What Is Chronic Kidney Disease? Symptoms, Causes, and Treatment

The Centers for Disease Control and Prevention (CDC) estimated that 37 million Americans were living with chronic kidney disease (CKD) in 2021. When you have this medical condition, it means your kidneys—the bean-shaped organs located on either side of your spine—are damaged and can't filter your blood the way they should. While it can be devastating to get this diagnosis, most people with the disease are still able to live healthy and productive lives.

"When people learn that they have chronic kidney disease, they automatically assume they'll need dialysis, but with proper treatment, they can manage this disease well for years," said David Goldfarb, MD, clinical chief of nephrology at NYU Langone Health in New York City.

If you're living with chronic kidney disease, here's what experts want you to know.

What Is the Function of Your Kidneys?

To understand what causes chronic kidney disease, it helps to have a refresher on normal kidney function. Think of them as your own personal body filters. Your kidneys work to clean your blood, removing things like waste and excess water. Blood enters each of your kidneys through your renal arteries. From there, it's put through millions of tiny blood filters known as nephrons to be cleaned before waste material is sent to your bladder as urine.

Normally, healthy kidneys work like a well-oiled machine, filtering about 200 quarts of fluid every 24 hours. (Roughly two quarts of that leave your body in your urine; the remaining 198 quarts stay in the body). But for them to work properly, the arteries leading to your kidney need to be healthy, as do the nephrons. If they're not, you can run into trouble.

What Causes Chronic Kidney Disease (CKD)?

Chronic kidney disease can be due to a genetic mutation, another disease, or repeated kidney infections. The following illnesses cause some kind of damage to the kidney, causing kidney disease.

Diabetes

Diabetes causes your blood sugar levels to be high. This can injure all the small blood vessels in your body, including those in your kidneys. As a result, your kidneys can't filter your blood properly. About 30% of people with type 1 diabetes and up to 40% of those with type 2 diabetes will ultimately experience kidney failure.

High Blood Pressure

When you have hypertension, the pressure of your blood against the walls of your blood vessels increases, explained Dr. David Goldfarb. This damages the blood vessels, including the ones that bring blood to and from your kidneys.

Glomerulonephritis

Glomerulonephritis is a group of diseases that damage the blood-filtering nephrons in your kidneys. As a result, they can't filter your blood properly. Glomerulonephritis can be caused by certain illnesses, like lupus; or infection, such as strep throat.

Autoimmune Diseases

Autoimmune disorders can cause your immune system to attack any organ in your body, including your kidneys.

Polycystic Kidney Disease

This is a disorder where cysts, or fluid-filled sacs, develop in your kidneys. This makes it hard for it to filter waste properly. The kidneys may become enlarged, causing kidney failure. Polycystic kidney disease is caused by a genetic mutation.

Recurrent Kidney Infections

In rare cases, repeated kidney infections can cause kidney scarring, which can lead to chronic kidney disease. These are typically caused by bacteria or viruses.

Symptoms

About 90% of people with CKD don't realize that they have it, according to the NKF. "Most patients don't develop signs of the disease until it's fairly advanced," said Staci Leisman, MD, a kidney specialist at Mount Sinai Hospital in New York City. That being said, there may be some symptoms that start earlier, Dr. Staci Leisman noted.

Swollen Ankles and Feet

As your kidney function goes down, your body is less able to filter out salt, explained Dr. Staci Leisman. It can build up, causing swelling in your feet and ankles.

Anemia

When you have kidney disease, your kidneys have trouble producing erythropoietin (EPO), a hormone that tells your body to make red blood cells. As a result, your red blood cell count drops. Your healthcare provider may pick this up on a routine lab test, or you may notice that you feel weak, tired, dizzy, short of breath, or have difficulty concentrating. These are all symptoms of anemia in people with CKD.

A Metallic Taste in Your Mouth

When you have kidney disease, waste products build up in your body, including one known as urea, said Dr. Staci Leisman, which can affect your taste buds.

Peeing More at Night

When your kidney filters are damaged, you can feel the urge to urinate more often. This can be especially noticeable at night when you lie down because the extra fluid around your ankles, feet, and legs can now flow up to your kidneys, explained Dr. Staci Leisman.

Later Signs

According to the US National Library of Medicine, as the disease progresses, you may experience any of the following:

• Headache
• Unexpected weight loss
• Nausea
• Decreased appetite
• Dry and itchy skin
• Trouble concentrating
• Difficulty sleeping
• Blood or "foamy" urine

By the time these symptoms hit, "you've really missed the window to treat your chronic kidney disease," said Dr. Staci Leisman. As a result, your kidneys have become so damaged they're no longer able to filter out most toxins, leading them to build up in your bloodstream.

