Is it reasonable to start a Sodium-Glucose Cotransporter 2 (SGLT2) inhibitor in a patient with stage 3b chronic kidney disease (CKD) who is optimized on diabetes and hypertension care?

SGLT2 Inhibitors in Stage 3b CKD: Appropriate and Recommended

Yes, it is strongly recommended to start an SGLT2 inhibitor in your patient with stage 3b kidney disease who is optimized on diabetes and hypertension care. 1

Evidence-Based Rationale

The 2024 KDIGO guidelines explicitly recommend SGLT2 inhibitors for patients with CKD and eGFR ≥20 ml/min/1.73 m², regardless of diabetes status 1. This recommendation carries the highest level of evidence (1A), indicating strong confidence in the mortality and morbidity benefits.

Key points supporting this decision:

• SGLT2 inhibitors provide kidney and cardiovascular protection independent of their glucose-lowering effects 1
• The benefits extend to patients with eGFR as low as 20 ml/min/1.73 m² 1
• Once initiated, SGLT2 inhibitors can be continued even if eGFR falls below 20 ml/min/1.73 m² (unless not tolerated or kidney replacement therapy is initiated) 1

Implementation Algorithm

1. Verify eligibility: Confirm eGFR ≥20 ml/min/1.73 m² (stage 3b is 30-44 ml/min/1.73 m²)

2. Select appropriate SGLT2 inhibitor:

   • Prioritize agents with documented kidney or cardiovascular benefits 1
   • Consider specific eGFR thresholds for each agent:
     • Dapagliflozin: Can initiate at eGFR ≥25 ml/min/1.73 m² 1
     • Canagliflozin: Maximum 100 mg daily for eGFR 30-44 ml/min/1.73 m² 1
     • Empagliflozin: 10 mg daily for eGFR 30-44 ml/min/1.73 m² 1

3. Assess volume status and medication adjustments:

   • If patient is on diuretics, consider decreasing the dose before starting SGLT2i 1
   • Educate about symptoms of volume depletion and hypotension 1

4. Anticipate and manage initial eGFR changes:

   • Expect a reversible decrease in eGFR after starting therapy 1
   • This initial drop is generally not an indication to discontinue therapy 1
   • Follow up to reassess volume status and kidney function 1

Important Safety Considerations

1. Temporarily withhold SGLT2i during:

   • Prolonged fasting
   • Surgery or perioperative periods
   • Critical medical illness
   • Acute illness with risk of dehydration 1

2. Monitor for potential adverse effects:

   • Genital mycotic infections (more common in women) 1, 2
   • Euglycemic ketoacidosis (especially in insulin-dependent patients) 1, 2
   • Volume depletion symptoms 1, 2

3. Patient education:

   • Implement "sick day protocol" (temporarily withhold during illness) 1
   • Maintain adequate hydration 1
   • Report symptoms of urinary tract infections promptly 2

Long-term Benefits

The Cochrane systematic review (2024) found that SGLT2 inhibitors in CKD patients with diabetes:

• Decrease all-cause mortality (RR 0.85,95% CI 0.78-0.94)
• Reduce cardiovascular death (RR 0.83,95% CI 0.74-0.93)
• Decrease kidney failure risk (RR 0.70,95% CI 0.62-0.79) 3

These benefits are seen even in patients with moderate-to-severe renal impairment, with studies showing improvements in annual eGFR decline and reduction in proteinuria 4.

Conclusion

For your patient with stage 3b CKD who is already optimized on diabetes and hypertension management, adding an SGLT2 inhibitor is not only reasonable but strongly recommended based on current guidelines. The benefits for kidney protection, cardiovascular risk reduction, and overall mortality significantly outweigh the potential risks when appropriate monitoring and patient education are implemented.