DEAR DOCTOR K: I have diabetes. My doctor says I’m at risk for diabetic nephropathy. What is that? What can I do to prevent it?
DEAR READER: Diabetic nephropathy is kidney disease that is a complication of diabetes.
Your kidneys are made up of hundreds of thousands of small tubes that filter your blood and help remove waste from your body. In people with poorly controlled diabetes, these structures thicken and become scarred. Over time, the kidneys lose their ability to remove waste products from the blood.
To prevent diabetic nephropathy, you need to control your blood sugar. Diet and exercise can powerfully lower it. I’m sure you already know what you should be doing in terms of lifestyle changes, but it’s worth repeating. Aim to:
— Achieve and maintain a healthy weight.
— Exercise regularly. Aim for at least 30 minutes of moderate intensity exercise, most days of the week.
— Eat a healthy diet:
*Avoid added sugars.
*Minimize refined carbohydrates like white bread and white rice.
*Minimize saturated fats and cholesterol.
*Limit calories.
*Emphasize vegetables, fruits, whole grains and healthy oils.
You also need to control your blood pressure. Like diabetes, high blood pressure injures the kidneys. In fact, the combination of both diabetes and high blood pressure is particularly damaging to the kidneys.
Even worse, your kidneys play a crucial role in the body’s control of blood pressure. If they are damaged further, your blood pressure can get worse. It’s a vicious cycle. Failing to take care of your blood pressure leads to more kidney damage. That leads to higher blood pressure — and that leads to more kidney damage. You get the point. Aim to keep your blood pressure below 130/80 mmHg.
Lifestyle changes to control blood pressure begin with weight loss, regular exercise and a healthy diet. In addition, cut back on salt in your diet, limit alcohol and quit smoking.
Any person who has diabetes and high blood pressure should also take one of two types of blood pressure medications. These drugs — angiotensin-converting enzyme inhibitors (ACE inhibitors) and angiotensin receptor blockers (ARBs) — protect against kidney damage in ways that go beyond lowering your blood pressure.
You also should avoid medications that can have harmful side effects on the kidneys. For example, ask your doctor if you should avoid nonsteroidal anti-inflammatory drug (NSAID) pain relievers such as ibuprofen (Advil, Motrin).
A low-protein diet, in which protein contributes 10 to 12 percent or less of total calories, also may slow or stop the progression of kidney disease.
Once the damage is done, kidney disease can’t be reversed. But if you do develop diabetic nephropathy, good blood sugar and blood pressure control, and treatment with one of the two types of medications I mentioned, can slow its progression.
Dr. Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK.com, or write: Ask Doctor K, 10 Shattuck St., Second Floor, Boston, MA 02115.
Commented