Diabetic Kidney Disorder:

Diabetic Kidney Disease Diabetes is the single leading cause of kidney failure in the United States. Diabetes is a disease that affects the body’s ability to produce or respond to insulin, a hormone that allows blood glucose (blood sugar) to enter the cells of the body and be used for energy. Nephropathy, also called diabetic kidney disease, is a condition that affects one-third or more of people who have had Type 1 (juvenile) diabetes for at least 20 years. About 10 to 40 percent of people with Type 2 (adult onset) diabetes also have kidney disease.

In the United States diabetes is more common among certain ethnic groups, including: African-Americans, Hispanics, Pacific Islanders and Native Americans. The disease is extremely prevalent in the African-American community. Approximately 13 percent of all African-Americans have diabetes and one-third of this group are unaware that they have the disease. African-Americans suffer from kidney failure about four times more often than other ethnic groups.

Treatment for diabetic kidney disease focuses on slowing the progression to kidney failure. Controlling high blood pressure and blood sugar levels, participating in a doctor-supervised exercise and weight loss program and eating a special diet can help.

When kidney failure develops, the kidneys lose their ability to remove waste products from the body. The first signs of nephropathy are small amounts of protein in the urine and elevated levels of creatinine (a waste product) in the blood. Unfortunately, most people do not experience symptoms until their kidneys have lost much of their ability to function.

When kidneys function at only five to ten percent of their capacity, they can no longer process most of the waste in the body and cannot sustain a person’s life. This condition is called end-stage renal disease. Treatment options include either kidney dialysis or transplantation. In most cases, renal transplantation is often preferred for a better quality of life.

Are you at Risk for Diabetes?

Diabetes is a major risk factor for kidney disease. There are 18.2 million Americans with diabetes – and nearly one-third of them (5.2 million people) do not know it. African-Americans, Latinos, Native Americans, Asian Americans and Pacific Islanders are at higher risk for developing diabetes.

How does diabetes affect the kidneys?

Diabetes can affect the kidneys in a number of ways but one of the most important complications is diabetic nephropathy. This is a kidney condition that occurs only in people with diabetes mellitus and results in progressive damage to the small filtering units of the kidney (glomeruli).

This eventually leads to large amounts of protein in the urine, high blood pressure and declining kidney function. Even when drugs and diet are able to control diabetes, the disease can lead to nephropathy and kidney failure.

Diabetes is the most common cause of kidney failure in New Zealand. About 20% of people who need dialysis (artificial kidney treatment) or kidney transplantation have diabetic nephropathy.

What are the signs of diabetic kidney disease?

It is possible for individuals to have serious kidney damage without being aware of it. There may be no specific symptoms of diabetic kidney disease until the kidneys fail completely.

Early signs or risk factors include:

• albumin (a type of protein) in the urine
• tiredness
• swollen ankles
• breathlessness.

Symptoms related to kidney failure usually occur only in late stages of the disease, when kidney function has diminished. For many years before that point, kidney disease of diabetics exists as a silent process.

Damage to the kidneys is reflected in the amount of protein in the urine. Initially, the amount of protein is very small, but gradually, over a number of years, the amount of protein in the urine increases.

How does diabetes damage the kidneys?

Diabetes can cause damage to blood vessels and nerves and can prompt an increase in urine and kidney infections.

Damage to blood vessels: Even with the use of injected insulin, people who have had diabetes for some time often suffer from damage to the small blood vessels of the body. The delicate blood vessels in the filters of the kidney (the glomeruli) may be damaged. In the early stage, this damage is demonstrated by small amounts of protein in the urine.

Sometimes at a later stage, so much protein is lost from the blood that water from the blood moves into the body tissues and causes swelling (oedema). After a number of years, the kidneys' filters can become so damaged by diabetes that the kidneys fail completely. Because smoking also damages the blood vessels, it worsens the complications of diabetes. People with diabetes should try to stop smoking completely or never start.

Damage to nerves: Diabetes can also damage the nerves in many parts of the body. When the bladder is affected, it may be difficult to pass urine. If urine builds up in the bladder, the pressure can cause it to flow back into the kidneys and cause scarring to kidney tissue.

Infections: Urine of people with diabetes has a high sugar content. This encourages growth of bacteria and kidney.

Infections may occur. People with diabetes must take special care to ensure any infections are treated immediately.

Regular exercise and good diet will help to prevent kidney disease

Who can get diabetic nephropathy?

Diabetic nephropathy is a long-term complication of diabetes but only 20-30% of people with diabetes will develop it. It is not entirely understood why only a small number of people with diabetes develop diabetic nephropathy. However, a number of factors appear to increase the risk of kidney disease.

These include:

If a person's kidneys are about to fail, they might experience symptoms such as tiredness, nausea and vomiting. They may also find that they need less insulin than usual. When the kidneys fail, wastes and fluids will accumulate in the body and dialysis treatments or a kidney transplant is needed.

The survival of kidneys transplanted into diabetes patients is about the same as survival of transplants in people without diabetes. Dialysis for people with diabetes also works well. Even so, people with diabetes who receive transplants or dialysis may experience more medical problems and death because of other complications of the diabetes, such as damage to the heart, eyes, and nerves.

Some people with diabetic kidney failure will be suitable for a combined kidney and pancreas transplant. If successful, they will regain normal kidney function and will have normal blood sugar levels, meaning they can stop using insulin.

Why is high blood pressure a factor?

High blood pressure, or hypertension, is a major factor in the development of kidney problems in people with diabetes. Both a family history of, and the presence of high blood pressure, appear to increase chances of developing kidney disease. High blood pressure also accelerates the progress of kidney disease where it already exists.

High blood pressure is usually defined as blood pressure exceeding 140/90. The first number is the systolic pressure, the second number the diastolic. The terms systolic and diastolic refer to pressure in the arteries during contraction of the heart (systolic) and between heartbeats (diastolic).

Hypertension can be seen not only as a cause of kidney disease, but also as a result of damage created by the disease. Early detection and treatment of even mild hypertension is essential for people with diabetes.

How can kidney disease be slowed or prevented?

Certain tests can help to detect kidney damage at an early stage. There are also treatments which may help to delay kidney failure. It is usually necessary to start these treatments as soon as your doctor notices any of the early signs or risk factors. Therefore, you should stay in close touch with your doctor if you have diabetes.

To help prevent kidney damage

• Ensure that your diabetic control is excellent - follow your doctor's advice regarding insulin injections, medicines, diet, exercise and monitoring your blood sugar.
• control high blood pressure - have your blood pressure checked several times a year and preferably monitor it yourself at home. If blood pressure is high, follow your doctor's plan for keeping it at normal levels. Drugs used to lower blood pressure (anti-hypertensive drugs) can slow the progression of kidney disease
• make correct food choices - it is important to consult a doctor or dietitian to determine a suitable diet.
• stop smoking or don't start smoking.
• have urine infections treated immediately .
• control blood cholesterol and triglyceride levels with diet and medication if necessary
  drink alcohol in moderation only.
• aim to achieve and maintain your weight within the correct range for your height and age
• exercise regularly.
• have your urine, blood and blood pressure checked regularly by your doctor.
  ask your doctor to inform you of new developments in the treatment of diabetes.