Chronic Kidney Disease (CKD)

Overview

What is chronic kidney disease (CKD)?

Chronic kidney disease occurs when your kidneys are damaged and no longer work as well as they should. Normal, healthy kidneys remove waste from the blood. The waste then leaves your body in your urine. The kidneys also help control blood pressure and make red blood cells. If you have chronic kidney disease, your kidneys cannot remove waste from the blood as well as they should. Almost 20 million people in the United States have this disease.

Symptoms

What are the symptoms of CKD?

Most people don’t have any symptoms early in the disease. Once the disease progresses, the symptoms can include the following:

  • Feeling tired
  • Feeling weak
  • Loss of appetite
  • Not sleeping
  • Not thinking clearly
  • Swelling of the feet and ankles

Causes & Risk Factors

What causes CKD?

The most common causes of CKD are high blood pressure, diabetes and heart disease. Chronic kidney disease can also be caused by infections or urinary blockages.

Am I at risk for CKD?

You may be at risk if someone in your family has CKD or if you have diabetes or if you have high blood pressure. Talk to your doctor about your risk factors. It is important to diagnose CKD early.

Diagnosis & Tests

How can my doctor tell if I have CKD?

There are three simple tests that your doctor might do if he or she suspects you might have chronic kidney disease:

Screening for chronic kidney disease in all adults is not currently recommended. If you have a condition that puts you at very high risk for chronic kidney disease, such as diabetes or high blood pressure, talk to your doctor about whether you should be tested.

  • Blood pressure test
  • Urine albumin (a test to see how much protein is in the urine)
  • Serum creatinine (a test to see how much creatinine, a waste product, is in the blood)

Treatment

I have CKD. What can I do to prevent or slow down problems?

Your doctor will talk to you about treating the problems that damaged the kidneys.

If you have high blood pressure, it is important to lower your blood pressure. Medicines called ACE inhibitors and angiotensin-II receptor blockers can be helpful. These medicines lower blood pressure and may help keep your kidney disease from getting worse. Exercise and a healthy diet can also help to lower your blood pressure.

If you have diabetes, your doctor will tell you what to do to keep your blood sugar level normal. You will probably need to change your diet, get more exercise and/or take medicine.

If you smoke, you must quit. Smoking damages the kidneys. It also raises blood pressure and interferes with medicines used to treat high blood pressure.

Your doctor may also want you to eat less protein. Too much protein can make the kidneys work too hard.

You will need to have regular checkups so your doctor can check how your kidneys are working and treat problems caused by CKD.

How else is CKD treated?

Chronic kidney disease can cause other problems. Talk with your doctor about how you can treat these other problems. He or she may have you take medicine to treat:

If you have chronic kidney disease, you may lose your appetite. A nutritionist can help you plan a diet that will keep you strong.

  • High triglyceride (say: “try-gliss-er-eyed”) and cholesterol levels. Triglycerides are a type of fat. Triglyceride levels often are higher in people who have kidney disease.
  • Anemia. Anemia occurs when your blood doesn’t have enough hemoglobin (a protein that carries oxygen from the lungs to the rest of the body). Symptoms of anemia include feeling tired and weak.
  • Weak bones. CKD can also change the way your body uses minerals such as calcium and phosphorus that are used to make bone. Your doctor may have you avoid certain foods to help your body use these minerals better.

Chronic Kidney Disease and Nutrition

I have chronic kidney disease. Why is my nutrition so important?

If you have chronic kidney disease, your kidneys are not able to work as well as they should to remove waste from your blood. This allows waste to build up, which can lead to additional health problems and put extra stress on your kidneys.Some of the waste in your blood comes from foods you eat, so following a special diet can help avoid a buildup. Reducing the stress on your kidneys can slow the progress of kidney disease.

I’m on dialysis. Do I still need to be concerned about nutrition?

Yes, you still need to watch what you eat. Dialysis can filter your blood very effectively, but it can’t remove all of the waste your body makes when it processes nutrients. You are at increased risk of waste levels rising between your dialysis sessions.

What foods add to the buildup up of waste in my blood?

Some of the waste that can build up in your blood comes from nutrients in the food you eat. Your body actually needs most of these nutrients for its day-to-day functions. But when your kidneys aren’t working well, certain nutrients can become a problem. Phosphorous. Phosphorous is a mineral that can help keep bones healthy and strong. However, even in early stages of chronic kidney disease, the level of phosphorous in your blood can become too high. A high level of phosphorous can cause itchy skin. It can also cause your bones to lose calcium. If this happens, your bones will get weaker and more brittle. You also have a greater risk of developing osteoporosis.Foods that are high in phosphorous include the following:

