Older Americans with high blood pressure and moderate to severe chronic kidney disease have a greater chance of developing heart disease than people with normal kidney function. This finding is one of three in a new paper published in the Feb. 7 issue of the Annals of Internal Medicine.
The study also found these patients are at higher risk for developing heart disease than kidney failure (end stage renal disease). Lastly, it found for the first time that new types of drugs such as ACE inhibitors and calcium-channel blockers are no better than older type diuretic drugs, also called water pills, in preventing heart disease, and may be even less effective at preventing heart failure in patients with chronic kidney disease.
Lead author of the study is Mahboob Rahman, M.D., M.S., of Case Western Reserve University School of Medicine, University Hospitals of Cleveland and the Louis Stokes Cleveland VA Medical Center. The study was sponsored by the National Heart Lung and Blood Institute and coordinated by the Clinical Trials Center at the University of Texas School of Public Health in Houston.
The study looked at more than 31,000 men and women 55 years and older who have high blood pressure and one other risk factor of cardiovascular disease, such as diabetes. A blood test was used to determine kidney function and severity of disease.
Patients with moderate chronic kidney disease had a 38 percent greater chance of developing heart disease and a 35 percent increase in overall cardiovascular disease (which includes heart disease, stroke, heart failure and others) than those with normal kidney function. In addition, patients with moderate to severe chronic kidney disease were twice as likely to develop heart disease than to experience kidney failure.
Rahman said the researchers are not quite sure why moderate and severe kidney disease leads to greater risk in heart disease. "It may be related to other factors associated with renal failure, such as anemia or abnormalities of calcium or phosphorus metabolism, for example. We are participating in other ongoing studies to establish the connections," he said.
The study also confirmed other earlier findings that diuretics are as effective as or better for preventing cardiovascular disease than newer drugs.