In a patient with chronic kidney disease and an estimated glomerular filtration rate of 45 mL/min/1.73 m² who is taking atenolol 50 mg daily, how should the atenolol be managed?

Atenolol Management in CKD Stage 3a

With an eGFR of 45 mL/min/1.73 m², the current atenolol 50 mg daily dose is appropriate and should be continued without adjustment, but you must transition this patient to guideline-directed medical therapy with an ACE inhibitor or ARB as the primary antihypertensive agent.

Immediate Atenolol Dosing Assessment

The current dose of atenolol 50 mg daily is safe and does not require adjustment at this level of kidney function. According to the FDA label, atenolol accumulation does not occur until creatinine clearance falls below 35 mL/min/1.73 m² 1. The recommended maximum dosage for patients with creatinine clearance 15-35 mL/min/1.73 m² is 50 mg daily, and for those <15 mL/min/1.73 m² is 25 mg daily 1. Since this patient has an eGFR of 45 mL/min/1.73 m², they are above the threshold requiring dose reduction.

Key Pharmacokinetic Considerations:

• Atenolol is renally excreted, with elimination half-life increasing from 5.9 hours in normal renal function to 16-27 hours when creatinine clearance is 15-35 mL/min/1.73 m² 2
• At eGFR 45 mL/min/1.73 m², no significant drug accumulation is expected
• Monitor for bradycardia or hypotension as indicators of excessive beta-blockade

Critical Medication Optimization Required

The more important issue is that atenolol should NOT be the primary antihypertensive agent in CKD. The 2024 KDIGO guidelines provide clear direction on optimal antihypertensive therapy for kidney protection 3:

Guideline-Directed Therapy Algorithm:

1. First-line: ACE inhibitor or ARB

   • Start RASi therapy based on albuminuria status 3:
     • Severely increased albuminuria (A3): Strong recommendation to start RASi (1B evidence)
     • Moderately increased albuminuria (A2): Suggested to start RASi (2C evidence)
     • Normal/mildly increased albuminuria (A1): Consider RASi for hypertension control

2. Second-line: Add SGLT2 inhibitor

   • For eGFR 20-45 mL/min/1.73 m² with ACR <200 mg/g: Suggested (2B evidence) 3
   • For eGFR ≥20 mL/min/1.73 m² with ACR ≥200 mg/g: Strong recommendation (1A evidence) 3

3. Beta-blocker role: Reserve for specific cardiac indications (heart failure with reduced ejection fraction, post-MI, angina)

Practical Management Steps

Immediate actions:

• Check urine albumin-to-creatinine ratio to determine albuminuria category
• Assess blood pressure control and cardiac indications for beta-blockade
• Continue atenolol 50 mg daily while initiating RASi therapy

Transition strategy:

• Start ACE inhibitor or ARB at standard dose (use maximum tolerated dose per guidelines) 3
• Check BP, creatinine, and potassium within 2-4 weeks of RASi initiation 3
• Continue ACE inhibitor/ARB unless creatinine rises >30% within 4 weeks 3
• Taper atenolol gradually if no specific cardiac indication exists (avoid abrupt cessation to prevent rebound hypertension or angina exacerbation) 1

Common Pitfalls to Avoid

• Don't reduce atenolol dose prematurely: At eGFR 45, the current dose is safe
• Don't continue beta-blocker monotherapy: This misses the kidney-protective benefits of RASi therapy that reduce mortality and CKD progression
• Don't stop RASi if creatinine rises <30%: Small increases are expected and acceptable 3
• Don't avoid RASi due to fear of hyperkalemia: This can be managed with dietary modification and potassium binders rather than stopping the drug 3
• Don't forget to continue RASi even if eGFR falls below 30 mL/min/1.73 m² 3

Monitoring Parameters

After transitioning therapy:

• BP and heart rate at each visit
• Serum creatinine and potassium 2-4 weeks after RASi initiation or dose change 3
• Annual monitoring of eGFR and albuminuria
• Assess for symptomatic hypotension or bradycardia