Understanding Kidney Disease
Too often, diabetes leads to kidney disease. But it doesn't have to. When kidney problems are caught early, you can take steps to prevent more serious kidney disease. That's why it's important to check the health of your kidneys with a microalbumin test.
The kidneys filter and clean about 50 gallons of blood every day, carefully removing the body's toxic waste products. Diabetes can be hard on the kidneys, and when blood sugar is high, they filter more blood than normal. Over time, their tiny filters start to leak. When this happens, substances that normally stay in the blood pass into the urine. Albumin, a protein, is one of those substances. The presence of small amounts of albumin in the urine—a condition called microalbuminuria—is an early sign of kidney damage.
If early damage isn't detected and treated, the kidneys become more diseased over time. Large amounts of albumin leak into the urine. This is called macroalbuminuria. After several years, the kidneys may shut down entirely. The only treatments at that point are dialysis, the artificial cleansing of the blood by a machine, or a kidney transplant.
Early kidney disease has no symptoms, so you need a microalbuminuria test to check kidney function. The test measures the amount of albumin in your urine. You may be asked to provide a fresh sample of urine while you're at your health care provider's office. This is called a random, or spot, sample. Or you may be asked to collect your urine for a certain period of time, such as four hours, 24 hours or overnight. This is called a timed sample. You'll be given a container and instructions for collecting your urine. Little or no albumin in the urine means your kidneys are normal. A moderate amount indicates early kidney damage. A large amount signals more severe kidney disease.
How often to test
The American Diabetes Association recommends an annual microalbuminuria test for people with type 2 diabetes. People with type 1 diabetes should be tested once a year if they are older than age 10 or have had diabetes for 5 years or longer. If you take certain medications, have high blood pressure, or have more albumin in your urine than is normal, you may need to be tested more often.
If your test shows that you have microalbuminuria, it's crucial to get treatment to slow the progression of kidney disease. You'll need to keep your glucose controlled as much as possible. Staying in your target range can cut the risk for developing more serious kidney disease by half. To reduce stress on your kidneys, you'll also need to control your blood pressure and eat only moderate amounts of protein. Maintaining good heart health by lowering cholesterol and managing high blood pressure is also important for controlling microalbuminuria. And if you smoke, talk with your health care provider about ways to quit.
Two drugs are commonly used to slow the progression of kidney disease: angiotensin-converting enzyme inhibitors and angiotensin receptor blockers. Other drugs may be used to control blood pressure, such as calcium channel blockers, beta-blockers, and diuretics.
Keep your kidneys healthy
If you have healthy kidneys now, staying in your glucose target range can cut your risk for microalbuminuria by a third. Like diabetes, hypertension is a major cause of kidney disease. Take blood pressure medication as directed, get regular exercise, and follow a heart-healthy eating plan. You can do a lot right now to prevent or delay kidney disease.
- MMI board-certified, academically affiliated clinician
- Turley, Ray, BSN, MSN