Is retinal arteriolar–venular ratio associated with cardiac and extracardiac organ damage in essential hypertension?

Abstract

Whether retinal microvascular disease is associated with markers of cardiac and extracardiac organ damage in human hypertension is still unclear. We examined the relationship between retinal arteriolar-venular ratio (AVR) and left ventricular hypertrophy, carotid atherosclerosis and microalbuminuria in essential hypertension. A total of 386 untreated and treated uncomplicated essential hypertensive individuals (mean age 56 +/- 13 years) consecutively attending our hospital outpatient hypertension clinic were considered for the analysis. All individuals underwent extensive clinical and laboratory investigations, including retinal AVR evaluation by a fully automated computer-assisted method, echocardiography and carotid ultrasonography. Mean retinal AVR was 0.790 +/- 0.079 (range 0.530-0.990). In univariate analyses, AVR showed a significant inverse association with left ventricular mass index (r = -0.15, P = 0.002) and carotid intima-media thickness (IMT) (r = -0.12, P = 0.02); no relationship with microalbuminuria was found. Overall, left ventricular mass index and carotid IMT as well as microalbuminuria, either as continuous or categorical variables, did not show significant differences across AVR quartiles. Moreover, a multivariate analysis failed to demonstrate independent correlations of carotid IMT and left ventricular mass index (P = 0.06 for both) with AVR. Finally, when patients were categorized according to the presence or absence of organ damage, with or without left ventricular hypertrophy (0.783 +/- 0.077 vs. 0.795 +/- 0.081), carotid plaques (0.789 +/- 0.079 vs. 0.791 +/- 0.079), carotid IMT (0.791 +/- 0.077 vs. 0.788 +/- 0.082) or microalbuminuria (0.791 +/- 0.080 vs. 0.777 +/- 0.073), no significant intergroup differences in AVR values were found. Our findings provide further evidence that retinal AVR is of limited value in identifying hypertensive patients at high cardiovascular risk related to cardiac and extracardiac organ damage.