Nephropathy, or kidney disease, is among the most serious complications for many people with diabetes. It’s the leading cause of kidney failure in the United States. According to the National Kidney Foundation, 465,000 Americans have end-stage kidney disease and are living by means of dialysis. Nephropathy has few early symptoms or warning signs, similar to other diseases associated with type 2 diabetes. Damage to the kidneys from nephropathy can occur for as long as a decade before the first symptoms appear.
According to Dr. Charles M. Clark, Jr., M.D., former chairman of the National Diabetes Education Program, “A person can have type 2 diabetes for 9 to 12 years before it’s discovered. During those years, harmful changes are already occurring, causing 5 to 10 percent to [already] have kidney disease at the time of diagnosis.”
Often, no symptoms of kidney disease appear until the kidneys are no longer functioning properly. Symptoms that indicate your kidneys could be at risk include:
- fluid retention
- swelling of the feet, ankles, and legs
- a poor appetite
- feeling exhausted and weak most of the time
- frequent headaches
- upset stomach
- difficulty concentrating
Early diagnosis of kidney disease is essential for preserving good health. If you have prediabetes, type 2 diabetes, or other known diabetes risk factors, your kidneys are already overworked and their function should be tested annually.
Besides diabetes, other risk factors for kidney disease are:
- uncontrolled high blood pressure
- uncontrolled high blood glucose
- high cholesterol
- a family history of kidney disease
- a family history of heart disease
- cigarette smoking
- advanced age
A higher prevalence of kidney disease exists among:
- American Indians
- Hispanic Americans
Kidney disease doesn’t have just one specific cause. Experts believe its development is likely associated with years of uncontrolled blood glucose. Other factors likely play important roles as well, such as genetic predisposition.
The kidneys are the body’s blood filtration system. Each is made up of hundreds of thousands of nephrons that clean the blood of waste. Over time, especially when a person has type 2 diabetes, the kidneys become overworked because they’re constantly removing excess glucose from the blood. The nephrons become inflamed and scarred, and they no longer work as well.
Soon, the nephrons can no longer fully filter the body’s blood supply. Material that would typically be removed from the blood, such as protein, passes into the urine. Much of that unwanted material is a protein called albumin. Your body’s levels of albumin can be tested in a urine sample to help determine how your kidneys are functioning.
A small amount of albumin in the urine is referred to as microalbuminuria. When larger amounts of albumin are found in the urine, the condition is called macroalbuminuria. The dangers of kidney failure are much greater with macroalbuminuria, and end-stage renal disease (ESRD) is a risk. Treatment for ERSD is dialysis, or having your blood filtered by a machine and pumped back into your body.
The main ways to prevent diabetic nephropathy include the following:
The best way to preserve kidney health is to watch your diet carefully. People with diabetes who have partial kidney function need to be even more vigilant about maintaining:
- healthy blood glucose
- blood cholesterol
- lipid levels
Maintaining a blood pressure of less than 130/80 is also essential. Even if you have mild kidney disease, it may be made much worse by hypertension. Follow these tips to help lower your blood pressure:
- Eat foods low in salt.
- Don’t add salt to meals.
- Lose weight if you’re overweight.
- Avoid alcohol.
Your doctor may recommend that you follow a low-fat, low-protein diet.
Based on your doctor’s recommendations, daily exercise is also a must.
Most people with type 2 diabetes who have high blood pressure take angiotensin converting enzyme (ACE) inhibitors for heart disease treatment, such as captopril and enalapril. These drugs also have the potential to slow the progression of kidney disease. Doctors also commonly prescribe angiotensin receptor blockers.
If you smoke cigarettes, you should stop immediately. According to a study published in the , cigarette smoking is now an established risk factor for developing kidney disease.