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

PLoS One. 2020 Jan 7;15(1):e0226844. doi: 10.1371/journal.pone.0226844. eCollection 2020.

Abstract

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.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Angiotensin-Converting Enzyme Inhibitors / adverse effects*
  • Female
  • Humans
  • Hyperkalemia / drug therapy*
  • Male
  • Patient Acceptance of Health Care
  • Polymers / therapeutic use*
  • Polystyrenes / therapeutic use*
  • Retrospective Studies
  • Sample Size
  • Socioeconomic Factors
  • United States

Substances

  • Angiotensin-Converting Enzyme Inhibitors
  • Polymers
  • Polystyrenes
  • patiromer
  • polystyrene sulfonic acid

Grants and funding

This study was funded by Relypsa, Inc., a Vifor Pharma Group Company. Relypsa, Inc., a Vifor Pharma Group Company provided support in the form of salaries for authors JF and PA and a research contract for COHRDATA (see below). JF and PA were involved in research idea and study design, data acquisition, data analysis/interpretation, and contributed to intellectual content during manuscript drafting and revisions. Aside from JF and PA, Relypsa, Inc., a Vifor Pharma Group Company did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. CGR founded COHRDATA which received a research contract from Relypsa, Inc., a Vifor Pharma Group Company. COHRDATA was involved in research idea and study design, data acquisition, data analysis/interpretation, and contributed to intellectual content during manuscript drafting and revisions. COHRDATA provided support in the form of salary for author CGR. COHRDATA received a research contract from Relypsa, Inc., a Vifor Pharma Group Company to conduct this research including the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section.