The kidneys are two small fist-sized, bean-shaped organs situated on the lower back of the abdomen. Small they may be, but they do an enormous job. In fact, one functioning kidney is essential for life – a really good reason then for celebrating what is known as World Kidney Day; this year on 11 March.
If the lungs are our air-conditioning unit, then the kidneys are our body’s washing machine and waste disposal system. They’re also a superbly effective filter system with about 200 litres of blood passing through 2 million tiny filters every day; resulting in the removal of about 2 litres of waste products and unneeded water.
As well as enabling us to excrete certain unwanted and toxic substances, the kidneys produce hormones and regulate water levels and blood pressure.
Of course, properly regulated blood pressure is critical for good health. While there are no firm and fast rules about what constitutes a normal blood pressure reading – blood pressure varies from person to person and with individuals from time to time – a confirmed reading of greater than 140/90 is considered sufficiently high to require treatment.
There is a close relationship between high blood pressure and kidney disease: high blood pressure can cause kidney damage and kidney damage can cause high blood pressure.
The kidneys produce a hormone called renin which helps control blood pressure. When the kidneys are not functioning effectively, there is often an increase in the release of renin and a subsequent rise in blood pressure. Likewise, if high blood pressure is left unchecked, it can cause the walls of blood vessels in the kidneys to become, thickened. The blood vessels therefore become narrow causing reduced kidney function and ultimately kidney failure.
Uncontrolled blood glucose levels (diabetes) is another major risk factor for long-term or so-called chronic kidney disease (CKD). About half of all people with diabetes develop kidney damage; so it’s important for people with diabetes to have regular kidney function tests.
With diabetes, all the small blood vessels in the body are damaged; and those in the kidneys are especially vulnerable. The blood cleaning activity of the kidneys does not operate effectively; the body retains more salt and eater than it should, leading to swelling of the ankles and weight gain.
Diabetes may also cause damage to the nerves in the body. This can cause difficulty in emptying the bladder and further injury to the kidneys. Kidney failure is one of the most serious complications of diabetes; and kidney failure cause or contributes to about 10% of all deaths in Australia.
Being overweight or obese are in themselves risk factors for kidney disease. As well as increasing the likelihood of both blood pressure and diabetes (and therefore increasing the risk of CKD), as we get bigger and more overweight, the kidneys have to cope with a greater workload.
Being overweight is a very visible characteristic, but having high blood pressure and diabetes can often go unnoticed until the CKD is well established and difficult to treat. So a regular visit to the doctor is essential. The kidney health check involves a blood pressure test, a urine test for protein and blood test for a substance called creatinine.
Prevention strategies (and often initial treatment as well) involves dietary and lifestyle changes – losing weighty, cutting down on alcohol intake, exercising regularly, consuming less salt and stopping smoking. If medication is necessary it may involve life-long treatment.
This year the theme for World Kidney Day is ”Protect your kidneys – control diabetes”. You can get more information about diabetes and high blood pressure and their relationship to kidney disease from pharmacies throughout Australia providing Self Care health information. For the nearest location phone the Pharmaceutical Society on 1300 369 722 or check the website www.psa.org.au and click on Self Care Pharmacy Finder.
