With a dramatic increase in the number of Americans being diagnosed with diabetes, millions of Americans also are at risk for kidney disease - and they may not realize it.
Today, nearly 24 million Americans are diagnosed with diabetes, and 57 million have pre-diabetes. According to the American Diabetes Association, 10-21 percent of all people with diabetes have kidney disease or nephropathy. Each year in the United States, more than 100,000 people are diagnosed with kidney failure, a serious condition in which the body can no longer eliminate wastes. Diabetes is the leading cause of kidney failure, accounting for approximately 44 percent of new cases.
Diabetic nephropathy is a progressive disease that typically takes several years to develop. When blood sugar levels reach 180 and above, the kidneys work to filter the excess glucose or sugar from the body because the sugar is seen as a “waste product.” This produces frequent urination, one of the symptoms of high blood sugar or hyperglycemia.
Since high levels of blood sugar force the kidneys to filter too much blood, all this work is hard on the filters in the kidneys, and they begin to leak. Having small amounts of protein in the urine is called microalbuminuria. When kidney disease is diagnosed early, several treatments may keep the kidneys from getting worse. Having large amounts of protein in the urine is called macroalbuminuria. When kidney disease is detected later, end-stage renal disease typically follows. When kidney failure occurs, individuals must undergo either dialysis or a kidney transplant.
Most people with type 2 diabetes also have high blood pressure and high cholesterol. Therefore, controlling blood pressure is very important in reducing the risk for kidney disease. Blood pressure has a dramatic effect on the rate at which kidney disease progresses. Both a family history of high blood pressure and presence of high blood pressure can increase the risk for developing kidney disease. Hypertension also increases the progress of kidney disease when it already exists. Early detection and treatment of even mild hypertension is essential for people with diabetes. Just by detecting and treating early diabetic kidney disease and lowering blood pressure can reduce kidney function decline by 30-70 percent. The ADA recommends individuals with diabetes maintain blood pressure at 130/80 and below to help protect the kidneys. Medications -- including ACE inhibitors and ARBs -- used to lower blood pressure also can slow the progression of kidney disease.
Individuals with diabetes also can protect their kidneys by maintaining blood sugar levels within normal range. Research has shown that blood sugar control reduces the risk of microalbuminuria by one-third. In people who already had microalbuminuria, the risk of progressing to macroalbuminuria decreased by 50 percent.
Diabetics need to have their kidneys checked yearly at the doctor’s office. Also, have yearly lab work. Results of tests are used to estimate the glomerular filtrate rate (GFR), a measure of kidney function. All adults are reminded to make a doctor’s appointment immediately for bladder or kidney infections.
Dawn Hollaway is a registered nurse and certified diabetes educator at the Blount Memorial Diabetes Management Center, where she also serves as program coordinator. She also holds a master’s degree in public health.