Real-World Evaluation of Patiromer for the Treatment of Hyperkalemia in Hemodialysis Patients

INTRODUCTION: Patiromer is a potassium (K(+)) binding polymer indicated for treating hyperkalemia. Among patients receiving chronic hemodialysis (HD), this study aimed to identify patient characteristics associated with patiromer initiation, describe patiromer utilization, and analyze serum K(+) pre- and post-patiromer initiation. METHODS: In a retrospective cohort study, using electronic health record data from a large dialysis provider in the United States (study period: December 21, 2015, to December 20, 2016), HD patients were included who had a medication order for patiromer, sodium polystyrene sulfonate (SPS), or laboratory evidence of hyperkalemia (no K(+) binder [NoKb] cohort). The index date was the first order for patiromer/SPS, or the first K(+) ≥5.0 mEq/l (NoKb cohort), respectively. Using multivariable logistic regression, we identified patient characteristics associated with patiromer initiation. We evaluated patiromer utilization using Kaplan-Meier methodology and proportion of days covered. Serum K(+) concentrations were assessed pre- versus post-patiromer initiation. RESULTS: Study cohorts included 527 (patiromer), 852 (SPS), and 8747 (NoKb) HD patients. Median follow-up was 141 days. Patiromer initiators were 2.6 times more likely to have had multiple prior episodes of hyperkalemia (odds ratio [OR]: 2.6; 95% confidence interval [CI]: 1.8–3.7). Most (61%) commenced patiromer on 8.4 g once daily; 60% of patients’ first patiromer order remained open after 180 days. Statistically significant reductions in K(+), averaging approximately −0.5 mEq/l, were observed post-patiromer initiation (48% pre-patiromer vs. 22% post-patiromer had K(+) ≥6.0 mEq/l [P < 0.001]). CONCLUSION: Patiromer initiators receiving chronic hemodialysis had comparatively more severe, uncontrolled baseline hyperkalemia. Medication order data show long-term patiromer use was associated with significantly reduced K(+).