What are the stages of chronic kidney disease (CKD) and their corresponding treatment plans?

Chronic Kidney Disease Stages and Treatment

Chronic kidney disease is classified into five stages based on GFR, with Stage 1 (GFR ≥90 mL/min/1.73 m² with kidney damage) through Stage 5 (GFR <15 mL/min/1.73 m² or dialysis), and treatment must be tailored to each stage with early stages focusing on risk factor modification and later stages requiring preparation for kidney replacement therapy. 1

CKD Staging System

Stage Definitions by GFR

• Stage 1: GFR ≥90 mL/min/1.73 m² with evidence of kidney damage (albuminuria, proteinuria, or structural abnormalities on imaging) 1
• Stage 2: GFR 60-89 mL/min/1.73 m² with evidence of kidney damage 1
• Stage 3a: GFR 45-59 mL/min/1.73 m² (moderate decrease in kidney function) 1
• Stage 3b: GFR 30-44 mL/min/1.73 m² (moderate to severe decrease) 1
• Stage 4: GFR 15-29 mL/min/1.73 m² (severe decrease in kidney function) 1
• Stage 5: GFR <15 mL/min/1.73 m² or dialysis (kidney failure) 1

Critical Diagnostic Requirements

• All abnormalities must persist for at least 3 months to distinguish chronic from acute kidney disease 1
• Stages 1 and 2 require evidence of kidney damage (such as albuminuria ≥30 mg/g) for diagnosis, while stages 3-5 can be diagnosed based on GFR alone 1
• Use the CKD-EPI equation for GFR estimation as it demonstrates less bias than MDRD, especially at GFR ≥60 mL/min/1.73 m² 1

Complete Risk Stratification

• Always classify using the complete CGA system (Cause, GFR category, Albuminuria category), not GFR alone 1
• Albuminuria categories: A1 (<30 mg/g), A2 (30-300 mg/g), A3 (>300 mg/g) 1
• Measure albumin-to-creatinine ratio (ACR) on a single urine sample rather than 24-hour collection 1

Stage-Specific Treatment Plans

Stages 1-2: Early CKD Management

Primary focus is on halting progression and cardiovascular risk reduction 2

Core Interventions

• Screen for and aggressively treat underlying causes, particularly diabetes and hypertension 2
• Blood pressure control with target <130/80 mmHg 2
• ACE inhibitors or ARBs for patients with albuminuria ≥30 mg/g, especially in diabetic kidney disease 2
• Glycemic control in diabetic patients with HbA1c target ≤7% (individualized based on comorbidities) 2
• Initiate statin therapy for cardiovascular risk reduction in adults ≥50 years with eGFR ≥60 mL/min/1.73 m² 2

Monitoring Strategy

• Annual monitoring of kidney function and albuminuria 1
• Serial eGFR and ACR measurements to track progression 3

Stage 3: Moderate CKD Management

Begin intensive monitoring for complications and estimate progression rate 1

Stage 3a (GFR 45-59)

• Continue all Stage 1-2 interventions 2
• Initiate statin or statin/ezetimibe combination in all adults ≥50 years, regardless of baseline lipid levels 2
• Begin monitoring for anemia, bone mineral disorders, and metabolic acidosis 2
• Follow-up with biological control 2-4 times per year based on severity 1

Stage 3b (GFR 30-44)

• All Stage 3a interventions plus more frequent monitoring 1
• Address metabolic acidosis as it increases protein breakdown and accelerates progression 2
• Increased surveillance for complications as risk rises significantly when GFR falls below 45 mL/min/1.73 m² 1

Stage 4: Severe CKD Management

Intensive management of complications and preparation for kidney replacement therapy 1

Key Actions

• Mandatory nephrology referral for all Stage 4 patients (GFR <30 mL/min/1.73 m²) 2
• Continue cardiovascular risk reduction with statins and blood pressure management 2
• Monitor hemoglobin levels and consider iron supplementation for anemia 2
• Manage hyperkalemia, metabolic acidosis, hyperphosphatemia, vitamin D deficiency, and secondary hyperparathyroidism 4
• Treat symptomatic hyperuricemia (gout) with xanthine oxidase inhibitors 2
• Begin patient education about kidney replacement therapy options 5

Complications Management

• Hypertension prevalence approaches 80% at this stage 1
• Anemia becomes increasingly prevalent 1
• Multiple complications increase substantially when GFR falls below 30 mL/min/1.73 m² 1

Stage 5: Kidney Failure Management

Kidney replacement therapy required when uremic symptoms develop 1

Treatment Options

• Initiate dialysis when uremic symptoms develop or GFR falls below 10-15 mL/min/1.73 m² 2
• Hemodialysis is typically performed 3-4 hours three times weekly as the standard modality 2
• Kidney transplantation should be pursued when appropriate 2
• Continue cardiovascular risk reduction strategies including statins and blood pressure management 2

Common Pitfalls to Avoid

• Never delay nephrology referral beyond Stage 4 (GFR <30 mL/min/1.73 m²) as late referral worsens outcomes 2, 5
• Do not classify using GFR alone—always include cause and albuminuria category for complete risk stratification 1
• Avoid inadequate monitoring—regular assessment of kidney function, albuminuria, and complications is essential 2
• Do not rely on serum creatinine alone—use GFR estimation equations that account for age, sex, race, and body size 1
• Never assume GFR and albuminuria correlate—both parameters must be monitored independently as there is no correlation between GFR and albuminuria progression 1
• Avoid nephrotoxins including NSAIDs and adjust drug dosing for many antibiotics and oral hypoglycemic agents 4