Hyperkalemia treatment modalities: A descriptive observational study focused on medication and healthcare resource utilization.

Renin-angiotensin-aldosterone system inhibitor (RAASi) therapy has been shown to improve outcomes among patients with congestive heart failure, diabetes, or renal dysfunction. These patients are also at risk for the development of hyperkalemia (HK), often leading to down-titration and/or discontinuation of RAASi therapy. Patiromer is the first sodium-free, non-absorbed potassium (K+) binder approved for the treatment of hyperkalemia (HK) in over 50 years. We described the association between use of K+ binders (Patiromer and sodium polystyrene sulfonate [SPS]) and renin-angiotensin-aldosterone system inhibitor (RAASi), on healthcare resource utilization (HRU). The study population consisted of Medicare Advantage patients with HK (K+ ≥ 5.0 mmol/L) in Optum's Clinformatics® Data Mart between 1/1/2016-12/31/2017. Patiromer and (SPS) initiators, and HK patients not exposed to a K+ binder (NoKb) were included. The index date was the date of the first K+ binder dispensing or HK diagnosis. Outcomes assessed at 6 months post-index were: (1) K+ binder utilization, (2) RAASi continuation, and (3) HRU (pre- vs post-index). HRU change was analyzed using McNemar's statistical test. Study cohorts included 610 (patiromer), 5556 (SPS), and 21,282 (NoKb) patients. Overall baseline patient characteristics were: mean age 75 years; female 49%, low-income subsidy 29%, chronic kidney disease 48% (63% for patiromer cohort), and congestive heart failure 29%. At 6 months post-index, 28% (patiromer) and 2% (SPS) remained continuously exposed to the index K+ binder. RAASi continued for 78% (patiromer), 57% (SPS), and 57% (NoKb). The difference (pre- vs post-index) in hospitalized patients was: -9.4% (patiromer; P<0.05), -7.2% (SPS), and +16.8% (NoKb; P<0.001). Disparate K+ binder utilization patterns were observed. The majority of patiromer patients continued RAASi therapy while the percentage of SPS patients that continued RAASi therapy was lower, overlapping CIs were observed. Following continuous patiromer exposure, statistically significant reductions in hospital admissions and emergency department visits were observed, continuous SPS exposure observed no statistically significant reductions in either hospitalizations or ED visits, while NoKb patients with continuous exposure had statistically significant increases in both. Further research, with a larger sample size using comparative analytic methods, is warranted

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+. Keywords: hemodialysis, hyperkalemia, patirome