Cost-effectiveness analysis of continuous versus intermittent renal replacement therapy for critically ill acute kidney injury patients under the perspective of the Brazilian Private Healthcare System

Abstract

Objective: The objective of this study is to compare the costs and outcomes of Continuous Renal Replacement Therapy (CRRT) versus Intermittent Hemodialysis (IRRT) in patients with acute kidney injury from the perspective of the private healthcare system in Brazil. Methods: An analytical decision model was developed based on the clinical results found in the Ethgen et al., 2015 study. Our study followed the CHEERS (Consolidated Health Economic Evaluation Reporting Standards) to report economic valuation. When acute kidney injury occurs in the ICU, patients are initiated in CRRT or IRRT. It was assumed that the length of hospital stay and ICU are the same for both modalities. The model assumes that once patients become dialysis dependent they do not recover their kidney function and remain on dialysis or die. The study horizon was 1 year, 5 years (base-case) and 20 years. Only direct costs to the private system were considered. The clinical outcomes (utilities) are from the Klarenbach & Manns, 2009 study. According to the Brazilian guidelines for health technology assessment, costs and outcomes were discounted at a rate of 5% per year with a sensitivity analysis in the range of 0% to 10% per year. In addition, two sensitivity analyzes were performed: a one-way, which generated a tornado diagram, and a two-way deterministic one considering the two key parameters that differentiate CRRT from IRRT: the daily implementation cost difference and the cumulative risk of dialysis dependence. We ran both analyzes with the time horizon of 1 year, 5 years and lifetime. According to local practices, we used the threshold of 3 times per capita GDP, that is, R $ 84,741 (3 x R$ 28,247) as the threshold for cost-effectiveness. Results: When we compare CRRT to IRRT for the initial treatment of acute kidney injury, CRRT is dominant vs. IRRT from 18 months of treatment. Based our assumptions, the cohort of patients initially treated with CRRT had better clinical outcomes (QALYs – Quality Adjusted Life Year) and lower total costs of treatment. Patients treated with CRRT are more likely to recover renal function. Conclusion: The results suggest that CRRT when compared to IRRT can be considered a dominant therapy, that is, it offers better outcomes and lower total treatment costs, under the perspective of the private healthcare system in Brazil.