What are the kidney-sparing medications for treating hypertension?

Kidney-Sparing Medications for Hypertension

For patients with hypertension and kidney disease, ACE inhibitors or ARBs should be considered first-line therapy, especially in those with albuminuria, as they provide superior kidney protection beyond blood pressure reduction alone. 1

First-Line Kidney-Protective Antihypertensive Medications

Renin-Angiotensin System (RAS) Inhibitors

• ACE inhibitors (e.g., lisinopril, enalapril)

  • Reduce intraglomerular pressure by dilating efferent arterioles
  • Decrease proteinuria
  • Slow progression of kidney disease
  • Most beneficial in patients with albuminuria (UACR ≥30 mg/g) 1
  • Mechanism: Block conversion of angiotensin I to angiotensin II 2

• ARBs (e.g., losartan, candesartan)

  • Similar kidney protection as ACE inhibitors
  • May be better tolerated (less cough)
  • Particularly beneficial in diabetic kidney disease 1
  • Strongly recommended for patients with severely increased albuminuria (UACR ≥300 mg/g) 1

Important Considerations for RAS Inhibitors

• Should be administered at the highest tolerated dose to maximize kidney protection 1
• Monitor serum creatinine and potassium within 2-4 weeks of initiation 1
• Expect a small initial decrease in eGFR (up to 30%), which is actually associated with better long-term kidney outcomes 3
• Avoid combination of ACE inhibitor + ARB (increases risk of hyperkalemia and acute kidney injury) 1

Second-Line Kidney-Sparing Options

Calcium Channel Blockers (CCBs)

• Dihydropyridine CCBs (e.g., amlodipine)
  • Effective for BP reduction with neutral kidney effects 1
  • Can be added to RAS inhibitors when additional BP control is needed 1
  • Newer-generation dihydropyridines (e.g., manidipine) may have additional kidney benefits 4

Diuretics

• Thiazide-like diuretics (e.g., chlorthalidone)

  • Preferred over hydrochlorothiazide, especially in advanced CKD 1
  • Effective even in patients with eGFR <30 mL/min/1.73m² 1
  • Chlorthalidone has shown efficacy in lowering BP in advanced CKD 1

• Loop diuretics (e.g., furosemide)

  • Necessary when eGFR <30 mL/min/1.73m² 1
  • Can be combined with thiazides for enhanced diuresis in resistant cases 1

Mineralocorticoid Receptor Antagonists (MRAs)

• Non-steroidal MRAs (e.g., finerenone)

  • Beneficial for patients with diabetic kidney disease and albuminuria 1
  • Provides both kidney and cardiovascular protection 1

• Steroidal MRAs (e.g., spironolactone)

  • Effective for resistant hypertension but may cause hyperkalemia 1
  • Use with caution in advanced CKD 1

Medications to Avoid or Use with Caution

• Beta-blockers

  • Less effective for cardiovascular prevention than diuretics or CCBs 1
  • May be used in specific conditions (ischemic heart disease, heart failure) 1

• Alpha-blockers

  • Should be avoided as first-line therapy 5
  • May be added if other agents are inadequate

• Direct renin inhibitors

  • Avoid combining with ACE inhibitors or ARBs 1

Treatment Algorithm for Hypertension in CKD

1. Initial therapy:

   • For patients with albuminuria (UACR ≥30 mg/g): Start with ACE inhibitor or ARB 1
   • For patients without albuminuria: Any first-line agent (ACE inhibitor, ARB, CCB, or thiazide diuretic) 1

2. If BP target not achieved:

   • Add a complementary agent (CCB or thiazide diuretic if started with RAS inhibitor) 1
   • Use chlorthalidone preferentially over hydrochlorothiazide 1
   • Switch to loop diuretic if eGFR <30 mL/min/1.73m² 1

3. For resistant hypertension:

   • Consider adding MRA (monitor potassium closely) 1
   • Combination of different diuretic classes may be effective 1

4. BP targets:

   • <130/80 mmHg for most CKD patients 1
   • <140/80 mmHg for elderly CKD patients 1

Monitoring Recommendations

• Check serum creatinine and potassium 2-4 weeks after starting or increasing RAS inhibitor dose 1
• Continue RAS inhibitor unless serum creatinine rises by >30% 1
• Consider reducing dose or discontinuing RAS inhibitor if symptomatic hypotension, uncontrolled hyperkalemia, or uremic symptoms develop 1
• Regular monitoring of albuminuria to assess treatment efficacy 1

By following this approach to antihypertensive therapy in patients with kidney disease, you can effectively control blood pressure while maximizing kidney protection and reducing cardiovascular risk.