Hyperkalemia on admission to a cardiac intensive care unit (CICU) is associated with higher in-hospital and post-discharge mortality, investigators concluded.
In a study of 9681 patients admitted to a CICU from January 2007 to December 2015, a team led by Jacob C. Jentzer, MD, of Albany Medical College in Albany, New York, found that patients with admission hyperkalemia had significant 44% increased odds of in-hospital mortality and significant 20% increased risk of post-discharge mortality compared with normokalemic patients, after adjusting for illness severity and renal function. Hypokalemia was not associated with in-hospital or post-discharge mortality.
“Elevated admission potassium levels only slightly above the upper limit of normal were associated with higher short- and long-term mortality, emphasizing the importance of mild hyperkalemia as a predictor of adverse outcomes,” the authors concluded. “This demonstrates that admission potassium levels may be a marker for illness severity that can help clinicians in prognostication and risk assessment in the CICU.”
The study population, which was 64% male, had a mean age of 67 years. The in-hospital death rate was 9%. At admission, 1187 patients (12.3%) had hyperkalemia (potassium values of 5.0 mEq/L or above) and 719 (7.4%) had hypokalemia (potassium values less than 3.5 mEq/L).
Brueske B, Sidhu MS, Schulman-marcus J, et al. Hyperkalemia is associated with increased mortality among unselected cardiac intensive care unit patients. J Am Heart Assoc. 2019; 8(7):e011814.