THE RENIN-ANGIOTENSIN SYSTEM INHIBITORS IN HAEMODIALYSIS: CARDIOPROTECTIVE? TO WHAT EXTENT?

Abstract

Objective: The renin-angiotensin-aldosterone (RAAS) system is one of the most important systems in the pathogenesis of coronary heart disease. Its blockage constitutes a central pillar of cardiovascular therapeutics. Patients in end-stage renal disease or on dialysis are almost invariably excluded from trials evaluating antihypertensive treatments. Angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs) are more cardioprotective than other antihypertensive agents in patients with chronic renal disease but whether this applies also to patients on dialysis is unknown. This study followed a cohort of haemodialysis patients over a median of three years, we analysed all-cause mortality and cardio-vascular admissions for patients under RAAS inhibitors. Design and method: Twenty-seven HD patients were cross-sectionally analysed in the following groups: G1: patients with hypertension under ACE or ARB treatment (n = 10), G2: patients with hypertension under another class (n = 7), G3: non-hypertensive patients (n = 10). Associations with all-cause and cardiovascular mortality were assessed over a median of 3 years of follow-up. Results: Overall we had three homogeneous groups, there was no significant difference between median ages (46,3 vs52,7 vs49,9), initial nephropathy or dialysis vintage (5,9 years vs 5,1 vs 11,4). In G1: 4 patients experienced cardiovascular events (40%), but none of them died of cardiovascular causes/complications. In G2: 4 patients had cardiovascular events (57%) amongst whom two died of its complications. In G3: two patients had cardiovascular events (20%) amongst whom one died. There was statistically no significant difference between our groups in terms of cardiovascular morbidity or mortality and in all-causes mortality. Nevertheless, patients under SRA inhibitors presented the lowest number of cardiovascular mortalities. Conclusions: In the study, we observed that patients with SRA inhibitors experienced less cardio-vascular related death, although it is not enough to conclude its cardioprotective status. Larger studies need to be carried to unveil its utility among haemodialysis patients.