The renoprotective effect of renin-angiotensin system (RAAS) blockade by ACE inhibitors (ACEI) or AT1 receptor antagonists (ARA) in chronic proteinuric nephropathies is well known. Most studies have related this beneficial effect with the antihypertensive and antiproteinuric properties of these drugs, but this aspect has not been extensively analyzed in patients with normal/low values of blood pressure. We studied nineteen patients with different chronic proteinuric nephropathies that started ACEI or ARA because of proteinuria and despite systolic blood pressure (SBP) < or = 115 mmHg. Short and long-term tolerance to treatment as well as evolution of renal function parameters were recorded.
Results: At baseline, SBP was 110.2 +/- 2.6 mmHg (105-115) an diastolic blood pressure (DBP) 68.6 +/- 4.3 (60-75). Initial low doses of ACEI or ARA were well tolerated. After 6 months of treatment, proteinuria decreased by 46% of baseline, from 2.1 +/- 1.8 g/day to 1.1 +/- 0.8 g/day, without significant changes in BP or renal function. After a 48 +/- 27 months follow up, proteinuria decreased to 0.7 +/- 0.6 g/day (68% of basal values). Renal function and BP did not show significant changes during follow up.
Conclusions: RAAS blockade by ACEI/ARA induces a significant antiproteinuric and renoprotective effect in proteinuric patients with normal/low levels of BP Initial doses of ACEI/ARA were well tolerated.