Kidney patients often excluded from heart trials

By Anthony J. Brown, MD

NEW YORK (Reuters Health) - Despite being at increased risk for illness and death, renal disease patients are frequently excluded from randomized trials looking at treatments for cardiovascular disease (CVD), according to a report released this week.

"At least 9 million people in the US have chronic kidney disease," senior author Dr. Chirag R. Parikh, from Yale University School of Medicine in New Haven, Connecticut, told Reuters Health. Moreover, "roughly 30 percent to 60 percent of CVD patients have renal disease," which is known to increase CVD-related death.

Although renal disease is common among CVD patients and is associated with worse outcomes, the present findings show that such disease is usually an exclusion criterion for CVD trials, Parikh noted. In addition, many trials simply do not include information on the renal function of participants.

Parikh's team conducted a MEDLINE search for randomized controlled trials published in 11 major medical journals between 1985 and 2005, looking specifically for trials investigating treatments for congestive heart failure and acute heart attack.

Of the 153 trials identified, 86 (56 percent) excluded patients with renal disease.

"Treatments for CVD may or may not work as well when renal disease is also present," Parikh noted. Therefore, there is a need for research in patients with both types of disease.

"We need to broaden the patient representation in CVD trials," he emphasized, adding that there are already simple classification systems for dividing trial participants into groups based on the extent of kidney disease.

SOURCE: Journal of the American Medical Association, September 20, 2006.