Diagnostic biomarkers of essential arterial hypertension: the value of prostacyclin, nitric oxide, oxidized-LDL, and peroxide measurements.

Endothelial function is impaired in hypertensive patients. Decreased nitric oxide and prostacyclin production as well as increased oxidative stress are involved in this abnormality. The aim of the present study was to evaluate whether biomarkers of endothelial dysfunction and oxidative stress have diagnostic value in patients with essential hypertension. We measured nitric oxide, prostacyclin, and oxidized-LDL levels and assessed oxidative status in 62 patients with diagnosed essential arterial hypertension and 45 healthy controls. In the hypertensive group, among measured parameters, the median prostacyclin level was significantly lower, when compared to healthy controls (125.57 pg/mL, 25%; 75% quartile range: 84.99; 275.93 and 462.9 pg/mL, 25%; 75% quartile range: 107.69; 849.3, respectively, P = 0.009). The largest area under the ROC curve was found for prostacyclin; 0.647 (95% C.I. 0.549 to 0.737). In the analysis of logistic regression, the prostacyclin and oxidized-LDL cut-off values were associated with a 4.9 higher significant risk of hypertension (O.R. 4.91 and 4.99, respectively; P = 0.0008 and P = 0.00065, respectively). Oxidized-LDL, a biomarker of endothelial damage, was the only one that had a significant negative correlation with protective prostacyclin in hypertensive patients (r = -0.29, P = 0.02). Of all the biomarkers prostacyclin and oxidized-LDL had the best diagnostic value for patients with hypertension.