Understanding the 5 Stages of Chronic Kidney Disease (CKD): A Comprehensive Guide to Progression, Symptoms, and Treatment Options
What Is Chronic Kidney Disease (CKD)?
Chronic Kidney Disease—formerly referred to as chronic glomerulonephritis or chronic nephritis—is a progressive, long-term condition characterized by gradual loss of kidney function over time. Unlike acute kidney injury, CKD develops silently, often without noticeable symptoms in its early phases. That's why healthcare professionals rely on standardized staging systems, primarily based on the estimated Glomerular Filtration Rate (eGFR), to assess kidney health, guide monitoring, and determine appropriate interventions.
The 5-Stage CKD Classification System
Established by the National Kidney Foundation's Kidney Disease: Improving Global Outcomes (KDIGO) guidelines, the CKD staging framework uses eGFR (measured in mL/min/1.73 m²) alongside markers of kidney damage—such as persistent proteinuria, structural abnormalities, or imaging findings—to classify disease severity. Here's what each stage means:
Stage 1 CKD: Kidney Damage with Normal or High eGFR
eGFR ≥ 90 mL/min/1.73 m². At this stage, kidney function appears normal or even elevated—but signs of damage (e.g., albuminuria, abnormal imaging, or biopsy findings) are present. Early detection is critical: lifestyle modifications—including blood pressure control, diabetes management, reduced sodium intake, and avoidance of nephrotoxic medications—can significantly slow progression.
Stage 2 CKD: Mild Decline in Kidney Function
eGFR 60–89 mL/min/1.73 m². While still considered "mild," this stage signals the beginning of measurable functional decline. Patients may remain asymptomatic but benefit from regular monitoring (e.g., annual eGFR and urine albumin-to-creatinine ratio tests), cardiovascular risk assessment, and personalized nutrition counseling with a registered dietitian specializing in renal health.
Stage 3 CKD: Moderate Loss of Function—Split into 3a and 3b
eGFR 30–59 mL/min/1.73 m² (Stage 3a: 45–59; Stage 3b: 30–44). This is often when symptoms like fatigue, mild swelling, changes in urination patterns, or difficulty concentrating begin to emerge. Complications such as anemia, early bone mineral disorders, and hypertension become more common—making multidisciplinary care essential. Referral to a nephrologist is strongly recommended at Stage 3b to optimize long-term outcomes.
Stage 4 CKD: Severe Kidney Impairment
eGFR 15–29 mL/min/1.73 m². Kidney function is significantly compromised, and complications intensify—including fluid retention, electrolyte imbalances (e.g., hyperkalemia), metabolic acidosis, and worsening anemia. This stage demands proactive planning: patients should begin education about kidney replacement therapy options, including hemodialysis, peritoneal dialysis, and preemptive kidney transplantation. Vascular access planning and dietary adjustments (e.g., controlled phosphorus and potassium intake) are also prioritized.
Stage 5 CKD: End-Stage Renal Disease (ESRD)
eGFR < 15 mL/min/1.73 m²—or kidney failure requiring renal replacement therapy. At this point, the kidneys can no longer sustain basic bodily functions. Without intervention, life-threatening complications arise rapidly. Treatment focuses on either dialysis (hemodialysis or peritoneal dialysis) or kidney transplantation. Transplantation offers the best long-term survival and quality-of-life outcomes—when medically appropriate and accessible—and should be discussed well before reaching Stage 5.
Why Staging Matters Beyond Diagnosis
CKD staging isn't just clinical shorthand—it directly influences screening frequency, medication choices (e.g., avoiding certain NSAIDs or adjusting drug dosages), insurance coverage for specialist visits, and eligibility for transplant evaluation. Importantly, many people with early-stage CKD never progress to ESRD—especially with consistent, evidence-based care and patient empowerment.
Take Action Early—Your Kidneys Can't Wait
Because CKD is often symptomless until advanced, routine blood and urine testing—particularly for those with diabetes, high blood pressure, family history of kidney disease, or age over 60—is vital. Don't wait for warning signs. Talk to your primary care provider today about checking your eGFR and urine albumin levels. With timely diagnosis and tailored support, you can protect your kidney health for years to come.