Kidney disease

Kidney disease is used to describe any problems you may have with your kidneys. Your kidneys have a very important role in removing harmful waste products and unwanted fluid from your body, so long-term problems with your kidneys have an important effect on your health.

Kidney disease can be caused by high blood pressure, as the blood vessels in the kidneys or supplying the kidneys can become damaged by the extra pressure. This causes a reduced flow of blood through the kidneys and they respond to this by releasing hormones which raise your blood pressure higher still.

So high blood pressure and kidney disease interact with each other in a way that can have serious consequences for your health.

What are the symptoms of kidney disease?

Most people with kidney disease have no obvious signs or symptoms. This is because kidney damage tends to build up slowly and the kidneys are able to work well for a long time before the damage is enough to have visible effects. When the damage is severe enough, the signs are:

• fluid retention (for example ankle swelling)
• needing to go to the toilet more often (especially at night)
• erectile dysfunction  (also known as impotence)
• itchiness
• tiredness or weakness
• losing appetite
• feeling sick or vomiting.

How is kidney disease identified?

When you are first diagnosed with high blood pressure, your doctor may suggest tests to check that your kidneys are working properly: 

• Urine test: If there is protein or blood in your urine, this suggests that your kidneys may be damaged.
• Blood test: One specific blood test measures the amount of a particular protein called creatinine. It shows how well your kidneys are filtering waste products from your blood. The result is given as the glomerular filtration rate or GFR. The lower the GFR, the less well the kidneys are doing their job.
• Scans: Sometimes your doctor may wish to check the size and shape of your kidneys to make sure there are no problems. This is usually done using an X-ray or an ultrasound scan.

Can kidney disease be treated?

Once kidneys begin to lose their ability to work, this ability can not be regained. However, it is possible to avoid further damage to the kidneys.

Controlling your blood pressure is an important way to slow the progress of kidney disease. Many of the medicines used to treat high blood pressure can help the kidneys, but ACE inhibitors and angiotensin receptor blockers are thought to be particularly effective.

If you have diabetes as well as high blood pressure, it is extremely important to keep this controlled as well. Diabetes can cause serious damage to your kidneys if it is not treated properly.

Diet and kidney disease

Healthy eating will help to keep your blood pressure down and should also keep your blood sugar controlled if you have diabetes. This should help reduce the damage to your kidneys.

You may also be asked to try a special diet to reduce the amount of waste products your body produces. This will give your kidneys less work to do.

If you have kidney disease, it is very important that you do not use salt substitutes such as Lo-Salt. These products contain a lot of potassium and, if your kidneys are not working properly, potassium can build up, which can lead to heart problems.

How to lower your risk of kidney disease

You can keep your kidneys healthy by controlling your blood pressure, and if you have diabetes, by controlling your blood glucose.

If you smoke, have an unhealthy diet, or if you are overweight or not very active, you should think about changing to a more healthy lifestyle. This will help lower your blood pressure, and lower your risk of kidney disease as well.