When you have chronic kidney disease (CKD), your kidneys slowly stop working properly. The damage is lasting and can get worse over time, leading to different stages of CKD.
Anyone can get CKD, but some people are more likely to get it. It's associated with getting older and is more common among people of South Asian, Black, and Hispanic descent. When younger people get CKD, the disease tends to worsen, whereas people older than 65 years tend to have stable disease.
There is no cure for CKD, but early diagnosis and treatment can help stop the disease from getting worse. Many people live long and normal lives with CKD, but it's important to see your doctor regularly to manage your condition.
What Are the Stages of CKD?
Because it's a progressive disease, meaning it can get worse, doctors classify CKD into stages from 1 to 5 to show how serious it is at a given point.
In stages 1-3, considered to be early-stage CKD, your kidneys are still working normally or close to it. In stages 4 and 5, considered to be late-stage CKD, your kidneys are working poorly or not at all.
CKD Staging
CKD staging is based on your kidneys' filtering speed. These organs keep a healthy balance between water, salts, and minerals like sodium, calcium, and potassium in your body by taking extra fluid and waste out of your blood.
The filtering structures inside your kidneys are called nephrons. Each nephron has a glomerulus, which filters your blood, and a tubule, which removes the waste and returns what you need back to your blood.
How quickly your blood passes through these structures is called called the glomerular filtration rate (GFR). It's expressed as a number of milliliters per minute. If your kidneys are damaged, this GFR will be lower.
It's a hard process to measure the GFR exactly, so it's usually estimated. You'll have a test that measures the level of a waste product, called creatinine, in your blood. That number goes into an equation, along with your age, sex, and body size, to calculate your estimated GFR (eGFR).
Another test that goes into CKD staging measures the amount of protein in your pee. The urine albumin-creatinine ratio can show that you have damage to your kidneys even if your filtering rate is normal.
CKD Stages
Each stage of CKD is made up of a range of filtering speeds:
Stage 1. Mild kidney damage with an eGFR above 90 milliliters or greater per minute
Stage 2. Mild damage with 60-89 milliliters per minute
Stage 3a. Moderate damage with 45-59 milliliters per minute (This is the most common stage.)
Stage 3b. Moderate damage with 30-44 milliliters per minute
Stage 4. Severe damage with 15-29 milliliters per minute
Stage 5.Kidney failure with less than 15 milliliters per minute, a level at which the kidneys are no longer working
Stage 5 CKD is also called end-stage renal disease. At this stage, you will need dialysis or a kidney transplant. Not everyone has CKD that worsens, though.
CKD Symptoms by Stage
The symptoms you have with CKD are different depending on the stage.
Stages 1 and 2
Early stages of CKD usually don't cause any symptoms because your kidneys are still filtering well. Early CKD is often only found because routine tests showed protein or blood in your urine, or you were diagnosed with high blood pressure. However, you might also have:
- Swollen hands or feet
- Urinary tract infections
- Foamy pee
Your doctor might also discover kidney damage on an ultrasound, a CT scan, or an MRI you had for another reason.
Stages 3a and 3b
In these stages, your body may still be able to adjust to the lower filtration rate. But this is when most people start having symptoms. They may include:
- Swollen ankles and feet
- Weight loss
- Poor appetite
- Muscle cramps
- Tiredness
- Shortness of breath
- Trouble sleeping
- Itchy skin
- Peeing more often, especially at night
- Foamy or dark-colored pee
Stages 4 and 5
In the later stages of CKD, waste products build up in your blood and can start causing serious complications. In addition to the symptoms listed for stages 3a and 3b, you may have:
- Trouble concentrating
- Headaches
- Lower back pain
- Numbness in your arms or legs
- Nausea and/or vomiting
- Peeing less often or not at all
- Bad breath
- Unusual skin color
What Is the Treatment for CKD?
There is no cure for CKD, but treatment can relieve your symptoms and stop the disease from getting worse. In the early stages, that usually involves making lifestyle changes and managing any underlying conditions. Treatment in later stages may include medication to stop kidney damage or procedures to make up for the loss of kidney function.
Stages 1 and 2
While damage to your kidneys is still mild, the main goal of treatment is to keep it from getting worse. Your doctor may recommend:
- Stopping smoking
- Eating a low-fat, low-salt diet
- Getting regular exercise
- Losing weight and keeping a healthy weight
- Controlling your blood sugar, if you have diabetes
- Lowering high blood pressure
You may need to take medication in these stages to manage your blood sugar, blood pressure, or cholesterol.
Stages 3a and 3b
In these stages, you are losing more of your kidney function. While healthy lifestyle choices are still important, you may also need to take medication to treat CKD symptoms or slow their progression. These include:
- Blood pressure medications. These may slow damage to your kidneys even if you don't have high blood pressure.
- Cholesterol-lowering medications
- Diabetes medications. Drugs called SGLT2 inhibitors can benefit your kidneys even if you don't have diabetes.
- Diuretics. These help your kidneys remove more salt and fluid from your body.
- Medicines or supplements can keep your bones strong and prevent anemia.
In these stages, your doctor may also recommend drugs to help keep the correct balance of minerals in your body.
Stages 4 and 5
As your kidneys get closer to failing, medicines will no longer be enough to keep you healthy. In the later stages of CKD, treatment options include:
- Dialysis, a treatment that does some of the filtration work for your kidneys
- Transplant after kidney failure, a surgery to replace your kidneys with donated organs
Takeaways
The stages of CKD indicate how well your kidneys are working to filter waste and extra fluid out of your blood. The stages are based on a measure called the GFR — your kidneys' filtering speed. In early stages, the rate is higher, and your kidney function is normal or close to it. In later stages, the speed is lower, and your kidneys are working poorly or not at all.
Stages of CKD FAQs
How fast does kidney disease progress?
In general, kidney disease progresses slowly. But because it often doesn't cause symptoms in the early stages, it can be hard to know exactly when it starts. How fast it progresses depends on your treatment and how well you can control underlying conditions that make it worse.
How long can you live with end-stage kidney disease?
Once you're diagnosed with stage 5 CKD, also called end-stage kidney disease, your life expectancy depends on your treatment. With dialysis, people live an average of 5-10 years. With a transplant, people live an average of 10-20 years. If you have neither of these, you are unlikely to live more than a few weeks.
Can you reverse kidney disease?
No. Damage to your kidneys, whether from diabetes, high blood pressure, or other causes, is permanent. But with treatment and lifestyle changes, you can slow it down or keep it from getting worse.