Understanding Kidney Disease: Causes, Stages, and Management

Medically Reviewed by Dr. Oluwakemi Balogun (Kemi), MD — Medhaven Health

Last updated: September 2025

The kidneys play a vital role in filtering waste, balancing fluids, regulating blood pressure, and producing hormones essential for bone health and red blood cell production. When kidney function begins to decline, it can lead to chronic kidney disease (CKD)—a progressive, long-term condition that affects millions of people worldwide.

Chronic kidney disease is often silent in the early stages but can lead to severe complications if left unmanaged. By understanding the causes, recognizing the stages, and implementing timely interventions, patients can delay or even prevent the progression to end-stage renal disease (ESRD)—also known as Stage 5 CKD.

What Is Chronic Kidney Disease (CKD)?

CKD is defined as a gradual loss of kidney function over a period of months or years. It is diagnosed when there is evidence of kidney damage (such as protein in the urine) or reduced kidney function (measured by eGFR—estimated glomerular filtration rate) for three months or longer.

The condition progresses through five stages, ranging from mild (Stage 1) to complete kidney failure (Stage 5). Early detection and management are critical to slowing its progression and improving quality of life.

Common Causes of Kidney Disease

1. Diabetes (Type 1 and 2)

High blood sugar can damage the tiny blood vessels in the kidneys, leading to diabetic nephropathy.

2. Hypertension (High Blood Pressure)

Chronic high blood pressure can cause arteries around the kidneys to narrow, weaken, or harden.

3. Glomerulonephritis

Inflammation of the kidney’s filtering units (glomeruli), which can be acute or chronic.

4. Polycystic Kidney Disease (PKD)

A genetic condition that causes fluid-filled cysts to form in the kidneys, reducing function over time.

5. Recurrent Urinary Tract Infections or Obstructions

These can lead to scarring and damage if left untreated.

6. Autoimmune Diseases

Conditions like lupus can target and inflame kidney tissue.

7. Overuse of NSAIDs or Certain Medications

Long-term use of pain relievers like ibuprofen can damage the kidneys.

Stages of Kidney Disease and Their Management

CKD is categorized into five stages, determined by the glomerular filtration rate (GFR)—a measure of how well the kidneys are filtering blood.

Stage 1: Kidney Damage with Normal Function (GFR ≥ 90 mL/min)

Description: Kidneys are functioning normally, but there may be signs of damage such as proteinuria (protein in the urine) or structural abnormalities.
Symptoms: Usually none. Lab tests may reveal slight abnormalities.
Management:

• Control underlying conditions (e.g., diabetes, hypertension)

• Monitor kidney function with routine lab work

• Encourage healthy lifestyle: low-sodium diet, exercise, hydration

• Avoid nephrotoxic medications (e.g., NSAIDs)

• Begin working with a nephrologist if at high risk

Stage 2: Mild Reduction in Kidney Function (GFR 60–89 mL/min)

Description: Slight decrease in filtering capacity, but still often asymptomatic.
Symptoms: Minimal or no symptoms.
Management:

• Maintain good blood pressure (<130/80 mmHg)

• Keep blood sugar within target range

• Regular urine and blood tests

• Monitor cholesterol and maintain a kidney-friendly diet

• Early referral to a nephrologist may be helpful

Stage 3: Moderate Reduction in Kidney Function (GFR 30–59 mL/min)

Description: More noticeable decline in kidney function. This stage is often when CKD is first diagnosed.
Symptoms:

• Fatigue

• Swelling (edema) in legs and ankles

• Changes in urination

• Back pain
  Management:

• Work closely with a nephrologist

• Monitor and manage anemia, electrolyte imbalances (e.g., potassium, phosphorus), and bone health

• Begin dietary adjustments: restrict sodium, potassium, and phosphorus intake

• Monitor for complications like high parathyroid hormone levels

• Consider starting medications to manage phosphorus or vitamin D

Stage 4: Severe Reduction in Kidney Function (GFR 15–29 mL/min)

Description: Kidneys are significantly damaged and functioning at a severely reduced level.
Symptoms:

• Worsening fatigue

• Nausea

• Muscle cramps

• Swelling

• Loss of appetite

• Sleep disturbances
  Management:

• Intensified monitoring of labs and symptoms

• Begin discussions on renal replacement therapy (dialysis or transplant)

• Refer to a renal dietitian for detailed dietary guidance

• Evaluate and treat metabolic acidosis, anemia, and bone-mineral disorders

• Patient education on dialysis modalities (hemodialysis vs. peritoneal)

• Prepare vascular access (fistula) if dialysis is anticipated

Stage 5: End-Stage Renal Disease (GFR < 15 mL/min)

Description: Kidney function is extremely low or absent. Dialysis or transplant is required to sustain life.
Symptoms:

• Severe fatigue

• Nausea and vomiting

• Swelling in limbs and face

• Difficulty breathing

• Confusion or cognitive decline

• Urine output may decrease significantly
  Management:

Dialysis Options

• Hemodialysis: Blood is filtered using a dialysis machine 3–4 times a week.

• Peritoneal Dialysis: Uses the lining of the abdomen to filter blood via a catheter and dialysate fluid.

Kidney Transplant

• A donor kidney (living or deceased) replaces the function of the failed kidneys.

• Requires lifelong immunosuppressant therapy.

Conservative (Non-Dialysis) Management

• For patients who opt not to pursue dialysis or transplant, symptom control and quality-of-life support are emphasized, often in collaboration with palliative care.

Lifestyle and Support Strategies for CKD at All Stages

1. Diet and Nutrition

• Limit protein intake (especially in advanced stages)

• Avoid high-potassium foods (bananas, oranges, tomatoes)

• Limit phosphorus (dairy, nuts, processed foods)

• Reduce sodium (no more than 2,000 mg/day)

2. Fluid Management

• May need to limit fluids as disease progresses to reduce swelling and hypertension

3. Medication Management

• Avoid nephrotoxic drugs

• Dose adjustments may be necessary based on kidney function

4. Blood Pressure Control

• Target: Below 130/80 mmHg

• ACE inhibitors or ARBs are often first-line unless contraindicated

5. Glycemic Control in Diabetics

• Keep HbA1c around 7% to slow kidney damage

6. Mental Health Support

• Living with CKD can be emotionally challenging. Counseling and support groups can improve coping.

Q&A: Common Kidney Disease Concerns

Q: Can kidney disease be cured?
A: While chronic kidney disease is not reversible, its progression can be slowed or even halted with early intervention, proper treatment, and lifestyle changes.

Q: Do all patients with CKD end up on dialysis?
A: No. Many people with early or moderate CKD never require dialysis. Proper management can keep the disease stable for many years.

Q: Is it safe to exercise with kidney disease?
A: Yes. Gentle exercise like walking, swimming, or yoga is recommended. It can help with blood pressure control, mood, and weight management.

Q: How do I know when it’s time to start dialysis?
A: Symptoms like persistent nausea, extreme fatigue, swelling, and lab markers such as GFR < 15 or high potassium levels may indicate the need. Your nephrologist will guide you through this transition.

Conclusion: Proactive Care Can Preserve Kidney Health

Kidney disease is a serious but manageable condition when caught early and treated appropriately. With regular monitoring, medical guidance, and lifestyle modifications, individuals living with CKD can maintain a high quality of life for many years. For those progressing to Stage 5, options like dialysis and transplant can continue to provide life-sustaining treatment and hope.

At MedHaven Health, we are committed to helping patients at all stages of kidney disease receive the education, resources, and support they need. Our collaborative approach includes personalized care plans, routine monitoring, and partnerships with nephrology specialists when needed.