OBJECTIVES: Patients with chronic kidney disease (CKD) experience progressive decline in renal function and are at elevated risk of hyperkalemia (HK). As renal function declines, CKD patients progress to end-stage renal disease (ESRD) which is associated with significant quality of life reductions and healthcare costs. This study aimed to explore the impact of ESRD on estimated health and cost outcomes of managing HK among CKD patients.

METHODS: A lifetime patient-level simulation was developed to model CKD progression via declining estimated glomerular filtration rate (eGFR). Simulated time-dependent trajectories of serum potassium (K⁺) were linked to cardiovascular events and mortality via published rates. Published utilities and direct healthcare costs (UK, 2015) were applied from a payer perspective independent of K⁺ management and discounted at 3.5%. The impact of ESRD (eGFR<15 ml/min/1.73m) on predicted life expectancy (LE), quality-adjusted life years (QALYs) and total disease costs (TDC) was assessed for the comparison of maintained normokalaemia (NK) against fluctuating K⁺ levels, resulting in HK rates consistent with clinical practice.

RESULTS: Among CKD patients aged 60, with eGFR 50 ml/min/1.73m at baseline, estimated LE was extended by 0.6 years/patient in the NK group compared to the HK group, resulting in a greater percentage of patients reaching ESRD (49% versus 43%). Prior to patients reaching ESRD, QALYs and TDC were 5.5 and £38,050 (NK group) compared to 5.3 and £37,667 (HK group), corresponding to incremental QALYs and TDC of 0.2 and £383, respectively. Post-ESRD survival led to incremental QALYs of 0.4 (2-fold increase) and incremental TDC of £5,148 (>10-fold increase, driven by dialysis costs) in the NK group.

CONCLUSIONS: The health economic benefit of improved survival associated with NK in CKD is offset by the high costs associated with dialysis. Consequently, the long-term cost-effectiveness evaluation of effective K⁺ management in CKD is accurately described when partitioning the results by ESRD status.