Chronic kidney disease (CKD) is a long-term condition where the kidneys do not work as well as normal.

CKD does not usually cause any symptoms until it has reached an advanced stage. It is usually detected at earlier stages by blood and urine tests. The main symptoms of advanced kidney disease include:

• tiredness 
• swollen ankles, feet or hands (due to water retention) 
• shortness of breath 
• nausea  
• blood in the urine

The kidneys

The kidneys are two bean-shaped organs located on either side of the body, just underneath the ribcage. The main role of the kidneys is to filter out waste products from the blood before converting them into urine. The kidneys also:

• help maintain blood pressure 
• maintain the correct levels of chemicals in your body which, in turn, will help the heart and muscles function properly
• produce a type of vitamin D that keeps bones healthy 
• produce a substance called erythropoietin, which helps stimulate the production of red blood cells

How common is chronic kidney disease?

CKD is very common and is mainly associated with ageing. The older you get, the more likely you are to have some degree of kidney disease. It is estimated that about one in five men and one in four women between the ages of 65 and 74 has some degree of CKD.

The most common cause of CKD is damage caused by other chronic conditions, such as high blood pressure (hypertension) and diabetes.

CKD is more common in people of south Asian origin (those from India, Bangladesh, Sri Lanka and Pakistan) and black people than the general population. The reasons for this include higher rates of diabetes in south Asian people and higher rates of high blood pressure in African or Caribbean people. See the Live Well topics on Black health and South Asian health for more information.

Outlook

CKD is a potentially serious condition. People with CKD are known to have an increased risk of a stroke or heart attack because of the changes that occur to the circulation.

In some people, CKD may cause kidney failure, which is also known as established renal failure (ERF) or end-stage kidney disease. In this situation, the usual functions of the kidney stop working. In order to survive, people with ERF may need to have artificial kidney treatment, called dialysis.

However, if the condition is diagnosed at an early stage, further damage to the kidneys can be prevented with a combination of lifestyle changes and medication. These changes can also reduce your risk of a stroke or heart attack. It is, therefore, very important to help yourself as much as you can.

Want to know more?

• NKF: About the kidneys.
• Kidney Research UK: Chronic kidney disease (CKD) (PDF, 300Kb).
• British Association for Paediatric Nephrology: Patient advice leaflets.