Black patients are more likely to develop acute kidney injury (AKI) following a percutaneous coronary intervention (PCI) than patients who are white or other races, according to findings from a large-scale analysis of Duke Health patients.

A higher risk of AKI incidence is linked with cardiac catheterization for all patients undergoing the procedure because of a commonly used contrast dye. But Clarissa J. Diamantidis, MD, a Duke nephrologist and researcher specializing in health inequities, says further research is essential to identify factors that predispose Black patients to disparate AKI risk and to take steps to mitigate those risks.

AKI is often a temporary condition, but it may contribute to future kidney complications, says Diamantidis, senior author of the analysis published in March 2021 in the Journal of the American Society of Nephrology. The study examined outcomes for more than 9,400 PCI procedures performed at Duke from 2003 to 2013. Duke nephrologists, cardiologists, and biostatisticians contributed to the analysis.

“In this study, we have identified what appears to be a trend that individuals who are Black are more likely to develop AKI,” says Diamantidis. “In the AKI literature, there is mounting evidence that certain groups have a greater risk of the injury. Individuals with diabetes or low kidney function are also at increased risk.”

To conduct the analysis, researchers quantified the association of race (white, Black, or other) with odds for AKI incidence within seven days after PCI. After adjusting for demographics, comorbidities, medications, and procedural characteristics, the study found that the odds for AKI incidence following PCI were substantially greater among Black patients than other racial groups. Baseline kidney function did not affect the likelihood of AKI incidence after PCI for Black patients.

“From a clinical perspective, the message is to be aware that elevated risk exists and undertake prophylactic steps to avoid injury,” Diamantidis says. “Make sure there is enough fluid volume before and after the catheter procedure to minimize the risk, for example.”

Because patients who are Black have a higher incidence of AKI as a result of PCI, Diamantidis recommends that they be monitored more carefully for the short and long-term consequences of developing AKI, which also contributes to hypertension, recurrent AKI, mortality, and increased hospitalization.

“We do not yet know precisely what these findings mean,” she adds. “The answer may lie in a social construct, not a biological one. But understanding the long-term significance of these findings is important, and a lot of work is going on in this realm.”

In addition to Diamantidis, the Duke research team included Joseph Lunyera, MBChB, MSc, a clinical epidemiologist, Patrick H. Pun, MD, MHS, a nephrologist, Kevin L. Thomas, MD, an electrophysiologist, Monique A. Starks, MD, a cardiologist, Karen Chiswell, PhD, a statistical scientist at Duke Clinical Research Institute (DCRI), and Robert Clare, a DCRI senior biostatistician.

The study was the first analytical kidney research project using the Duke Databank for Cardiovascular Disease (DDCD), a registry of all cardiac catheter procedure data for patients treated between July 1969 and March 2015 at Duke University Medical Center. The DDCD is the largest and oldest cardiovascular databank in the world. DDCD data provided detailed information related to the procedures, including the number of stents used, whether IV fluid was offered, and types of drugs involved, if any.

“This is a terrific resource to allow us to examine the effects of racial differences because of the comprehensive data collection related to a specific procedure,” Diamantidis says.

Diamantidis says the research project originated from the Duke O’Brien Center for Kidney Research during a search for alternative research databases. The project was supported by the Duke Center for Research to Advance Healthcare Equity (REACH).