What Are The 5 Stages Of Kidney Failure? Detecting Each Stage Based On The GFR Test

According to the Centers for Disease Control and Prevention (CDC), about 37 million¹ people in the US have chronic kidney disease (CKD).

CKD is a common condition that predominantly affects older people. Anyone can get the disease, but it's most prevalent among African Americans. If not properly managed, CKD can worsen over time, resulting in kidney failure. 

CKD progresses in distinct stages, and treatments aim to slow progression and reduce the risk of complications. Since symptoms of the disease are often subtle in the early stages, many people with kidney disease don't know they have it.

What is chronic kidney disease?

CKD is a condition that results in the gradual loss of kidney function. Having CKD means your kidneys are damaged and cannot perform their tasks as efficiently as healthy kidneys.

Kidneys have various functions, including the clearing of waste through urine. When the kidneys aren’t functioning properly, waste can accumulate in the body, possibly leading to other health conditions, including high blood pressure (hypertension) and heart disease. These secondary conditions may develop slowly over time as your condition moves from one stage to the next. 

Early CKD detection will help ensure you receive the best care to slow progression and minimize complications. Each stage involves different tests and treatment options.

What are the stages of chronic kidney disease?

CKD is ranked from stage 1 to stage 5. Stage 1 is the closest to a healthy kidney, while stage 5 signifies kidney failure. Stages 1 to 3 are considered mild-to-moderate, while stages 4 and 5 are severe.  

Each stage of kidney disease has different symptoms and treatment options depending on the cause. Glomerular filtration rate (GFR) is a measure of how well your kidneys are filtering. Measuring GFR² (mGFR) is complicated and time-consuming. In most cases, a doctor will input results from a simple blood test into a mathematical formula to calculate the estimated glomerular filtration rate (eGFR) instead.

Kidneys have glomeruli, which are tiny filters that help remove waste from the blood. The results of a GFR or eGFR test describe how much filtration happens per minute. In stages 1 to 3 (early stages), your kidneys can still filter waste from your blood sufficiently, but in stages 4 and 5 (later stages), your glomeruli do not have sufficient filtration left. 

The average normal eGFR result is greater than 90mL/min/1.73m2. However, this cutoff is relatively arbitrary as GFR declines with age and is naturally lower in some people, even if they don’t have kidney disease. Besides the GFR test, your doctor will check your urine for:

• Blood

• Albumin is a protein that should be present in your blood but may show up in your urine if your kidneys aren’t filtering properly (this is called proteinuria) 

Additionally, your doctor may request other tests as they see fit to help identify the cause of your kidney disease. 

Stage 1 kidney failure

Stage 1 CKD is characterized by:

• Normal kidney function with evidence of kidney damage

• eGFR of 90ml/min/1.73m2 or higher (category G1)

• Protein in the urine for three or more months 

At this stage, your kidneys have mild damage and perform slightly less efficiently than healthy kidneys. However, since your kidneys are still functional, there may be no apparent signs of kidney damage.

Most patients with CKD don't know they have it until later stages. Typically, a person diagnosed in an early stage will find out they have kidney disease while being tested for another health condition, such as hypertension or diabetes, which are the leading causes of kidney disease. The tests that diagnose stage 1 CKD are:

• Urinalysis (urine tests)

• Blood (serum) tests

• Imaging tests (including, but not limited to, a CT scan or an MRI)

If you have stage 1 kidney failure, a test may reveal higher than normal levels of:

• Urea (an end product of protein metabolism)

• Proteins, particularly albumin, in the urine

• Creatinine (a waste product of the metabolism of muscle and protein)

Signs and symptoms of stage 1 kidney failure

At stage 1, you may not notice any obvious symptoms; however, certain signs indicate you may have kidney disease:

• High blood pressure (the relationship is bidirectional — CKD causes and is caused by high blood pressure)

• Urinary tract infections (UTIs)

• Protein in your urine

• Blood in your urine (hematuria)

• Swelling in your hands or feet

• Kidney damage visible in imaging tests

Treatments for stage 1 kidney failure 

CKD treatments aim to improve conditions that lead to kidney disease progression and minimize the risk of complications. Your doctor will likely prescribe blood pressure medication, such as ACE (angiotensin-converting enzyme) inhibitors or ARBs (angiotensin-II receptor blockers). Research³ shows that these medications help slow down kidney damage.

