Diabetic nephropathy is a serious kidney-related complication of type 1 diabetes and type 2 diabetes. It is also called diabetic kidney disease. Up to 40 percent of people with diabetes eventually develop kidney disease.
Diabetic nephropathy affects the ability of your kidneys to do their usual work of removing waste products and extra fluid from your body. The best way to prevent or delay diabetic nephropathy is by maintaining a healthy lifestyle and treating your diabetes and high blood pressure.
Over many years, the condition slowly damages your kidneys' delicate filtering system. Early treatment may prevent or slow disease progression and reduce the chance of complications.
Your kidney disease may progress to kidney failure, also called end-stage kidney disease. Kidney failure is a life-threatening condition. At this stage your treatment options are dialysis or a kidney transplant.
In the early stages of diabetic nephropathy, you may not notice any signs or symptoms. In later stages, the signs and symptoms include:
- Worsening blood pressure control
- Protein in the urine
- Swelling of feet, ankles, hands or eyes
- Increased need to urinate
- Less need for insulin or diabetes medicine
- Confusion or difficulty concentrating
- Loss of appetite
- Nausea and vomiting
- Persistent itching
When to see a doctor
Make an appointment with your doctor if you have any signs or symptoms of kidney disease.
If you have diabetes, visit your doctor yearly for a urine test that detects protein. This helps determine how well the kidneys are functioning.
Diabetic nephropathy results when diabetes damages blood vessels and other cells in your kidneys.
How the kidneys work
Your kidneys contain millions of tiny blood vessel clusters (glomeruli) that filter waste from your blood. Severe damage to these blood vessels can lead to diabetic nephropathy, decreased kidney function and kidney failure.
Diabetic nephropathy causes
Diabetic nephropathy is a common complication of diabetes, types 1 and 2.
Over time the high blood sugar associated with untreated diabetes causes high blood pressure. This in turn damages the kidneys by increasing the pressure in the delicate filtering system of the kidneys.
Several factors may increase your risk of diabetic nephropathy, including:
- Diabetes, type 1 or 2
- High blood sugar (hyperglycemia) that's difficult to control
- High blood pressure (hypertension) that's difficult to control
- Being a smoker and having diabetes
- High blood cholesterol and having diabetes
- A family history of diabetes and kidney disease
Complications of diabetic nephropathy may develop gradually over months or years. They may include:
- Fluid retention, which could lead to swelling in your arms and legs, high blood pressure, or fluid in your lungs (pulmonary edema)
- A sudden rise in potassium levels in your blood (hyperkalemia)
- Heart and blood vessel disease (cardiovascular disease), possibly leading to stroke
- Damage to the blood vessels of the retina (diabetic retinopathy)
- Foot sores, erectile dysfunction, diarrhea and other problems related to damaged nerves and blood vessels
- Pregnancy complications that carry risks for the mother and the developing fetus
- Irreversible damage to your kidneys (end-stage kidney disease), eventually requiring either dialysis or a kidney transplant for survival
To reduce your risk of developing diabetic kidney disease:
- Treat your diabetes. With effective treatment of diabetes, you may prevent or delay diabetic kidney disease.
- Manage high blood pressure or other medical conditions. If you have high blood pressure or other conditions that increase your risk of kidney disease, work with your doctor to control them. Ask your doctor about tests to look for signs of kidney damage.
- Follow instructions on over-the-counter medications. When using nonprescription pain relievers, such as aspirin, ibuprofen (Advil, Motrin IB, others) and acetaminophen (Tylenol, others), follow the instructions on the package. For people with diabetic kidney disease, taking these types of pain relievers can lead to kidney damage.
- Maintain a healthy weight. If you're at a healthy weight, work to maintain it by being physically active most days of the week. If you need to lose weight, talk with your doctor about strategies for weight loss. Often this involves increasing daily physical activity and reducing calories.
- Don't smoke. Cigarette smoking can damage your kidneys and make existing kidney damage worse. If you're a smoker, talk to your doctor about strategies for quitting smoking. Support groups, counseling and medications can all help you to stop.
Your doctor will ask you about your signs and symptoms, conduct a physical exam, and ask about your medical history. He or she may refer you to a kidney specialist (nephrologist) or a diabetes specialist (endocrinologist).
To determine whether you have diabetic kidney disease, you may need certain tests and procedures, such as:
- Blood tests. If you have diabetes, you will need blood tests to monitor your condition and determine how well your kidneys are working.
- Urine tests. Urine samples provide information about your kidney function and whether you have too much protein in the urine. High levels of a protein called microalbumin may indicate your kidneys are being affected by disease.
- Imaging tests. Your doctor may use X-rays and ultrasound to assess your kidneys' structure and size. You may also undergo CT scanning and magnetic resonance imaging (MRI) to determine how well blood is circulating within your kidneys. Other imaging tests may be used in some cases.
- Renal function testing. Your doctor can assess your kidneys' filtering capacity using renal analysis testing.
- Kidney biopsy. Your doctor may recommend a kidney biopsy to remove a sample of kidney tissue. You will be given a local anesthetic. Then your doctor will use a thin needle to extract small pieces of kidney tissue for examination under a microscope.
The first step in treating diabetic nephropathy is treating your diabetes and, if needed, high blood pressure (hypertension). With good management of your blood sugar and hypertension, you can prevent or delay kidney dysfunction and other complications.
In the early stages of the disease, your treatment plan may include various medications, such as those that help:
- Control high blood pressure. Medications called angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) are used to treat high blood pressure. Using both of these is not advised because of increased side effects. Studies support the goal of a blood pressure reading of 140/90 millimeters of mercury (mm Hg) or less.
