A commonly used heart drug can halve the risk of death, dialysis or kidney transplants resulting from kidney disease among diabetics, dramatically improving the quality of life and significantly reducing the cost of medical care, researchers report.
An estimated 30 percent of the 14 million diabetic Americans will develop kidney disease, so the new treatment has the potential to significantly alter the treatment of tens of thousands of patients every year, said Dr. Edmund J. Lewis of the Rush-Presbyterian-St. Luke's Medical Center in Chicago. Dr. Lewis headed the trial, conducted using 409 patients at 30 U.S. medical centers.
"We are very excited about these results, which have far exceeded our expectations," Dr. Lewis said yesterday at a news conference marking publication of their report today in the New England Journal of Medicine. In a later interview, he urged that physicians begin using the drug, captopril, immediately.
"Unless there is some very good reason to the contrary, the stakes are so high that, in my opinion, diabetic patients who show any evidence of renal involvement should get the drug," he said. He would even recommend it for diabetics who have not yet developed kidney problems, even though such patients were not studied in the trial. "If my kid had diabetes, I wouldn't wait to find out if he was going to be in the 30 percent who develop kidney disease. I would give him captopril."
Others were equally enthusiastic. "For everyone with diabetes, these are striking and important findings . . . that are expected to establish a new standard of care for these patients and offer hope for a longer and better quality of life," said Dr. James R. Gavin III, president of the American Diabetes Association.
"This study provides the first solid evidence that we now have the means to slow the progression of the most dreaded complication of insulin-dependent diabetes," added Dr. Gary Striker of the National Institute of Diabetes and Digestive and Kidney Diseases.
Diabetes results when the pancreas does not produce enough insulin to regulate the use and storage of sugars by body tissues. As many as 1 million Americans have type 1 diabetes, also known as insulin-dependent diabetes, in which daily insulin shots are necessary to control blood sugar levels. The remaining 13 million have type 2 diabetes, which can often be controlled by diet and exercise, or by the use of drugs that stimulate the pancreas to produce more insulin.
Both types of diabetics suffer a variety of complications thought to be caused by poor control of blood sugar levels. These include blindness, nerve damage in the arms and legs and kidney damage -- also known as end-stage renal disease or ESRD -- which is often the most devastating. There are currently no drugs available to delay or prevent the onset of kidney damage.
An estimated 210,000 Americans now have ESRD. Diabetes is the leading cause, accounting for about 35 percent of new cases annually. In ESRD, the kidneys fail and either dialysis or a kidney transplant is required for survival. The cost of caring for such patients in the United States now totals $7.2 billion annually, according to the National Kidney Foundation.
Captopril is a member of a family of drugs called angiotensin-converting enzyme or ACE inhibitors. The drug relaxes capillaries, including those in the kidney, so that blood can flow more freely. It is widely used for controlling high blood pressure.