Other treatment options to help manage the condition and reduce kidney damage include:

• Statins

• Dapagliflozin⁴

• Controlling diabetes (if you have it)

• Controlling your blood pressure typically 

• Controlling your cholesterol levels 

• Regular checkups and tests

• Monitoring your GFR levels

• Taking all prescribed medications

Making healthy lifestyle changes is also essential in managing kidney disease. Your doctor may recommend:

• Exercising for at least 30 minutes five days per week

• Maintaining a healthy weight

• Quitting smoking (if you smoke)

• Planning a healthy diet

While kidney damage is most commonly irreversible, taking appropriate health measures can help slow the progression.

Stage 2 kidney failure

Stage 2 CKD is defined by:

• Mild impairment in kidney function

• eGFR of 60–89ml/min/1.73m2 (category G2)

• Protein in the urine for three or more months

Like stage 1, stage 2 CKD is associated with mild enough kidney function impairment that is often only detected during testing for other conditions. 

Moving from stage 1 to stage 2 CKD indicates your condition worsens. If you haven’t already, stage 2 may be a good time to speak with your doctor about better managing other conditions, such as diabetes and high blood pressure, that can accelerate progression. 

Signs and symptoms of stage 2 kidney failure

Many people with stage 2 CKD don't know they have it because the kidneys are still functioning well enough to prevent pronounced symptoms. However, a doctor may suspect stage 2 kidney failure if they detect any signs of stage 1 kidney failure alongside lower GFR values.

Complications of stage 2 kidney failure

Progression from stage 1 to stage 2 indicates a reduction in kidney functioning. At this stage, you may start to experience complications, particularly if your CKD is caused by high blood pressure. People with hypertension are more likely to experience new or recurrent cardiovascular events in stage 2 (and stage 3) CKD.  

Early intervention to manage other conditions can help reduce the risk of complications. 

Treatments for stage 2 kidney failure

Your doctor will use your eGFR to assess your CKD progression and decide if the treatments and lifestyle changes implemented in stage 1 are adequately effective. Your doctor may recommend sticking to your stage 1 plan or may recommend adjustments to further slow progression and lessen the likelihood of complications.

While your treatment plan for stage 2 CKD may look a lot like your stage 1 treatment plan, your doctor may add treatments not previously prescribed to slow progression. Recommended interventions are even more important in stage 2 because stage 3 kidney failure has more severe symptoms and is more likely to trigger complications. (More on that below.)

A healthy way of living and following your treatment plan will delay the progression of stage 2 CKD to stage 3.

Stage 3 kidney failure

Stage 3 CKD is characterized by:

• A moderate reduction in kidney functioning

• eGFR of 30–59ml/min/1.73m2 (category G3)

Stage 3 kidney failure is further divided into two subtypes, depending on eGFR results:

• Stage 3a with readings between 45–59ml/min/1.73m2

• Stage 3b with readings between 30–44ml/min/1.73m2

At this stage, your kidneys cannot filter waste products and fluids as well as in stage 1 or 2, but they still perform well enough that you likely won’t need dialysis. In stage 3, you’ll need regular blood work and monitoring to closely monitor progression and the factors that affect it. Any declines in eGFR indicate progression.

Signs and symptoms of stage 3 kidney failure

Stage 3 CKD is where most people start to notice clear symptoms, which may include:

• Fatigue

• Swelling in hands or feet

• Anorexia

• Trouble sleeping

• Muscle cramps

• Changes in urination frequency

• Dark or foamy urine

• Restless legs

• Lower back pain

• Dry, itchy skin

If your CKD wasn’t picked up in stage 1 or 2 through testing for other conditions, the symptoms you begin to experience in stage 3 might be the ones that encourage you to seek testing. 

