The jury has been out on whether people who are at risk for diabetic kidney disease but have normal blood pressure should use angiotenisin converting enzyme (ACE) inhibitors. Traditionally, ACE inhibitors have been used to treat people with hypertension, but lately, they have become a mainstream treatment option of diabetic kidney disease.
The American Diabetes Association (ADA) recommends the use of ACE inhibitors in patients with diabetic kidney disease only if they have high blood pressure. The National Kidney Foundation (NKF), on the other hand, recommends the use of ACE inhibitors in diabetic patients at risk for kidney disease who have normal blood pressure. Leonard G. Feld, MD, is a renal disease expert at the Atlantic Health System who agrees with the NKF.
“Waiting for these patients with kidney disease to develop high blood pressure and then loading them with the drug [ACE inhibitors] would be a bad idea, as most of the patients would be in the advanced stage of the disease by then,” says Feld.
The first sign of kidney disease in a patient with diabetes is the appearance of protein in the urine. If the protein in the urine is greater than 30 mg/dl per day, the patient is considered to be in the early stages of diabetic kidney disease.
A multicenter European study was conducted on patients with diabetic kidney disease to determine the efficiency of ACE inhibitors. The patients were divided into two groups: one group was treated with ACE inhibitors while the other was given a placebo. The results of the study demonstrated that 30 percent of the placebo group developed significant complications in their kidneys while only 10 percent of the ACE inhibitor group developed similar complications.
Kidney disease can cause diabetes-related deaths. Feld approximates that 30 to 40 percent of all people with diabetes develop some kind of decline in kidney function.
“The key to success in the treatment with ACE inhibitors is early detection and prompt intervention at this correctable phase,” says Feld.
Researchers have yet to discover how ACE inhibitors have a beneficial effect on the kidneys of people with diabetes. ACE inhibitors have caused problems in pregnant women and in patients whose blood vessel to the kidney is obstructed. Feld cautions that prescribing ACE inhibitors to these patients would be catastrophic and that physicians need to be extremely cautious when dealing with this segment of the diabetes population. Additionally, diabetic patients with kidney disease who take ACE inhibitors should be closely monitored for elevations in blood potassium and creatinine levels.