What is the Glomerular Filtration Rate (GFR) indicative of end-stage renal disease?

Glomerular Filtration Rate (GFR) for End Stage Renal Disease

End-stage renal disease (ESRD) is defined by a GFR less than 15 mL/min/1.73 m² or the need for kidney replacement therapy (dialysis or transplantation). 1

Definition and Classification

• ESRD corresponds to Stage 5 Chronic Kidney Disease (CKD) in the National Kidney Foundation Kidney Disease Outcomes Quality Initiative (K/DOQI) classification system 1
• Kidney failure is defined as either:
  • GFR < 15 mL/min/1.73 m² (accompanied in most cases by signs and symptoms of uremia) 1
  • Need to start kidney replacement therapy (dialysis or transplantation) 1

Important Distinctions

• Kidney failure is not synonymous with ESRD 1
• ESRD is an administrative term in the United States that indicates a patient is treated with dialysis or transplantation, which is the condition for payment by the Medicare ESRD Program 1
• The classification of ESRD does not include patients with kidney failure who are not treated with dialysis and transplantation 1
• Approximately 98% of patients with kidney failure in the United States begin dialysis when their GFR is < 15 mL/min/1.73 m² 1

Clinical Implications and Management

• When patients reach CKD stage 5 (estimated GFR < 15 mL/min/1.73 m²), nephrologists should evaluate the benefits, risks, and disadvantages of beginning kidney replacement therapy 1
• Patients who reach CKD stage 4 (estimated GFR < 30 mL/min/1.73 m²) should receive timely education about kidney failure and treatment options 1
• Treatment options include:
  • Kidney transplantation
  • Peritoneal dialysis
  • Hemodialysis (home or in-center)
  • Conservative treatment 1

GFR Estimation and Monitoring

• GFR should be estimated using validated equations (such as MDRD or CKD-EPI) or by measurement of creatinine and urea clearances, not simply by measurement of serum creatinine and urea nitrogen 1
• Renal replacement therapy should be considered in patients with eGFR < 30 mL/min/1.73 m² 1
• Dialysis therapy and transplantation should be initiated in patients with eGFR < 15 mL/min/1.73 m² or when clinically indicated 1

Risk Assessment and Prognosis

• A decline in estimated GFR is strongly associated with the risk of ESRD and mortality 2
• For patients with a baseline eGFR of 35 mL/min/1.73 m², the 10-year risk of ESRD is:
  • 99% for an eGFR decline of 57%
  • 83% for an eGFR decline of 40%
  • 64% for an eGFR decline of 30%
  • 18% for no change in eGFR 2

Important Considerations

• Both lower eGFR and higher albuminuria independently predict mortality and ESRD among individuals with CKD 3
• The association between eGFR and outcomes is stronger for ESRD than for mortality 3
• For some patients, conservative therapy without dialysis or transplantation may be the appropriate option 1
• Protein intake should be approximately 0.8 g/kg/day in patients with diabetic kidney disease 1

Clinical Pitfalls to Avoid

• Do not rely solely on serum creatinine measurements to estimate GFR, as this can lead to inaccurate assessment of kidney function 1
• Be aware that HbA1c accuracy may be affected at eGFR < 30 mL/min/1.73 m², particularly in patients receiving dialysis and erythropoietin-stimulating agents 1
• Recognize that normal values of eGFR (> 60 mL/min/1.73 m²) overlap with values in stages 1 and 2 of CKD, thus an eGFR greater than 60 mL/min/1.73 m² does not exclude kidney disease 4