Anemia in chronic kidney disease: How does chronic kidney disease (CKD) cause anemia, Symptoms, Causes, Diagnosis and Treatment


Anemia is a common side effect of kidney disease when the kidneys are unable to help your body produce the required amount of red blood cells.

August 23, 2018

Anemia in chronic kidney disease: How does chronic kidney disease (CKD) cause anemia, Symptoms, Causes, Diagnosis and Treatment

Anemia is a common side effect of kidney disease when the kidneys are unable to help your body produce the required amount of red blood cells.

The oxygen that we breathe in passes through our lungs and into the red blood cells, that carry oxygen through your bloodstream, giving you energy and helping your muscles, bones, and organs work properly. There are not enough red blood cells to carry this oxygen around the body in anemia. Anemia can make you feel weak and tired because you are not getting enough energy.

How does chronic kidney disease (CKD) cause anemia?

Anemia is very common in people with CKD although anybody can develop it. Anemia can occur in the early stages of CKD, and it usually gets worse as the disease progress. If your kidneys are not working as well as they should, you are more likely to get anemia. Anemia in CKD is more common if you have diabetes, heart problem, high blood pressure. It is also common if you are older than 75 years.

Symptoms of anemia:

Anemia can happen with or without symptoms. As many of the symptoms of anemia can also be caused by other problems, you should get a confirm diagnosis if you experience the below symptoms:

Dizziness, loss of concentration:

Feeling dizzy or having difficulty concentrating may be a sign that your brain is not getting enough oxygen due to lack of red blood cells.

Pale skin:

Paleness of skin can be due to reduced blood flow or a lower number of red blood cells.

Chest pain:

As the heart has to work harder to provide blood to your body in anemia in CKD, it can increase your risk of heart problems. Consult your doctor if you experience an unusually fast heart rate or are worried about your heart health.

Shortness of breath:

Your blood may not have enough red blood cells to deliver oxygen to your muscles, there by increasing your breathing rate to bring more oxygen into your body.

Fatigue or weakness:   

Easy fatigue, loss of energy, and reduced physical capacity due to lack of oxygen in blood and muscles.

Cold intolerance:

Sensitivity to the cold may indicate there is not enough oxygen being delivered in the blood to your body.

Causes of anemia in CKD:

There are two main causes of anemia in CKD. Anemia caused by having too little EPO or too little iron in your body are the most common in people with CKD.

CKD and erythropoietin:

The cells in your body live for a certain amount of time and then die. Red blood cells live for about 115 days. Your body is always working to make new cells to replace the ones that have died. Your kidneys help your body make red blood cells.
Healthy kidneys make a hormone called erythropoietin (EPO), which sends a signal to the body to make more red blood cells. If your kidneys are not working properly as they should, they becomes unable to produce enough EPO. Without enough EPO, your body doesn't get signal to make enough red blood cells. This results in fewer red blood cells available for carrying oxygen through your body.

CKD and iron:

Iron is a mineral used by our body to make red blood cells. Iron is found in many foods, such as meats and leafy greens. Iron deficiency is the most common cause of anemia in people with CKD. It can be caused by not getting enough iron in your diet or by losing blood, either through blood tests or during dialysis.
You can develop anemia if you are not getting enough of iron from your food. Causes of iron deficiency could be:

  • Not eating enough foods that are rich in iron
  • Iron from your food is not being absorbed properly into your bloodstream
  • Frequent blood donation or testing may increase demand for iron
  • Blood loss from dialysis

Diagnosis of Anemia when you have CKD:

The only way to diagnose anemia in CKD is to have a blood test. You need to do blood tests often when you have CKD. These tests are used to check not only your kidney function, but also for signs of any other problems, such as the number of red blood cells and how much iron you have in your body. The test for anemia is a simple blood test to check for the amount of hemoglobin in your blood. Hemoglobin is a part of your red blood cells. Knowing the hemoglobin level it makes easier to find out if you are anemic.
You can also do a complete blood test or CBC which will provide you a detail information. Changes in skin color or feeling unusually tired are the symptoms to be noticed.

Treatment of Anemia when you have CKD:

Depending on the cause of your anemia, one of the following treatments may be recommended by your doctor:

Erythropoiesis-stimulating agents (ESAs):

ESAs are medicines that work by sending a signal to the your body to make more red blood cells.

Iron supplements:

Iron supplements as pills or as a shot may be given to you. You may be given an iron supplement during your dialysis treatment if you are on dialysis.

Red blood cell transfusion:

A red blood cell transfusion is a procedure to increase the number of red blood cells in your body by giving you red blood cells through an IV from a donor. This can temporarily improve your anemia symptoms.
Getting early treatment for your anemia can help slow the progress of your CKD.