P2643Antiproteinuric efficacy of ACE inhibitors, selective MRAs and ACE inhibitor/selective MRA combination therapy in diabetic hypertensives with microalbuminuria

Abstract

Background There is increasing evidence suggesting use of Mineralocorticoid Receptor Antagonists (MRA) in combination with Angiotensin Converting Enzyme Inhibitors (ACEI) or Angiotensin Receptor Blockers (ARB) to have a protective effect on chronic kidney disease patients. Purpose The aim of our study was to compare the antiproteinuric efficacy of ACEI monotherapy, Selective MRA monotherapy and their combination in mildly hypertensive patients with type 2 diabetes mellitus (DM) and microalbuminuria. Methods Seventy five patients with established diagnosis of type 2 DM, mild hypertension (systolic BP 140–159 mmHg and/or diastolic BP 90–99 mmHg) and microalbuminuria (30–299mg/g) were randomly assigned to one of three groups of therapy; ramipril 10 mg monotherapy (25 patients), eplerenone 50 mg monotherapy (25 patients) and eplerenone/ramipril 50/10 mg combination therapy (25 patients).The duration of the study was 24 weeks. All patients had measurement of blood pressure, urinary albumin/creatinine ratio, renal function tests and serum K level at baseline and at the end of the study after 24 weeks. All patients were followed up monthly till the end of the study for detection of side effects and/or treatment failure. Results Both ramipril and eplerenone monotherapy significantly reduced microalbuminuria after 24 weeks nearly to the same extent (37% and 38% respectively) without significant difference between both groups (P=0.95). There was more significant reduction of microalbuminuria in the eplerenone/ramipril combination group (60%) compared with ramipril and eplerenone monotherapy groups (P=0.0001).All groups showed significant reduction of both systolic and diastolic BP with more significant reduction of systolic BP in combination group compared with monotherapy groups (P<0.0001).There was insignificant elevation of serum potassium level among the three groups with slightly higher non significant incidence of sustained hyperkalemia in combination group (P=0.5). All groups showed insignificant changes in serum creatinine and estimated glomerular filtration rate. Conclusion Addition of eplerenone (selective MRA) to an ACE inhibitor may confer further antiproteinuric benefit with low risk of hyperkalemia compared with MRA or ACEI monotherapy. Acknowledgement/Funding None