Angiotensin Receptor Blockers and Kidney Function

Introduction to ARB Therapy

• The American Diabetes Association guidelines state that ARBs should not be discontinued for increases in serum creatinine less than 30% in the absence of volume depletion 2, 3
• The European Society of Cardiology guidelines consider creatinine increase up to 50% above baseline or up to 266 μmol/L (3 mg/dL), whichever is smaller, as acceptable 4

Mechanism of Action and Expected Changes

• ARBs alter intrarenal hemodynamics by reducing glomerular filtration pressure, leading to predictable increases in both BUN and serum creatinine 1, 2, 3
• The American College of Cardiology notes that a 10-25% increase in serum creatinine may occur in patients with CKD as a result of ARB therapy, and this is considered acceptable 7, 8, 9

Clinical Evidence and Monitoring

• The ACCORD BP trial demonstrated that patients with up to 30% increases in serum creatinine during intensive blood pressure lowering (which included ARB use) had no increase in mortality or progressive kidney disease 1, 5
• Annual monitoring of both albuminuria and eGFR is essential after initiating ARB therapy to maximum tolerated doses 1, 2

Management and Dosage

• For creatinine/BUN increases <30%, continue ARB therapy, ensure adequate hydration, and monitor potassium and creatinine periodically 2, 3, 4
• For creatinine increases 30-50%, exclude volume depletion, stop potassium supplements and potassium-sparing diuretics, and consider reducing diuretic dose if no congestion present 4
• For creatinine increases >50% or >266 μmol/L (3 mg/dL), halve the ARB dose and seek specialist consultation if no improvement 4