WASHINGTON—Excursions from target range serum potassium in patients on hemodialysis (HD) may better predict impending death than a single potassium measurement or time-averaged potassium values, according to new study findings presented at the American Society of Nephrology’s Kidney Week 2019 meeting.
Using data from the Dialysis Outcomes and Practice Patterns Study (DOPPS) phases 4–6 spanning the years 2009 to 2018, Angelo Karaboyas, MS, of Arbor Research Collaborative for Health in Ann Arbor, Michigan, and collaborators assessed the number of hyperkalemia excursions patients experienced over 4-month periods. They used 3 definitions: serum potassium more than 5.0, more than 5.5, and more than 6.0 mEq/L. The DOPPS cohort of 61,897 HD patients yielded 243,886 four-month periods for analysis.
A hyperkalemia excursion was serum potassium more than 5.0, more than 5.5, or more than 6.0 mEq 58%, 30%, and 12%, of the time, respectively. Hyperkalemia excursions of more than 5.5 mEq/L occurred most frequently in Russia (68%) and least frequently in the United States (25%) among the 21 countries represented in DOPPS.
Patients who experienced hyperkalemia excursions tended to be younger, with longer dialysis vintage and higher serum levels of albumin and phosphorus.
In adjusted models, mortality over the 4 months following any hyperkalemia excursion was 10% to 20% higher than after periods of normal potassium. Death risk was 20% to 30% higher in periods with 2 or more hyperkalemia excursions. The team adjusted results for hypokalemia excursions (serum potassium less than 4.0) and other markers of malnutrition.
Clinicians typically determine hyperkalemia (HK) using a single potassium (K) measurement or time-averaged K values.
“This method to assess target K achievement may be more sensitive at identifying patients with greater mortality risk over short-term intervals at lower thresholds (5.1–5.5 mEq/L) than previously reported, prompting reassessment of existing HK severity ranges and exploration of strategies to avoid HK excursions,” Karaboyas’ team concluded.
Karaboyas A, Robinson BM, James G, et al. Hyperkalemia excursions and mortality in hemodialysis patients: Results from the DOPPS. Presented at the American Society of Nephrology’s Kidney Week 2019 meeting held November 5-10 in Washington DC. Abstract SA-OR067.