ST. JOHN'S, NEWFOUNDLAND—Older patients who have coronary angiography and then experience acute kidney injury (AKI) are significantly less likely to receive cardiovascular medications than their counterparts who do not develop AKI, a new study shows.

An analysis of Alberta residents over age 65 who received coronary angiography for an acute coronary syndrome between November 1, 2002 and March 31, 2008 demonstrated that those who developed AKI during their hospitalization were 23% less likely than those without AKI to receive an ACE inhibitor or angiotensin receptor blocker (ARB). They were also 22% less likely to receive anti-platelet medication, 19% less likely to receive a statin, and 15% less likely to be prescribed a beta-blocker.

The results are independent of baseline renal function and whether the patients had received the medications prior to hospitalization, according to findings presented at the Canadian Society of Nephrology's 2012 annual meeting.

“A possible explanation for this could be concern that use of the cardiovascular medications could affect renal function and worsen outcomes. The patients were substituted to other classes of medications—but were not switched back prior to discharge,” investigator Kelvin Leung, MD, a nephrology fellow at the University of Calgary, told Renal & Urology News.

Dr. Leung and other members of the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease and the Alberta Kidney Disease Network excluded from their database analysis individuals who were on dialysis or who had received a kidney transplant. They included 5,991 patients who did not develop AKI and another 898 who did.

The team also determined that AKI patients had a significantly lower cumulative incidence of the use of statins, beta-blockers, ACE inhibitors/ARBs, and anti-platelet agents.

An analysis of cardiovascular-medication-naïve patients who developed AKI showed that they also were significantly less likely than their medication-naïve non-AKI counterparts to receive the potentially life-saving agents.

Additionally, the investigators found that the lower rates of heart medication use among AKI patients generally was not related to the presence of diabetes, heart failure, baseline estimated glomerular filtration rate, or overall medication use. The only exception was a significantly decreased use of ACE inhibitors among patients with preexisting heart failure who developed AKI.

Dr. Leung said he and his co-investigators are “unsure if this translates into an effect on mortality,” and that this should be elucidated in future research.

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