What medication should be added to reduce cardiovascular risk in a patient with type 2 diabetes, CKD, and proteinuria, already on lisinopril, metformin, and calcium carbonate?

Medication Recommendation for Cardiovascular Risk Reduction in Type 2 Diabetes with CKD

Losartan should be added to this patient's medication regimen to reduce cardiovascular risk and provide renal protection given her type 2 diabetes, stage 3 CKD, and significant albuminuria.

Patient Assessment

This 71-year-old woman presents with:

• Type 2 diabetes
• Stage 3 chronic kidney disease (baseline GFR 53, now deteriorated to GFR calculated from creatinine 2.2)
• Significant albuminuria (urine albumin-to-creatinine ratio 310 mg/g)
• Hypertension (currently on lisinopril)
• HbA1c 6.9% (controlled diabetes)
• Current medications: lisinopril, metformin, calcium carbonate

Rationale for Losartan Addition

Albuminuria and Renal Protection

• The patient has significant albuminuria (UACR 310 mg/g) which indicates kidney damage and increased cardiovascular risk
• Guidelines strongly recommend RAAS blockers for patients with diabetes, hypertension, eGFR <60 mL/min/1.73 m², and UACR ≥300 mg/g Cr 1
• Losartan has demonstrated significant renal benefits in patients with type 2 diabetes and nephropathy, with a 28% risk reduction for end-stage renal disease and 25% reduction in doubling of serum creatinine 2

Cardiovascular Risk Reduction

• Losartan reduced hospitalization for heart failure by 32% in patients with type 2 diabetes and nephropathy 2
• ARBs are recommended in patients with diabetes and CAD to reduce cardiovascular events 1
• The patient's combination of diabetes, CKD, and albuminuria places her at very high cardiovascular risk

Comparison with Other Options

1. Candesartan vs. Losartan:

   • Both are ARBs, but losartan has specific evidence in diabetic nephropathy 2
   • No compelling evidence to choose candesartan over losartan for this specific patient profile

2. Hydrochlorothiazide:

   • While diuretics are important in CKD, this patient already has worsening kidney function
   • Guidelines prioritize RAAS blockers over diuretics for patients with albuminuria 1
   • Adding an ARB would provide more cardiovascular and renal protection than a diuretic alone

3. Clonidine:

   • Not recommended as first-line therapy for cardiovascular risk reduction in diabetes with CKD
   • No evidence supporting superior cardiovascular or renal outcomes compared to RAAS blockers

Dual RAAS Blockade Consideration

The patient is already on lisinopril (ACE inhibitor), and adding losartan would create dual RAAS blockade. This requires careful consideration:

• While dual RAAS blockade is generally not recommended due to increased risk of adverse events 1, this patient has:

  • Significant albuminuria (>300 mg/g)
  • Worsening kidney function
  • High cardiovascular risk

• The approach should be:

  1. Add losartan at a low dose
  2. Monitor renal function and potassium closely
  3. Consider discontinuing lisinopril and optimizing losartan dose if adverse effects occur

Implementation Plan

1. Start losartan at 25mg daily (lower dose due to CKD)
2. Check serum creatinine and potassium within 1-2 weeks
3. If tolerated, titrate to target dose of 50-100mg daily
4. Monitor for:
   • Hyperkalemia
   • Further decline in renal function
   • Hypotension

Important Cautions

• Hyperkalemia risk: Monitor potassium levels closely when using dual RAAS blockade
• Acute kidney injury: The recent deterioration in renal function requires close monitoring
• Volume status: Ensure patient is not volume depleted before initiating therapy
• Metformin: Current guidelines allow continued use of metformin with eGFR >30 mL/min/1.73m² 1, 3, but monitor renal function closely

Alternative Approach if Dual RAAS Blockade Not Tolerated

If the patient cannot tolerate dual RAAS blockade:

1. Discontinue lisinopril
2. Optimize losartan dosing
3. Consider adding an SGLT2 inhibitor if renal function stabilizes, as these have demonstrated cardiovascular and renal benefits in patients with type 2 diabetes and CKD 1