If your phosphorous level is too high even after you change your diet, your doctor may prescribe a medicine to lower it. Calcium. You need calcium to build strong bones. Unfortunately, foods that contain calcium often also contain phosphorous. If you have chronic kidney disease, you may need to take calcium supplements that are phosphorous-free. Your doctor may also prescribe a special type of vitamin D to help your body absorb calcium. Protein. You need protein to build and maintain healthy muscles, bones, skin and blood. Protein also helps your body fight infection and heal wounds. When protein breaks down, it turns into waste products. Kidneys damaged by disease aren’t able to stop this waste from building up in the blood.Potassium. Potassium is a mineral that helps your muscles and heart work properly. It is found in foods such as bananas, potatoes, tomatoes, avocados and melons. Having too much or too little potassium in your blood can cause serious problems. You may need to watch your potassium intake. Your doctor will determine whether you need to change the amount of potassium in your diet. This will depend on the stage of your kidney disease and whether you are taking medicine to help lower your potassium level. Sodium. If you take in too much sodium (salt), you may retain fluid. This extra fluid can raise your blood pressure, putting stress on your heart and kidneys.Check food labels for sodium. Packaged and processed foods are often high in sodium. You may know that foods such as soy sauce, processed meats, crackers and potato chips contain a lot of sodium. But you may not realize how much sodium is in foods like bread, canned vegetables, soups and cheese. Look for sodium-free or low-sodium foods.Don’t add salt to your food. Try different seasonings, such as lemon juice, hot pepper sauce and salt-free seasonings. Avoid salt substitutes. They often contain high levels of potassium. Fluids. If you have trouble getting rid of fluid from your body, you need to be careful about how much fluid you drink. Too much fluid can put additional strain on your kidneys. Calories. You need to take in the right amount of calories to maintain a healthy weight and support your body’s functions. This can be challenging for people who have chronic kidney disease. Limiting the amount of protein, dairy, salt and certain nutrients in your diet reduces your food choices. Foods you used to eat may no longer be healthy options. Also, your appetite may be affected by chronic kidney disease. Even if it’s fine to eat certain foods you used to enjoy, they may not have the same appeal.Your family doctor can help you make a diet plan that supports your kidney health. This is important because your diet may need to change as your kidney disease and the medicines you take change. Your doctor may recommend that you work with a registered dietitian to be sure you get the right amount of calories each day and avoid problems.To increase your calorie intake, your doctor or dietitian may suggest adding simple carbohydrates, such as those found in hard candy, honey and jelly. Fats can be a good source of calories, but saturated fats increase your risk of cardiovascular disease. Instead, choose monounsaturated or polyunsaturated fats, such as olive oil or canola oil. These “good” fats are better for your cardiovascular health.

  • Dairy products, such as milk, cheese, yogurt and ice cream
  • Dried beans and peas, such as kidney beans, split peas and lentils
  • Nuts and peanut butter
  • Drinks like beer, cola and hot cocoa

How can I track how my diet is affecting my kidneys?

A number of tests are available to track how well your kidneys are working and whether your diet is reducing the stress on your kidneys.To measure how well your kidneys are filtering waste from your blood, your doctor may estimate your glomerular filtration rate (eGFR). This test evaluates the amount of creatinine (a kind of waste) in your blood. A declining eGFR indicates that your kidney function is getting worse. Other changes in your diet and/or medication may be necessary.A simple dipstick urine test can reveal whether your kidneys are losing function. This test measures albumin and other protein wastes that build up when the kidneys aren’t working well.The serum albumin test is a blood test that shows whether you are taking in enough protein and calories. If you’re not, you may be at risk of infections and you may not feel well overall.The normalized protein nitrogen appearance (nPNA) test measures your protein balance to determine whether you are getting enough protein. This test involves a blood and urine sample.The blood urea nitrogen (BUN) test measures the level of urea in the blood. Urea is one of the wastes left over when your body breaks down protein. A high BUN level may indicate that you are taking in too much protein.Your doctor may also do a physical exam and ask some questions to identify any problems with your diet. He or she will want to know about any changes in your weight or your body fat and muscle. Your doctor may also ask about the amount of food you eat, as well as your activity and energy levels.

This content was developed with general underwriting support from Nature Made®.

Complications

What happens when CKD gets worse?

Even with the right treatments, CKD can get worse over time. Your kidneys could stop working. This is called kidney failure. If this happens, waste builds up in your body and acts like a poison. This poisoning can cause vomiting, weakness, confusion and coma.

If your kidneys have failed, your doctor will send you for dialysis (say: “die-al-uh-sis”). During dialysis, a special machine is used to filter the blood and remove waste that builds up. One kind of dialysis has to be done in a clinic. For another kind of dialysis, the machine is so small it can be strapped to your body while you go about your daily activities. If you need dialysis, your doctor will talk with you about which kind of dialysis machine you can use.

Questions to Ask Your Doctor

  • What treatment is best for me?
  • What is causing my kidney disease?
  • Should I follow a special diet?
  • What exercise is best for me?
  • Do I need to lose weight?
  • Will I need dialysis?
  • Can chronic kidney disease be cured?
  • Will I continue to get worse?
  • Are there any medicines I should take?
  • Will I need a kidney transplant?

Citations