Careful management of diabetes helps reduce the risk of developing kidney disease. Education and a commitment to monitoring diet, blood glucose levels and blood pressure are key. (For ways to protect your kidneys, see sidebar.)
The kidneys have been called the body’s master chemists, as they remove wastes, toxins and fluids from the blood stream. As blood flows through the kidneys, fluids and toxins are filtered out and eliminated through the urine. The kidneys also help the body use minerals and vitamins from food and to regulate hormone levels.
How can I protect
• Keep your blood pressure in a healthy range. For most people with kidney disease, blood pressure should be 130/80 or lower.
• Choose kidney-friendly foods and follow a heart-healthy diet. Those with Stage 4 or 5 kidney disease should follow a renal diet low in potassium, protein, phosphorus and sodium. Your diabetes educator or dietitian can help you choose appropriate foods.
• Watch your blood glucose levels. Keeping blood glucose levels in healthy ranges prevents further kidney damage. High glucose levels are one of the main causes of kidney damage in people with diabetes. Studies show that people with diabetes can reduce their risk of developing kidney damage by up to 50 per cent by carefully controlling blood glucose levels.
• Maintain a healthy weight by eating well and following a physical activity routine prescribed by your doctor.
• If you use tobacco, get help to stop. In addition to the harmful effects on your heart and lungs, smoking makes kidney disease worse.
The same constricting of blood vessels that causes complications of diabetes such as stroke and heart attack can affect tiny blood vessel filters in the kidneys. The resulting damage forces the kidneys to work harder and makes them much less efficient. Once kidney damage is extensive, people must have dialysis treatments or a kidney transplant.
Regular testing of how the kidneys are working helps protect them. People with diabetes should have their kidney function tested every year. Problems can be found early, while it is still possible to delay or avoid further damage. The first sign of diabetic kidney disease is usually protein in the urine. This can be found with a routine urine test. Anyone with diabetes should also have a simple kidney function blood test as part of the annual physical. (See sidebar for warning signs of kidney disease.)
Fortunately, if kidney damage is found early, it is possible to preserve remaining kidney function. Those who control their blood pressure and glucose levels while following a kidney-friendly diet can often delay – or even avoid – kidney problems.
Taking control of risk factors
Bryce Hill has had type 1 diabetes for more than 40 years. Nothing prepared him for the shock he experienced 30 years ago when he was told his kidneys had failed. He was advised to expect beginning dialysis within the year. That diagnosis made Bryce determined to go as long as possible without dialysis or a transplant. He and his wife Terri committed to making changes to his diet that would preserve his kidney function. Wanting to delay dialysis, they decided early to do everything they could to protect Bryce’s remaining kidney function.
Bryce followed a diet suitable for both kidney disease and diabetes. He carefully controlled his blood glucose and blood pressure levels. As a result, he was able to preserve his remaining kidney function for an incredible 19 years.
In 1992, 18 years later than his doctor had predicted, Bryce started dialysis. Within a year, he was lucky enough to receive a kidney transplant. This freed him from the challenge of scheduling regular dialysis treatments. To this day Bryce watches what he eats, hoping to keep his transplanted kidney working for as long as possible.
“It all comes down to how much you really want it,” Bryce says about the efforts he has made. “We figured it was worth the effort, and it has been.”
Understanding the risks of kidney disease
If damage is found early, it is possible to preserve kidney function. However, one challenge is that kidney disease often has no symptoms. For most people, the damage occurs slowly over many years. More advanced cases of kidney damage are diagnosed as kidney disease. Once kidney function is severely limited, kidney failure has begun. At that point, people can survive only a matter of weeks or months without treatment. Doctors monitor the progress of kidney disease according to the following stages.
Warning signs and symptoms of kidney disease
• Protein in the urine (measured by your doctor)
• High blood pressure
• Leg swelling, leg cramps
• Increased need to pass urine, especially at night
• Less need for insulin or medication to lower blood glucose
• Nausea and vomiting
Stages One and Two: Greater than 60 per cent kidney function
Stage Three: 60 to 30 per cent kidney function
Stage Four: 30 to 15 per cent kidney function
Stage Five: Less than 15 per cent kidney function
Treatment of kidney disease
Once kidney function falls to 10 to 15 per cent, most people feel ill and exhausted. It is like having a case of the flu you cannot shake. Once they have reached Stage Five of kidney disease, treatment to replace their kidney function must begin.
As little as 40 years ago, it was impossible for many to undergo treatment since there were so few medical options available. Happily, there are now three options available which can artificially replace kidney function.
Hemodialysis is the most common treatment for kidney disease in Canada. In this process, an artificial kidney (called a dialyzer) filters wastes, toxins and fluids from the blood. Tubing and catheters inserted into the blood vessels connect the person to the hemodialysis machine for about four hours at a time, three times a week. Most people visit a local hospital for treatment, though in-home treatments are becoming more popular. Right now, more than 13,000 Canadians use hemodialysis to replace kidney function.
Peritoneal dialysis is a form of dialysis where several treatments or ‘exchanges’ are done during the day. The dialysis solution is stored in the abdominal cavity. Toxins, wastes and fluids are absorbed by the liquid, which drains into the body through a catheter and plastic tubing. After a few hours, the used solution is drained and replaced. In most cases, people do four exchanges each day. Some use a special device to perform exchanges at home while they sleep. Almost 3,500 Canadians use peritoneal dialysis daily to replace kidney function.
Kidney transplants are an increasingly popular option for those whose kidneys have failed. There is no need for dialysis after a transplant, although anti-rejection drugs must be taken permanently.
There are a limited number of donated organs in Canada, so it is common to have a kidney transplanted from a family member (a living donation). Since it is possible to be healthy with only one kidney, living donation is a good option for many with kidney failure. Some choose and qualify to have a kidney and pancreas transplant. If successful, this can eliminate the need for insulin injections.
Kidney disease is affecting people with diabetes in record numbers. It has become a common reality for many Canadians. Each day 12 more Canadians learn that their kidneys have failed. An estimated 2.1 million Canadians have chronic kidney disease, with the number of new cases increasing by about seven per cent each year. Today, almost 30,000 Canadians are being treated for kidney failure.
It is important to remember that careful management of both your diabetes and your blood pressure can help delay or even prevent the onset of kidney disease. Ensure that your doctor is checking the levels of protein in your urine at least once per year as well.
To receive free information about kidney disease and diabetes, and to learn ways to reduce your risks for developing the disease, visit www.kidney.ca or contact The Kidney Foundation of Canada at 1-800-361-7494.