Diagnosis

There are two main tests healthcare providers use to diagnose CKD, said Dr. David Goldfarb. The first is a blood test called the glomerular filtration rate (GFR). This checks how well your kidneys filter blood. A GFR of at least 60 is considered normal, while less than that indicates kidney disease. A number of 15 or less means kidney failure.

The second test is a urine test called urine albumin-creatinine ratio (uACR). This checks for albumin, a protein that can show up in your urine if your kidneys are damaged. The normal amount of albumin is anything less than 30 mg/g. A number above this may indicate kidney disease.

If you have kidney disease, your healthcare provider will also run these tests periodically to make sure your current treatment is working. This means a GFR should stay the same or rise, and a urine albumin level will go down.

Treatment

If you're diagnosed with CKD, you'll need to see a nephrologist (kidney doctor). The earlier you are diagnosed and treated, the less chance you have to develop complications from your CKD. There are five stages of kidney disease­­-stage 5 is when you would need dialysis or a transplant to live. For people in earlier stages (1-4) there are things you can do to stop kidney disease from worsening. There's no cure for CKD, but most people are able to manage it with the following steps.

Control Your Blood Pressure

"This is probably the most important part of treatment for people with CKD," said Dr. Daniel Goldfarb. Up to 85% of people with CKD have high blood pressure, but if you get it under control, you can slow its progression, Dr. Daniel Goldfarb noted. Two classes of blood pressure medications—angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARB) help to lower blood pressure and protein levels in urine.

Monitor Your Diet

People with CKD should have no more than 2,300 milligrams of salt a day, according to the NIDDK. "When your kidneys are damaged, they can't filter out sodium very well, which means it can stay in your body and raise your blood pressure," said Dr. Staci Leisman.

You should also go easy on the protein, as it's hard on your kidneys. Additionally, people with CKD develop high potassium and/or high phosphate levels, so they need to scale back on certain foods, according to the NIDDK. It's a good idea to work with a dietitian to come up with a doable meal plan.

Keep Tabs on Your Cholesterol and Blood Sugars

These are both often elevated in people with CKD, said Dr. David Goldfarb. To treat high cholesterol and diabetes, you may need to take medication.

Be Careful With Over-the-Counter Medications

If you have CKD, you want to avoid taking any nonsteroidal anti-inflammatory drugs (NSAIDs) to treat pain, fever, or cold symptoms. NSAIDs can damage your kidneys even further. It's a good idea to always check with your healthcare provider before you take any new over-the-counter medication, dietary supplement, or herbal product.

Increase Your Exercise

Exercising and staying active is a great way to help your kidneys. A review published in 2019 found that staying active boosted the GFR rate and also helped keep other medical conditions like high blood pressure under control.

Dialysis and Kidney Transplant

With these steps, you may be able to keep your kidneys functioning healthfully for years. But some people find that despite their efforts, they have developed kidney failure. This is when about 90% of your kidney function is gone. If this happens, there are two main options: dialysis, a treatment that filters your blood using a machine, or a kidney transplant. According to the NIDDK, only two in every 1,000 people with CKD needed a kidney transplant or dialysis in 2020.

"In general, we're more concerned about someone with chronic kidney disease having a heart attack or stroke because of other cardiovascular risk factors than we are about them eventually needing dialysis," said Dr. David Goldfarb. That's why it's so important to get those other risk factors under control too.

Prevent Chronic Kidney Disease (CKD)

While there's no magic way to prevent CKD, you can help lower your risk by following a healthy lifestyle, said Dr. David Goldfarb. A few pointers:

Eat a Healthy Diet

A 2019 review of 18 studies published in the Clinical Journal of the American Society of Nephrology found that a healthy diet rich in fruits, veggies, legumes, nuts, whole grains, fish, and low-fat dairy was associated with a lower incidence of CKD.

Stay Active

The more exercise you get, the lower your risk of kidney disease, according to a 2020 study published in the British Journal of Sports Medicine. The study found that those who were the most physically active were less likely to develop kidney disease over that time period than those who were more sedentary.

Don't Smoke or Drink Too Often

Smoking slows blood flow to all of your major organs, including your kidneys, according to the NKF. Additionally, excessive alcohol consumption increases your blood pressure and the risk for CKD, according to the NKF. An occasional drink is fine, but keep it in moderation—both regular heavy drinking and binge drinking raises the chances of kidney damage.

A Quick Summary

Chronic kidney disease can be managed for years with the proper treatment. It's important to monitor your diet, stay active, and stay on top of the treatment for any other illnesses you may also be dealing with (like diabetes and high blood pressure). Since every kidney disease is different, consult your healthcare provider for the proper course of treatment to manage your CKD.