Complications of stage 3 kidney failure

With reduced kidney function, you may experience complications, such as:

• Early bone disease

• Anemia

• Water retention

• Cardiovascular disease

•  High blood pressure

• Metabolic acidosis (a buildup of acid in the body)

• Nutritional issues

These complications indicate progression. However, it’s not too late to start making positive changes to slow further progression.

Treatments for stage 3 kidney failure

Treatments aim to improve control over underlying health conditions such as diabetes and hypertension and slow the progression of kidney damage. 

Treatments for stage 3 CKD include:

• Medication (for blood pressure, cholesterol, diabetes, and swelling (diuretics))

• Iron supplements to manage anemia

• Vitamin D and calcium supplements if your doctor recommends them

Your doctor may advise stopping over-the-counter medications that can worsen your condition. 

Alongside your treatment plan, your doctor may recommend lifestyle changes, such as:

• Quitting smoking

• Exercising regularly 

• Avoiding processed foods

• Adopting a healthy diet

Stage 4 kidney failure

People with stage 4 CKD have:

• Severe reduction in kidney functioning

• eGFR of 15-29ml/min/1.73m2 (category G4)

In stage 4, your kidneys work much less efficiently than healthy kidneys, and there will be more waste and fluid buildup.   

If you aren’t already working with a nephrologist (kidney specialist), your primary provider will refer you to one at this stage. Your doctor will typically refer you to a nephrologist when it’s possible that dialysis will soon become part of your treatment plan.

Signs and symptoms of stage 4 kidney failure

With severe kidney damage, you’ll likely notice some or all of the following symptoms:

• Swelling in the limbs

• Changes in urination habits

• Fatigue

• Lower back pain

• Muscle aches

• Decreased appetite 

• Feeling stomach sick

Your nephrologist and primary care provider can work with you to manage your symptoms as effectively as possible.

Complications of stage 4 kidney failure

Waste buildup and poor kidney function can cause or exacerbate other health conditions, such as:

• High blood pressure

• Anemia

• Bone disease

• Heart disease

• High potassium

• High phosphorus

• Metabolic acidosis (a buildup of acid in your body)

• Poor nutrition

• Increased risk of infection due to a weakened immune system

• Erectile dysfunction in men and low sexual desire in women

Work with your care team to minimize complications. Your doctors may be able to recommend treatments or lifestyle changes to improve your symptoms. 

Treatments for stage 4 kidney failure

At stage 4, you’ll need to visit your doctor more often to assess your disease’s progression.

Treatment plans in this stage focus on monitoring and managing your condition and slowing further damage. Along with the treatments outlined in stage 3, your doctor may recommend erythropoiesis-stimulating agents to treat anemia, if necessary.

Like in the previous stages, self-management is essential in stage 4 CKD. You can still slow progression at this later stage by taking medications as directed and maintaining a healthy lifestyle and healthy eating habits. 

Your treatment plan will also include:

• Quitting smoking

• Seeing your kidney specialist every three months or so

• Exercising for 30 minutes most days of the week

• Seeing a dietitian who can help you eat a kidney-friendly diet.

A kidney-friendly diet can slow damage by increasing foods that are easy on your kidneys and limiting those that cause your kidneys to struggle (leading to buildup). It also focuses on limiting foods that can cause or worsen high blood pressure and diabetes, which can accelerate CKD progression. It’s essential to note that people with CKD should be cautious of protein intake. In using protein, your body produces waste that goes to your kidneys for filtering. To protect your kidneys, your doctor or nutritionist may recommend a low-protein diet or one that favors lean proteins. 

