Homoarginine as a laboratory cardiovascular risk biomarker

Abstract

Background. Low plasma concentration of L-homoarginine (hArg) is associated with the progression of cardiovascular disease. However, the association between plasma hArg and cardiovascular complications in hypertension is not established. Objective. To assess and compare hArg levels as a biomarker of cardiovascular risk in hypertension. Design and methods. We included 60 hypertensives with moderate (n = 12), high (n = 16) and very high (n = 32) cardiovascular risk. Blood plasma tests including hArg were assessed. The control group included 30 age-matched regular donors. Results. The level of hArg was significantly lower in hypertensives compared to ocontrols (р < 0,001). There were negative correlations between hArg and echocardiography parameters of left ventricular hypertrophy. In the higher cardiovascular risk groups hArg was lower (р = 0,042). ROC-analysis showed AUC 0,860 (95 % confidence interval 0,787–0,933) with the threshold for hArg ≤ 1,69 µM, sensitivity 72,0 % and specificity 93,3 %. Conclusion. The hArg plasma level is associated with the expression and enzyme activity of the protein arginine: glycinamidinetransferase in various tissues. The hArg level ≤ 1,69 µM can be considered a cumulative laboratory biomarker of high cardiovascular risk. Further studies of prognostic and diagnostic role of hArg are needed.