How to manage hypertension in a patient with impaired renal function on Plendil ER (Felodipine)?

Management of Hypertension in a Patient with Impaired Renal Function on Felodipine

For a 78-year-old hypertensive patient with impaired renal function (eGFR 55 mL/min/1.73m²) currently on Plendil ER (felodipine) 2.5mg daily, continue felodipine and consider optimizing the regimen by adding a renin-angiotensin system blocker to improve blood pressure control and provide renoprotection.

Current Patient Assessment

• 78-year-old male with hypertension
• Current medication: Felodipine ER 2.5mg once daily
• Laboratory values:
  • Sodium: 138 mmol/L (normal)
  • Potassium: 4.5 mmol/L (normal)
  • Creatinine: 87 umol/L (normal)
  • eGFR: 55 mL/min/1.73m² (moderately reduced)
  • Urate: 0.26 mmol/L (normal)

Management Strategy

Step 1: Evaluate Current Therapy

• Felodipine is appropriate for patients with impaired renal function as it doesn't require dose adjustment for renal impairment 1
• Research shows felodipine can be beneficial in patients with reduced renal function, potentially improving GFR in hypertensive patients 2, 3
• Pharmacokinetics of felodipine are not significantly altered in renal impairment 4

Step 2: Optimize Antihypertensive Regimen

Recommended Approach:

1. Continue felodipine as it's well-tolerated and appropriate for patients with reduced renal function

2. Add a renin-angiotensin system (RAS) blocker:

   • An ACE inhibitor or ARB should be added as they provide renoprotection 5
   • For patients with CKD, RAS inhibitors are first-line drugs because they reduce albuminuria in addition to BP control 5

3. Target blood pressure goal: <130/80 mmHg 5

   • The 2024 ESC guidelines recommend targeting systolic BP of 120-129 mmHg for most adults 5
   • For patients with CKD, maintaining BP <130/80 mmHg is recommended to slow progression of renal dysfunction 5

Step 3: Monitoring and Follow-up

• Monitor eGFR, electrolytes (particularly potassium) within 1-2 weeks after initiating RAS blocker 5
• Assess for orthostatic hypotension, especially important in elderly patients 5
• Regular monitoring of proteinuria as a marker of renal disease progression 5

Special Considerations for This Patient

Age-Related Factors

• At 78 years, careful dose titration is warranted
• Start RAS blockers at low doses and titrate gradually
• Monitor for orthostatic hypotension 5

Renal Function

• eGFR of 55 mL/min/1.73m² indicates Stage 3a CKD
• Thiazide-like diuretics remain effective at this level of renal function 5
• If eGFR declines below 30 mL/min/1.73m², consider switching to loop diuretics 5

Potential Treatment Algorithm

1. First step: Add an ARB (preferred over ACE inhibitor due to lower incidence of cough)
2. If BP remains uncontrolled: Add a thiazide-like diuretic (chlorthalidone or indapamide)
3. If further treatment needed: Consider adding a mineralocorticoid receptor antagonist with careful potassium monitoring 5

Pitfalls to Avoid

• Avoid combining two RAS blockers (ACE inhibitor + ARB) as this increases adverse effects without additional benefit 5
• Avoid non-dihydropyridine CCBs (verapamil, diltiazem) in patients with heart failure 5
• Monitor for peripheral edema, a common side effect of dihydropyridine CCBs like felodipine
• Be cautious with aggressive BP lowering in elderly patients; monitor for symptoms of hypoperfusion

Felodipine has been shown to be effective and safe in patients with impaired renal function, with studies showing it may even improve GFR in some hypertensive patients with renal impairment 6, 7. The combination of a dihydropyridine CCB like felodipine with a RAS blocker provides complementary mechanisms of action for BP control while offering renoprotection.