The 5 Stages of Chronic Kidney Disease (CKD)
Chronic Kidney Disease is a serious, progressive condition where the kidneys gradually lose their ability to filter waste and excess fluid from the blood. The five stages are determined by a blood test that measures your estimated Glomerular Filtration Rate (eGFR), which indicates how well your kidneys are functioning. The higher the eGFR, the better your kidney function.
Stage 1: Kidney Damage with Normal or High GFR
In this initial stage, your eGFR is 90 mL/min or higher. You typically won't experience any symptoms, and your kidneys are still working well. However, there is evidence of kidney damage, such as protein in your urine (albuminuria), or physical abnormalities like kidney stones or cysts. The primary focus of management is controlling underlying conditions like high blood pressure or diabetes to prevent progression.
Stage 2: Mild Loss of Kidney Function
With an eGFR between 60 and 89 mL/min, your kidney function is mildly reduced. As with Stage 1, symptoms are often absent, and most people are unaware they have CKD. A doctor will continue to monitor your eGFR and urine for signs of damage. Early detection and aggressive management of risk factors are crucial at this stage to prevent further deterioration.
Stage 3: Moderate Loss of Kidney Function
This stage is further broken down into two sub-stages:
- Stage 3A: eGFR is 45-59 mL/min.
- Stage 3B: eGFR is 30-44 mL/min. Symptoms may begin to appear in Stage 3, including fatigue, swelling in hands and feet (edema), and changes in urination. As the waste products build up, your doctor will likely prescribe medication to manage blood pressure and other related complications.
Stage 4: Severe Loss of Kidney Function
At this point, your eGFR is between 15 and 29 mL/min. The severe decline in function means your kidneys are struggling to filter waste, and more pronounced symptoms are likely. These can include nausea, vomiting, a metallic taste in the mouth, and nerve problems. Treatment plans often include preparations for kidney replacement therapy, such as dialysis or a transplant.
Stage 5: Kidney Failure (End-Stage Renal Disease)
This is the most advanced stage, with an eGFR of less than 15 mL/min. Your kidneys have failed or are very close to failing completely. Without treatment, life-threatening complications can occur. At this stage, patients require kidney replacement therapy, which includes dialysis or a kidney transplant.
Causes and Risk Factors
Diabetes and high blood pressure are the two most common causes of CKD in the US, accounting for the majority of cases. High blood sugar in people with diabetes can damage the delicate filtering units in the kidneys over time. Similarly, uncontrolled high blood pressure can damage the small blood vessels in the kidneys, hindering their function. Other risk factors include:
- Heart disease
- Family history of kidney disease
- Older age
- Being overweight or obese
- Smoking
Diagnosis and Management
Diagnosing CKD early is critical for slowing its progression. A doctor will typically perform two simple tests:
- eGFR: A blood test to calculate your estimated Glomerular Filtration Rate.
- uACR: A urine albumin-to-creatinine ratio test to check for protein in your urine.
For management, doctors focus on treating the underlying cause, controlling symptoms, and preventing complications. Lifestyle modifications play a major role in managing CKD and include:
- Adopting a healthy diet, often low in sodium and adjusted for protein and potassium.
- Exercising regularly to maintain a healthy weight.
- Quitting smoking.
- Limiting alcohol intake.
Comparison of CKD Stages
| Stage | eGFR Range (mL/min) | Common Symptoms | Treatment & Management Focus |
|---|---|---|---|
| 1 | $\geq 90$ | None; normal kidney function | Control underlying conditions like diabetes/HBP; prevent progression |
| 2 | $60-89$ | None or very mild | Ongoing monitoring of kidney function; managing risk factors |
| 3 | $30-59$ | Fatigue, swelling, changes in urination | Symptom management; medication to control HBP and other issues |
| 4 | $15-29$ | Nausea, vomiting, nerve problems, severe fatigue | Preparations for kidney replacement therapy (dialysis or transplant) |
| 5 | $< 15$ | Advanced symptoms (all of the above plus more) | Immediate kidney replacement therapy (dialysis or transplant) or palliative care |
Conclusion
Understanding what disease has 5 stages is critical for both early detection and effective management. Chronic Kidney Disease, a condition affecting millions, can be managed and its progression slowed, especially when caught in its early stages. While end-stage kidney failure (Stage 5) requires intensive therapy like dialysis or transplant, lifestyle adjustments and medical care can significantly improve quality of life throughout the journey. By proactively managing risk factors and adhering to treatment plans, individuals can live full lives even with CKD.
For more information on preventing chronic kidney disease and maintaining kidney health, consult resources from the Centers for Disease Control and Prevention (CDC).