- Manage high blood sugar. Several medications have been shown to help control high blood sugar in people with diabetic nephropathy. Studies support the goal of an average hemoglobin A1C (HbA1C) of less than 7 percent.
- Lower high cholesterol. Cholesterol-lowering drugs called statins are used to treat high cholesterol and reduce protein in the urine.
- Foster bone health. Medications that help manage your calcium phosphate balance are important in maintaining healthy bones.
- Control protein in urine. Medications can often reduce the level of the protein albumin in the urine and improve kidney function.
Your doctor may recommend follow-up testing at regular intervals to see whether your kidney disease remains stable or progresses.
Treatment for advanced diabetic kidney disease
If your disease progresses to kidney failure (end-stage kidney disease), your doctor will help you transition to care focused on either replacing the function of your kidneys or making you more comfortable. Options include:
- Kidney dialysis. This treatment is a way to remove waste products and extra fluid from your blood. The two main types of dialysis are hemodialysis and peritoneal dialysis. The first method is more common and requires that you visit a dialysis center and be connected to an artificial kidney machine about three times a week. Each session takes three to five hours. The second method may be done at home.
- Transplant. In some situations, the best option is a kidney transplant or a kidney-pancreas transplant. If you and your doctor decide on transplantation, you will be evaluated to determine whether you're eligible for this surgery.
- Symptom management. If you choose not to have dialysis or a kidney transplant, your life expectancy generally would be only a few months. You may receive treatment to help keep you comfortable.
Potential future treatments
In the future, people with diabetic nephropathy may benefit from treatments being developed using regenerative medicine. These techniques may help reverse or slow kidney damage caused by the disease. For example, some researchers think that if a person's diabetes can be cured by a future treatment such as pancreas islet cell transplant or stem cell therapy, kidney function may improve.
In addition, researchers are testing in people stem cells and several new medications for diabetic nephropathy.
Lifestyle and home remedies
Lifestyle behaviors can support your treatment goals. Depending on your situation, kidney function and overall health, these actions may include:
- Being active most days of the week. With your doctor's advice, aim for at least 30 minutes of physical activity most days of the week.
- Adjusting your diet. Talk with a dietitian about limiting intake of sodium, choosing lower potassium foods and limiting the amount of protein you eat.
- Quitting smoking. If you're a smoker, talk with your doctor about strategies for quitting smoking.
- Maintaining a healthy weight. If you need to lose weight, talk with your doctor about strategies for weight loss. Often this involves increasing daily physical activity and reducing calories.
- Taking a daily aspirin. Talk with your doctor about whether a daily low-dose aspirin is right for you.
Being vigilant. Alert doctors unfamiliar with your medical history that you have diabetic nephropathy. They can take steps to protect your kidneys from further damage due to medical tests that use contrast dye (such as angiogram and computerized tomography scan).
Also be able to recognize when you have a urinary tract infection and seek treatment promptly.
Coping and support
If you have diabetic nephropathy, here are some steps that may help you cope:
- Connect with other people who have diabetes and kidney disease. Ask your doctor about support groups in your area. Or contact organizations such as the American Association of Kidney Patients, the National Kidney Foundation or the American Kidney Fund for groups in your area.
- Maintain your normal routine, when possible. Try to maintain a normal routine, doing the activities you enjoy and continuing to work, if your condition allows. This may help you cope with feelings of sadness or loss that you may experience after your diagnosis.
- Talk with someone you trust. Living with diabetic kidney disease can be stressful, and it may help to talk about your feelings. You may have a friend or family member who is a good listener. Or you may find it helpful to talk with a faith leader or someone else you trust. Consider asking your doctor for a referral to a social worker or counselor.
Preparing for an appointment
If you have signs and symptoms of kidney disease, make an appointment to see your doctor.
What can you do
Here's some information to help you prepare for your appointment.
- Be aware of pre-appointment restrictions. When you make the appointment, ask if you need to do anything beforehand, such as limit your diet.
- List your symptoms, including any that seem unrelated to your kidneys or urinary function.
- List all medications, vitamins or supplements you take, including doses.
- List key medical history, including a family history of diabetes or kidney disease.
- Be prepared to discuss your diet and exercise habits. If you don't already eat well and exercise, be ready to talk with your doctor about challenges you might face in getting started.
- Ask a family member or friend to come with you. He or she may hear something that you missed or forgot.
- List questions to ask your doctor.
For diabetic nephropathy, some basic questions to ask your doctor include:
- What's the level of damage to my kidneys?
- Is my kidney function worsening?
- Do I need more tests?
- What's causing my condition?
- Can the damage to my kidneys be reversed?
- What are my treatment options?
- What are the potential side effects of each treatment?
- I have other health conditions. How can I best manage them together?
- Do I need to eat a special diet?
- Can you refer me to a dietitian who can help me plan my meals?
- Do I need to see a specialist?
- Is there a generic alternative to the medicine you're prescribing?
- Do you have any brochures or other printed material that I can have? What websites do you recommend?
- How often do I need to schedule follow-up visits and testing?
Don't hesitate to ask any other questions during your appointment as they occur to you.
What to expect from your doctor
Your doctor may ask you questions, such as:
- Do you have diabetes or high blood pressure? If so, for how long?
- Are you experiencing any symptoms, such as changes in your urinary habits or unusual fatigue?
- How long have you had symptoms?
- What, if anything, seems to improve your symptoms?
- What, if anything, appears to worsen your symptoms?