Dialysis Initiation in Chronic Kidney Disease
Dialysis is typically required at CKD Stage 5 (GFR <15 mL/min/1.73 m²), but the decision to initiate dialysis should be based primarily on clinical symptoms and signs of uremia rather than GFR threshold alone. 1, 2
CKD Stage Classification and Dialysis Threshold
- CKD Stage 5 is defined as GFR <15 mL/min/1.73 m², representing loss of more than 85% of kidney function and is the stage where renal replacement therapy becomes necessary. 3, 4
- Patients should receive education about kidney failure treatment options starting at CKD Stage 4 (GFR <30 mL/min/1.73 m²), at least 1 year before anticipated dialysis need. 1, 2
- Referral to nephrology must occur when patients reach Stage 4, as late referral (less than 1 year before RRT) is associated with worse outcomes. 3, 4
Clinical Indications That Mandate Dialysis Initiation
The decision to start dialysis should never be based solely on a GFR number—clinical assessment is paramount. 1, 5 The KDOQI guidelines explicitly state that dialysis initiation should be based on the following clinical criteria rather than a specific GFR level:
- Uremic symptoms: nausea, vomiting, anorexia, altered mental status, uremic pericarditis, or peripheral neuropathy 3, 2, 4
- Protein-energy wasting: progressive malnutrition despite dietary intervention 1, 2
- Volume overload: fluid overload unresponsive to diuretic therapy or refractory pulmonary edema 3, 2, 4
- Metabolic abnormalities: severe hyperkalemia unresponsive to medical therapy or severe metabolic acidosis that cannot be safely managed 1, 3
- Uremic bleeding: bleeding due to uremic platelet dysfunction 2
Evidence Against Early Dialysis Initiation
The landmark IDEAL trial demonstrated that early dialysis initiation (at eGFR >10 mL/min/1.73 m²) provides no morbidity or mortality benefit compared to waiting for clinical symptoms. 1, 5 This critical finding has been incorporated into current guidelines:
- In asymptomatic patients with Stage 5 CKD, dialysis may be safely delayed until eGFR is as low as 5-7 mL/min/1.73 m² with careful clinical follow-up and adequate patient education. 5
- Starting dialysis too early does not improve outcomes and may actually expose patients to dialysis-related complications prematurely. 4, 5
Special Considerations for Older and Frail Patients
Decision-making is substantially more complex for elderly patients with multiple comorbidities, where dialysis may worsen rather than improve quality of life. 2, 5
- Conservative management without dialysis is a valid and appropriate option that must be discussed with all CKD Stage 5 patients. 3, 4, 6
- This approach is particularly appropriate for patients with advanced age, frailty, multiple comorbidities, or those who decline dialysis after informed decision-making. 3, 4
- Recent studies in elderly patients show no advantage of dialysis over conservative management in terms of survival, hospitalization, or quality of life. 7
Critical Pitfalls to Avoid
- Never rely on serum creatinine alone—always calculate eGFR using validated equations (MDRD or CKD-EPI) that account for age, sex, race, and body size. 3, 4
- Do not initiate dialysis based on GFR threshold alone without clinical symptoms, as this does not improve outcomes. 3, 4, 5
- Creatinine-based eGFR formulae are particularly inaccurate in patients with ESRD, making clinical assessment even more critical. 5
- In patients with unusual creatinine generation (very muscular or malnourished), GFR should be estimated using methods independent of creatinine generation. 2
Treatment Options at Stage 5
When patients reach Stage 5, four primary options exist:
- Preemptive kidney transplantation: optimal choice for appropriate candidates, avoiding dialysis entirely 3
- Hemodialysis: most common modality, requires vascular access planning 6-8 months in advance 3
- Peritoneal dialysis: home-based therapy that preserves residual kidney function longer 3
- Conservative management: valid option focusing on symptom management without dialysis 3, 4, 6