March is National Kidney Month, a time to raise awareness about the prevention and early detection of kidney disease. Did you know that diabetes is the leading cause of kidney failure? The good news is that managing your diabetes well can help improve your health outcomes.
So how does diabetes cause kidney disease? The process goes like this: When our bodies digest protein, the procedure creates waste products. In the kidneys, millions of tiny blood vessels with even tinier holes in them act as filters. As blood flows through the blood vessels, small molecules such as waste products squeeze through the holes. These waste products become part of the urine. Useful substances, such as protein and red blood cells, are too big to pass through the holes in the filter and stay in the blood.
Diabetes, both type 1 and type 2, can damage this system. High levels of blood glucose cause stress on the filtering system in the kidneys. After many years, they start to leak, and things like protein that are supposed to stay in the bloodstream are lost in the urine. Having small amounts of protein in the urine is called microalbuminuria. This damage happens without any symptoms.
In time, the kidneys stop working well. Waste products then start to build up in the blood. Finally, the kidneys fail. This failure, end-stage renal disease (ESRD), is very serious and requires a kidney transplant or dialysis.
Whew! Still with us? We hope so, because as mentioned above, the better a person keeps diabetes under control, the lower the chance of getting kidney disease. Research has shown that tight blood glucose control reduces the risk of microalbuminuria by one third. Other studies have suggested that tight control can even improve microalbuminuria.
Since there are usually no symptoms associated with early kidney failure, lab tests are essential. If you have diabetes, talk to your health care provider about how often you should be tested. This can be done by either a blood test or a urine test.
A blood test measures the glomerular filtration rate (GFR), which tells how well the kidneys are filtering blood:
- A GFR of 60 or higher is in the normal range.
- A GFR below 60 may mean you have kidney disease.
- A GFR of 15 or lower may mean kidney failure.
Urine tests check for albumin, a type of protein found in blood. When the kidneys are healthy, they don’t let albumin pass into the urine. When the kidneys are damaged, they let some albumin pass into the urine. The less albumin in the urine, the better.
Now let’s talk prevention! You or a loved one living with diabetes can take the following steps to keep your kidneys healthy:
- Get the GFR (blood) and albumin (urine) tests for kidney disease as often as your health care provider recommends.
- Keep your blood glucose levels in your target range.
- High blood pressure is very hard on kidneys, especially for people with diabetes. Keep blood pressure your target range.
- Keep your cholesterol levels in the target range.
- Take medicines as directed by your provider.
- Cut back on salt. Aim for less than 2,300 milligrams of sodium, or less than one teaspoon, per day.
- Choose foods that are healthy for the heart, like fresh fruits, fresh or frozen vegetables, whole grains and low-fat dairy products.
- Limit alcohol intake.
- Be more physically active.
- If you’re overweight, take steps to lose weight. Being overweight makes the kidneys work harder.
- If you smoke, take steps to quit. Smoking can make kidney damage worse.
It’s time to think about your kidneys this month and be a health kidney champion! Learn more about prevention, detection and management of kidney disease from the National Kidney Disease Education Program and our website.