Kidney disease stages: 1 to 5 listed by eGFR

CKD stages 1 to 5 based on eGFR

In the early stages of CKD (stages 1 to 3), your kidneys are still largely functional. In later stages (stages 4 and 5), your kidneys have to work harder to filter blood and may even stop working.

Staging CKD is important because it informs the treatment plan and indicates which measures to use based on the eGFR calculation and the rate at which eGFR declines over time.

Stage 1 CKD

With stage 1 chronic kidney disease, the damage to your kidneys is mild. For this reason, you may not have any symptoms.

You will invariably have an increased amount of protein in your urine (proteinuria). This is because damaged glomeruli allow more protein to escape into your urine rather than being filtered and returned to the bloodstream.

Typically, there are no symptoms associated with stage 1 CKD. Although some changes may be seen on ultrasound or in urine tests, they may not cause observable symptoms. The only exception is foamy urine caused by excessive amounts of a protein called albumin in your urine.

Treatment in stage 1 is largely focused on managing the underlying cause of kidney damage to slow the progression of the disease.

This may include:

Stage 2 CKD

With stage 2 chronic kidney disease, the damage to the kidneys is still mild, but the kidneys begin to function below their optimal capacity. Because symptoms usually don’t appear until stage 3, many people with stage 2 chronic kidney disease may not know they have kidney disease.

If symptoms appear, they may again involve foamy urine and/or an increased risk of urinary tract infections (UTIs), especially in females.

For stage 2 CKD, your doctor may recommend certain lifestyle changes in addition to managing your blood pressure and diabetes.

These may include:

Stage 3 CKD

Stage 3 of CKD occurs when your kidneys suffer enough damage to start producing symptoms. There are two sub-steps. Stage 3a is mild to moderate loss of kidney function. Stage 3b is moderate to severe loss of kidney function.

Increased kidney damage can lead to the loss of important nutrients like calcium and vitamin D, thereby affecting bone health. It can also cause a buildup of acid in your blood (metabolic acidosis) and a decrease in red blood cells (anemia).

Symptoms of stage 3a CKD may include:

• Urinating more or less often than usual
• Tiredness and tiredness
• Dry and/or itchy skin
• Nausea
• Loss of appetite
• Unintentional weight loss

In stage 3b, a person may additionally experience:

• Difficulty concentrating
• Muscle pain or cramps
• Shortness of breath
• Peripheral neuropathy (numbness or tingling sensation in the hands or feet)
• Peripheral edema (swelling of arms, legs, hands or feet)

With stage 3 CKD, additional interventions will likely be needed to control blood pressure and/or blood sugar while reducing the risk of disease complications.

These may include:

Stage 4 CKD

Stage 4 CKD means your kidneys are moderately to severely damaged, increasing your risk of complications such as anemia, high blood pressure, bone disease and metabolic acidosis.

The damage can also cause excessive potassium buildup (hyperkalemia) and phosphorus (hyperphosphatemia) in your blood, both of which can contribute to heart rhythm disorders and an increased risk of heart disease or stroke.

In addition to an increased risk of the symptoms listed above, stage 4 CKD can also cause:

• Persistent lower back pain
• Insomnia (difficulty sleeping)
• Breath that smells fishy or resembles ammonia or urine
• Hematuria (blood in the urine)

Additional aggressive treatments will be started to preserve your kidney function.

These include:

Treating stage 4 CKD can be difficult because many medications you take to manage high blood pressure and diabetes can suddenly put pressure on the kidneys and promote kidney damage.

Stage 5 CKD

Stage 5 is the most advanced stage of CKD, in which you have kidney failure. Also known as end-stage renal disease (ESRD), stage 5 CKD occurs when your kidneys are no longer functional enough to meet your body’s needs.

Stage 5 CKD is associated with uremiaa potentially dangerous condition in which waste builds up in your blood.

This can lead to potentially serious symptoms such as:

At this stage of the disease, the only treatment options are:

• Dialysiseither in the form of hemodialysis (using a device to filter your blood) or peritoneal dialysis (using the lining of your abdominal cavity to filter your blood)
• Kidney transplantationfrom either a living donor or a recently deceased donor

If left untreated, death will eventually occur. However, the time it takes to progress to death is variable.

Progression of the stages of the MRC

Chronic kidney disease usually progresses slowly over years. Despite this, many people do not realize they have the disease until it is in its advanced stages and the symptoms are severe enough to seek treatment. Of the 37 million adults living with chronic kidney disease in the United States, 1 in 9 people do not know they have the disease.

However, the progression of chronic kidney disease can be slowed or even stopped if the disease is diagnosed and treated early. With proper treatment and healthy lifestyle changes, many people with stage 1, 2, or 3 chronic kidney disease will never progress to stage 4 or 5.

This is demonstrated by a 2021 study in the Clinical Journal of the Kidney. It showed that among 88,766 people with CKD and diabetes, only 5 to 8.4 percent showed signs of progression over three years. Rapid progression of CKD – defined as progression through two stages of CKD within four years – is even less common, affecting only 2% of the study population.

Factors that may increase the risk of progression of chronic kidney disease include:

Being over 70 is also a factor, as aging is associated with a natural decline in kidney function and the progression of chronic diseases like diabetes.

Effect of chronic kidney disease on life expectancy

Chronic kidney disease is a leading cause of mortality (death) worldwide and one of the few noncommunicable diseases (those that are not transmitted to others through contact) for which annual deaths in the world world have increased over the past two decades.

Deaths from CKD in the United States are primarily due to heart disease,

CKD and heart disease often co-occur because they share many of the same risk factors, including high blood pressure, diabetes, and older age. Nearly a third of the 1,938,505 deaths reported in people with CKD in the United States between 1999 and 2020 were due to heart disease.

According to a 2023 review of studies involving 210,748 adults in the United States, CKD independently increases the risk of death from heart disease by more than three times.

Other common causes of death in people with CKD include:

Tracking and monitoring the stages of chronic kidney disease

If you are diagnosed with CKD, it is essential to regularly monitor your eGFR and other kidney function tests. Depending on your stage of chronic kidney disease, this may involve testing at least once a year. If and when CKD progresses, more frequent testing may be necessary.

Tests should involve the following blood and urine tests:

• EGFR
• Serum creatinine
• Urinary albumin
• Urinary albumin/creatinine ratio (UACR)

Routine tests may be recommended every four to six months if albumin levels are high and/or you have stage 3 or higher chronic kidney disease.

Some health experts recommend testing every two months for people with stage 4 chronic kidney disease and every month for those with stage 5 chronic kidney disease.

Summary

Chronic kidney disease has five stages. Stages 1 to 3 are often asymptomatic. Symptoms more often become apparent in stage 4. In stage 5, you are said to have end-stage renal disease (ESRD), in which you need either dialysis or a kidney transplant to survive.

The five stages of chronic kidney disease are determined by the results of an EGFR test. The test estimates how much blood your kidneys filter each minute.