Diabetes and Kidney Disease: The Effects of High Blood Pressure
High blood pressure, or
hypertension, is a major factor in the development of kidney problems in people with
diabetes. Both a family history of hypertension and the presence of hypertension appear to increase chances of developing kidney disease. Hypertension also accelerates the progress of kidney disease in people who already have it.
In the past, hypertension was defined as
blood pressure exceeding 140 millimeters of mercury-systolic and 90 millimeters of mercury-diastolic. Professionals shorten the name of this limit to 140/90. The terms "systolic" and "diastolic" refer to pressure in the arteries during
contraction of the heart (systolic) and between heartbeats (diastolic).
The American Diabetes Association and the National Heart, Lung, and Blood Institute recommend that people with diabetes keep their blood pressure below 130/80.
Hypertension can be seen not only as a cause of kidney disease, but also as a result of damage created by the disease. As kidney disease proceeds, physical changes in the kidneys lead to increased blood pressure. Therefore, a dangerous spiral -- involving rising blood pressure and factors that raise blood pressure -- occurs. Early detection and treatment of even mild hypertension are essential for people with diabetes.
Diabetes and Kidney Disease: Preventing and Slowing Kidney Disease
Diabetes research studies have shown that preventing or slowing kidney disease can be achieved by:
- Using certain types of blood pressure medicine
- Eating a moderate-protein diet
- Intensive management of blood glucose.
Blood Pressure Medicines
Scientists have made great progress in developing methods that slow the onset and progression of kidney disease in people with diabetes. Drugs used to
lower blood pressure (antihypertensive drugs) can slow the progression of kidney disease significantly. Two types of
blood pressure medication have proven effective in slowing the progression of kidney disease:
- Angiotensin-converting enzyme inhibitors (ACE inhibitors)
- Angiotensin II receptor blockers (ARBs).
Many people require two or more drugs to control their blood pressure. In addition to an ACE inhibitor or an ARB, a diuretic is useful. Other drugs may also be needed, such as:
An example of an effective ACE inhibitor is
captopril (
Capoten®), which doctors commonly prescribe for treating kidney disease resulting from diabetes. The benefits of captopril extend beyond its ability to lower blood pressure; it may directly protect the kidney's glomeruli. ACE inhibitors have lowered proteinuria and slowed deterioration even in diabetic patients who did not have high blood pressure.
An example of an effective ARB is
losartan (
Cozaar®), which has also been shown to protect kidney function and lower the risk of cardiovascular events (such as a
stroke or
heart attack). Another example of an ARB used to treat diabetic nephropathy is
irbesartan (
Avapro®).
Any medicine that helps patients achieve a blood pressure target of 130/80 or lower provides benefits. Patients with even mild hypertension or persistent microalbuminuria should consult a physician about the use of antihypertensive medicines.