OBJECTIVES: An increase in blood-serum-potassium levels is common in patients with renal impairment or heart failure. Lifesaving RAAS-inhibitors (RAASi) such as ACE inhibitors, AT1 receptor-antagonists and aldosterone-blockers lead to a further rise in potassium levels. Discontinuation and downtitration of RAASi result in increased morbidity, as RAASi prolong the time to complete renal insufficiency.

The purpose of this study was to extend the results of an 8-week OPAL–HK RCT for patiromer, a nonabsorbed potassium-binder, that showed significant reduction in hyperkalaemia and RAASi dose maintenance in the patiromer group (94%) compared to no-patiromer (placebo) arm (44%). The analysis was performed from the Austrian healthcare-systems perspective.

METHODS: A reported model by Sutherland et al. (2017), composed of a decision-tree and a Markov process, was used to simulate the treatment pathway of patients with chronic-kidney-disease (CKD). The short-term decision-tree estimates the proportion of CKD patients (potassium level, ≥5.0mmol/L) that continued/discontinued RAASi medication after hyperkalemia. The endpoint of the decision-tree was linked with to Markov model to simulate life-time follow-up. The model includes 6 states (stable CKD, CKD disease-progression, cardiovascular (CV) events, post CV event, hospitalization and death). The cohort definition was adopted from the OPAL–HK trial. Monte-Carlo simulation accounted for uncertainty. Direct costs and life expectancy were obtained from local sources for 2018. QALYs and costs were discounted at 5% p.a.

RESULTS: Over lifetime, costs and outcomes associated with patiromer would amount to 38,117.17€ and achieve 5.48 QALYs. Costs with no treatment are 27,157.66€ and obtain 4.90 QALYs. The results show that patiromer is associated with a significant improvement in QALYs; 7 months in perfect health. The incremental-cost-utility-ratios ICUR amounts to 18,979.23€.

CONCLUSIONS: The results indicate that treatment with patiromer vs. no-patiromer, in addition to enabling RAASi continuation, is potentially a cost-effective intervention for the treatment of hyperkalaemia in patients with CKD stages 3-4 in Austria.