SGLT2 Inhibitors in Kidney Disease: 2025 PLAB 2 Research Update

Introduction

The landscape of nephrology has been revolutionised by the emergence of SGLT2 inhibitors, with groundbreaking research in 2025 further solidifying their role in renal protection. For PLAB 2 candidates, understanding these recent advances is crucial, as they represent one of the most significant developments in modern medicine.

Mechanism of Action

SGLT2 inhibitors work by blocking the sodium-glucose co-transporter 2 in the proximal tubule of the kidney, leading to:

• Glycosuria: Excretion of excess glucose in urine

• Natriuresis: Increased sodium excretion

• Tubuloglomerular feedback: Reduction in intraglomerular pressure

2025 Research Updates

1. Renoprotective Effects Confirmed

The 2025 consensus statements from KDIGO (Kidney Disease: Improving Global Outcomes) have expanded recommendations for SGLT2 inhibitor use:

• CKD Stages 1-3: Recommended for patients with albuminuria

• CKD Stage 4: Now indicated in select patients with eGFR ≥20 ml/min/1.73m²

• Dialysis Patients: Ongoing trials show potential cardiovascular benefits

2. Finerenone Combination Therapy

Recent trials have demonstrated synergistic effects when combining SGLT2 inhibitors with finerenone (a non-steroidal MRA):

• Greater albuminuria reduction compared to monotherapy

• Cardiovascular outcome benefits preserved

• Safety profile remains acceptable

3. New Indications Approved 2025

The MHRA has approved SGLT2 inhibitors for:

• IgA Nephropathy: Based on the TESTING trial results

• Diabetic Kidney Disease: Expanded criteria for early intervention

• Heart Failure with Preserved Ejection Fraction (HFpEF): Renal-protective benefits confirmed

PLAB 2 Clinical Scenarios

Scenario 1: Diabetic Patient with CKD

A 55-year-old patient with Type 2 Diabetes and CKD Stage 3 (eGFR 45 ml/min) presents for review.

Management Approach:

• Continue SGLT2 inhibitor (canakinumab or empagliflozin)

• Monitor eGFR and potassium

• Aim for BP target <130/80 mmHg

• Consider finerenone if albuminuria persists

Scenario 2: Heart Failure Patient

A 68-year-old with HFpEF and eGFR 35 ml/min/1.73m².

Key Points:

• SGLT2 inhibitors now first-line

• Benefits seen even at lower eGFR

• Monitor for volume depletion

• Educate about genital mycotic infections

Side Effects to Counsel Patients About

Important Considerations for PLAB 2

1. eGFR Thresholds: Remember the prescribing limits (typically eGFR ≥20-25 ml/min for most SGLT2i)

2. Drug Interactions:

   • Loop diuretics: Increased risk of dehydration

   • Insulin/secretagogues: Hypoglycaemia risk

3. Monitoring Parameters:

   • eGFR: Check at baseline, 2-4 weeks, then 3-monthly

   • Potassium: Monitor especially with ACEi/ARB

   • Blood pressure: Risk of hypotension

4. Patient Education Points:

   • Stop SGLT2i before planned surgery

   • Hold during acute illness

   • Pregnancy and breastfeeding contraindicated

Summary

The 2025 updates have cemented SGLT2 inhibitors as cornerstone therapy in nephrology. For PLAB 2 success, understanding their:

• Renal protective mechanisms

• Expanded indications

• Monitoring requirements

• Patient counselling points

is essential. These agents represent the paradigm shift towards multi-organ protection in cardiometabolic disease.

Stay tuned for more PLAB 2 updates!