World Kidney Day Article

by: Dr. Murtaza F Dhrolia - Consultant Nephrologist

The Kidney Centre Post Graduate Training institute

It has always been debatable to define the word "elderly" as aging is an evolutionary process that progresses at different rates in different people. To draw a line, most consider the age of 65 as a chronological cut-off beyond which a person is considered a senior citizen or elderly. Aging is a normal physiological process characterized by:

A) Rate of deterioration or degeneration that is controlled by an intrinsic biological clock.

B) Aging is universal.

c) Aging is irreversible.

Aging proceeds at different rates, not only in different people but also in different organs and tissues of the same person. Thus the function of the kidneys and lungs declines faster than the function of the brain and heart.

Kidneys age, as you age, rather faster than other organs. The kidneys are part of the urinary system, which also includes the ureters, bladder, and urethra. The two kidneys lie to the sides of the upper part of the tummy (abdomen) on either side of the spine. Each kidney is about the size of a large orange, but is bean-shaped.

World Kidney Day is celebrated on 13th March every year. It aims to raise awareness of the importance of our kidneys to our overall health and to reduce the frequency and impact of kidney disease and its associated health problems worldwide.

A large artery - the renal artery - takes blood to each kidney. The artery divides into many tiny blood vessels (capillaries) throughout the kidney. In the outer part of the kidneys, tiny blood vessels cluster together to form structures called glomeruli.

Each glomerulus is like a filter. The structure of the glomerulus allows waste products and some water and salt to pass from the blood into a tiny channel called a tubule. The liquid that remains at the end of each tubule is called urine.

The urine then passes down a tube called a ureter which goes from each kidney to the bladder. Urine is stored in the bladder until it is passed out, when we go to the toilet.

The main functions of the kidneys are to:

• Filter out waste products from the bloodstream, to be passed out in the urine.

• Help control blood pressure - partly by the amount of water passed out of the body as urine and partly by making hormones, which are involved in blood pressure control.

• Make a hormone called erythropoietin, which stimulates the bone marrow to make red blood cells. This is needed to prevent anemia.

• Helps in activation of inert vitamin D to maintain the health of bones.

• Help keep various salts and chemicals in the blood at the right level.

There is overall reduction in renal functions with aging, but with a marked variation among subjects of the same age. Kidney function of an elderly person may appear grossly abnormal in comparison to that of a young adult, however most of these changes are a normal part of aging and should be looked upon as part of physiology rather than pathology.

As the kidneys age, these structural and functional events occur:

• Overall amount of kidney tissue decreases.

• Number of filtering units (nephrons= glomerulus + tubule) decreases

• Blood vessels supplying to the kidneys can become hardened. This causes the kidneys to filter blood more slowly.

• Amount of plasma filtering through glomerulus decreases i.e. glomerular filtration rate (GFR) decreases.

• Concentrating and diluting capacity diminishes

• Diminished capacity to excrete a sodium load and/or to conserve sodium during a low-sodium intake.

• Decreased ability to conserve potassium

As a consequence of above mentioned changes; illness, medications, and other conditions, can affect the ability of the aged kidneys to function properly.

Kidney disease is called a ‘silent disease’ as there are often no warning signs. People may lose up to 90 per cent of their kidney function before getting any symptoms. The first signs of kidney disease may be general and can include:

• High blood pressure

• Changes in the amount and number of times urine is passed (for example, at night)

• Blood in the urine

• Puffiness

• Pain in the kidney area

• Tiredness

• Loss of appetite

• Difficulty sleeping

• Headaches

• Lack of concentration

• Itching

• Shortness of breath

• Nausea and vomiting

• Bad breath and a metallic taste in the mouth.

Contact your health care provider if you have any of the above symptoms.

Because renal function decreases with age, it is important to consider following things to keep your kidneys healthy, including:

• If you have diabetes, make sure that your blood sugar control is excellent. Follow your doctor’s advice about insulin injections, medicines, diet, physical activity and monitoring your blood sugar.

• Control high blood pressure. Have your blood pressure checked regularly.

• If you have one of the risk factors for kidney disease, have a Kidney Health Check (blood test, urine test and blood pressure check) at least every two years (every year if you have diabetes or high blood pressure).

• Treat urinary tract infections immediately.

• Control blood cholesterol levels with diet and medications if necessary.

• Choose foods that are low in sugar, fat and salt, but high in fiber. Stick to moderate serving sizes.

• Do not smoke or use tobacco

• Stay at a healthy weight for your height and age.

• Try to exercise moderately for at least 30 minutes a day.

• Avoid use of any medicine (esp. Pain killer) without your doctor advise

In summary, there is an age-related decline in kidney function, not all individuals will develop chronic kidney disease (CKD) with advancing age. Those who are genetically predisposed (with family history of kidney disease) or have diabetes or high blood pressure are more likely to have kidney dysfunction. Early detection and good management can increase the life of your kidneys.