You’ll need to discuss renal replacement therapies with your doctor at this stage. Options include:

• Dialysis

• A kidney transplant

• Supportive (palliative) care

Life expectancy for stage 4 CKD depends on numerous factors, including your age, underlying health disorders, and the effectiveness of your treatment plan.

Stage 5 kidney failure

Stage 5 CKD is marked by:

• Failure to function

• eGFR of less than 15ml/min/1.73m2 (category G5)

Kidney failure, or end-stage renal failure (ESRD), is the last stage of CKD. At this stage, you’ll need dialysis or a kidney transplant to live.

Signs and symptoms of stage 5 kidney failure

Since your kidneys can no longer eliminate waste products, there will be a toxin buildup, making you feel quite ill. Symptoms⁵ of stage 5 CKD include symptoms of earlier stages, as well as:

• Nausea or vomiting

• Headaches

• Difficulty breathing

• Difficulty thinking

• Urinating less often and a low volume of urine

• Numbness in hands or feet

• Changes in skin color

• Seizures

• Overactive reflexes

Complications of stage 5 kidney failure

Potential complications of stage 5 are widespread, affecting many parts of the body, and may include:

• Stomach and intestinal bleeding

• Fluid buildup in the lungs

• Nerve damage affecting the limbs 

• Liver damage or failure

• Heart attack and heart failure

• Reproductive issues

• Malnutrition

• Increased risk of infection due to decreased immune response

• Stroke

• Seizures

• Dementia

• Weakening of the bones due to imbalanced phosphorus and calcium 

Treatments for stage 5 kidney failure

There are two treatment options for end-stage CKD: 

Dialysis

When your kidneys fail to work, dialysis can remove the waste and excess fluids from your body. Additionally, dialysis helps maintain healthy blood pressure and desirable levels of potassium, sodium, and other minerals.

There are two main types of dialysis:

• Hemodialysis: A procedure that involves diverting your blood to a dialysis machine that removes waste and excess fluids.

• Peritoneal dialysis: A procedure that involves pumping dialysis fluid through a soft tube into your abdomen, allowing it to clean, and then removing it.

Dialysis will be a lifelong treatment for a person who doesn’t receive a kidney transplant. 

Hemodialysis treatment may take place at home or at a dialysis center. 

Peritoneal dialysis treatments can take place in any clean and dry space. Once the tube is placed during the initial appointment, you’ll do your treatments while you sleep or throughout the day, depending on your lifestyle.

Kidney transplant

A kidney transplant⁶ is a surgical procedure that involves the transplantation of a healthy donor kidney, which may come from a healthy living donor or someone who recently died and wanted to donate their organs. It’s considered the best option for someone with end-stage kidney failure. Typically, removing your kidneys won’t be necessary before transplanting a new one. 

Dialysis and kidney transplants don’t cure CKD. Your doctor will speak with you about continuing the treatments prescribed in the earlier stages, and you’ll still need to live a healthy lifestyle and see your doctor regularly.  

How quickly does CKD progress?

CKD doesn’t progress at the same rate for everyone with the condition. The rate of progression is influenced by certain factors, including:

• Uncontrolled high blood pressure

• Diabetes

• Heart failure

• Smoking

• Heroin use

• Not taking prescribed medicines

• Genetic predisposition

• Acute kidney injury (AKI)

In their study⁷ of adults with CKD, one team of researchers found certain conditions serve as strong predictors of fast progression, including:

• Anemia

• Heart failure

• High systolic blood pressure

• Proteinuria 

Participants with diabetes were more likely to experience rapid CKD progression (23.0% versus 15.3%), and those with diabetes who experienced fast progression were more likely to have one or more of the above-noted conditions.

The lowdown

Regardless of which stage of CKD you have, it’s essential you take the necessary steps to slow progression and minimize complications. Routine checkups and testing will help your doctor understand which treatments and therapies are working for you and help them identify areas that need improvement. 

If you suspect you may have early-stage kidney failure, see your doctor. Catching the condition early can improve symptoms, progression rate, and outcomes.