Retinal microvascular changes and target organ damage in untreated essential hypertensives

Abstract

The clinical and prognostic significance of initial retinal alterations in hypertensive patients remains controversial. Therefore, we assessed the relationship of microvascular abnormalities with prognostically validated markers of target organ damage (TOD), such as left ventricular mass (LVM), carotid intima-media thickness (IMT) and microalbuminuria, in early stages of untreated essential hypertension. A total of 437 consecutive, never-treated patients with grade 1 or 2 essential hypertension, referred to our outpatient clinic, underwent the following procedures: (1) clinical and routine laboratory examinations, (2) 24-h ambulatory blood pressure monitoring, (3) 24-h urine collection for microalbuminuria, (4) echocardiography, (5) carotid ultrasonography, (6) non-mydriatic retinography. Patients were divided into group I, with either a normal retinal pattern (n=65, 14.9%) or arteriolar narrowing (n=185, 42.4%) and group II with arteriovenous crossings (n=187, 42.7%). The two groups were similar for gender, body mass index, smoking habit, heart rate, clinic and ambulatory blood pressure (BP) values, while mean age was slightly but significantly higher in group II than in group I (47.6 +/- 10.7 versus 44.5 +/- 12.5 years, P=0.008). No differences occurred between the two groups in LVM index (101.8 +/- 18.5 versus 99.9 +/- 20.4 g/m), carotid IMT (0.67 +/- 0.12 versus 0.66 +/- 0.20 mm), urinary albumin excretion rate (14.4 +/- 27.7 versus 13.3 +/- 27.7 mg/24 h) as well as in the prevalence of LV hypertrophy (14.3 versus 14.0%), IM thickening and/or plaques (26.5 versus 27.2%) (both defined according to 2003 ESH-ESC guidelines) and microalbuminuria (10.1 versus 8.7%). Furthermore, the three different retinal artery patterns were similarly distributed among tertiles of LV mass index, IMT and urinary albumin excretion rate. These results show that: (1) a very large fraction (more than 80%) of untreated, recently diagnosed hypertensive patients have initial retinal microvascular abnormalities detectable by non-mydriatic retinography, (2) the presence of arteriovenous crossings is not associated with more prominent cardiac and extracardiac TOD, (3) fundoscopic examination has a limited clinical value to detect widespread organ involvement in early phases of grade 1 and 2 hypertension.