What are the best antihypertensive drugs to avoid kidney injury in patients with Impaired renal function?

Best Antihypertensive Drugs to Avoid Kidney Injury in Patients with Impaired Renal Function

Renin-angiotensin system inhibitors (RASi), specifically ACE inhibitors or ARBs, are the preferred first-line antihypertensive drugs for patients with impaired renal function, particularly those with albuminuria, as they provide renoprotection and slow kidney disease progression.

First-Line Therapy Based on Albuminuria Status

For Patients with Albuminuria:

• Severely increased albuminuria (≥300 mg/g):

  • ACE inhibitors or ARBs strongly recommended (Grade 1B) 1
  • These agents reduce intraglomerular pressure and albuminuria, slowing kidney disease progression
  • Should be titrated to the highest tolerated dose 1

• Moderately increased albuminuria (30-299 mg/g):

  • ACE inhibitors or ARBs suggested (Grade 2C) 1
  • Beneficial for both cardiovascular protection and renoprotection

For Patients without Albuminuria:

• ACE inhibitors or ARBs may still be reasonable options 1
• Consider individual cardiovascular risk profile

Monitoring and Precautions with RASi

1. Initial monitoring:

   • Check serum creatinine and potassium within 2-4 weeks of initiation or dose increase 1
   • Continue therapy unless serum creatinine rises by >30% within 4 weeks 1

2. Common concerns to address:

   • Hyperkalemia: Can often be managed with dietary measures rather than stopping RASi 1
   • Acute decline in GFR: An initial rise in creatinine up to 30% is expected and not a reason to discontinue therapy 1

3. When to reduce dose or discontinue:

   • Symptomatic hypotension
   • Uncontrolled hyperkalemia despite treatment
   • Serum creatinine rise >30% within 4 weeks of initiation 1

Alternative and Add-on Agents

If BP targets are not achieved with RASi alone or RASi are contraindicated:

1. Dihydropyridine calcium channel blockers (CCBs):

   • Effective add-on therapy, particularly in kidney transplant recipients 1
   • Examples: amlodipine, felodipine 2
   • Caution: Dihydropyridine CCBs alone may not reduce proteinuria despite BP reduction 3

2. Thiazide-like diuretics:

   • Effective even in moderate CKD (eGFR >30 ml/min/1.73m²) 1
   • Chlorthalidone preferred over hydrochlorothiazide 1
   • For advanced CKD (eGFR <30 ml/min/1.73m²), loop diuretics may be more effective 2

3. Mineralocorticoid receptor antagonists (MRAs):

   • Effective for resistant hypertension 1
   • Caution: May cause hyperkalemia or reversible decline in kidney function, particularly with low eGFR 1

Important Combinations to Avoid

1. Never combine ACE inhibitors with ARBs or direct renin inhibitors (Grade 1B) 1

   • Increases risk of hyperkalemia and acute kidney injury
   • No additional benefit for cardiovascular or renal outcomes 1

2. Avoid NSAIDs in patients with kidney disease 1

   • Can cause further kidney function impairment
   • Particularly problematic when combined with RASi

Blood Pressure Targets

• Current recommendation: <130/80 mmHg for patients with CKD 1
• For patients with both CKD and diabetes: <130/80 mmHg 1
• Systolic target of 120-129 mmHg for moderate-to-severe CKD with eGFR >30 ml/min/1.73m² 2

Clinical Pearls

1. Start low, go slow: Begin with lower doses in patients with severe renal impairment (eGFR <30 ml/min/1.73m²) 4

2. Combination therapy: Most patients will require multiple agents to reach target BP 1

3. Monitor for AKI: Pay special attention during intercurrent illness, volume depletion, or when adding other medications that affect kidney function 1

4. Non-dihydropyridine CCBs: May provide additional antiproteinuric effects when combined with RASi in patients with significant proteinuria 3, 5