UC study finds hyperkalemia common and life-threatening in organ transplant recipients

Solid organ transplant (SOT) recipients experience an increased incidence of hyperkalemia—higher than normal potassium levels in the blood—caused by both pathophysiological or medication related mechanisms, according to a study by researchers from the University of Cincinnati (UC) Division of Nephrology Kidney CARE Program. The research was presented at the American Society of Nephrology meeting in San Diego, Oct. 27, 2018.

“Hyperkalemia is common in transplant recipients admitted to acute care, and can be potentially devastating to the patients,” says Charuhas Thakar, MD, professor and director of the UC Division of Nephrology Kidney CARE Program at the UC College of Medicine and senior author of the study. “The risk of hyperkalemia has been well recognized in the past. However, our study is among the largest studies in solid organ transplant recipients to investigate the incidence and outcomes associated with this abnormality.”

In a multi-center sample of approximately 15,000 SOT recipients, the investigators examined the incidence and outcomes of hyperkalemia. Specifically, they examined first hospitalizations after transplant surgery. This is among the largest studies of SOT recipients across multiple centers in the United States, with 64.7 percent being kidney transplant patients, 17.2 percent liver, 8 percent heart patients and 10.1 percent being other SOT recipients.

Overall, 16 percent experienced moderate to severe hyperkalemia, defined as potassium levels above 5.5 milliequivalents per liter. Compared to the mortality of 2 percent in patients without hyperkalemia, mortality was six percent in those with hyperkalemia. Hyperkalemia also increased the risk of 30-day readmissions.

“There are limitations to this study,” says Thakar. “Observational studies and associations can have unmeasured confounders, and future studies need to identify specific modifiable factors that can mitigate the risks of this rather common electrolyte disorder. Additionally, efforts should be made to prevent patient harm from this potentially treatable condition.”

The study was presented by Masaaki Yamada, MD, a transplant fellow in the Division of Nephrology and lead investigator. Coinvestigators of the research include Amit Govil, MD, Silvi Shah, MD, and Taranpreet Kaur, MD, all in the Division of Nephrology; Karthik Meganathan and Annette Christianson, both research associates in the Center for Health Informatics; and Anthony Leonard, PhD, adjunct associate professor in the Department of Family and Community Medicine, all in the UC College of Medicine. Part of this work was supported by a fellowship grant award funded by Relypsa.