.0001) in patients with MH. Patients with
hypertension with both vWF and CRP levels above the median had the highest sCD40L levels (P<0.0001). Factorial ANOVA of all of the patients with
hypertension confirmed that only patients with MH with low-grade
inflammation had elevated levels of sCD40L. In conclusion, sCD40L levels appear to discriminate a subset of patients characterized by MA and low-grade
inflammation, suggesting that inhibition of the CD40/
CD40L system may represent a potential therapeutic target in subjects with
hypertension at a high risk of cardiovascular events.