Estimating health state utilities in primary hyperoxaluria type 1: a valuation study

Quantitative data on health state utilities in primary hyperoxaluria type 1 (PH1) are lacking. This study was conducted to estimate utility values in PH1 using 3 standard valuation techniques.

Health state vignettes were developed with input from expert clinicians to describe different stages of chronic kidney disease (CKD) within the setting of PH1, along with a post-combined liver and kidney transplant (CLKT) health state ≥12 months following transplantation. The utility associated with living in each PH1 health state, as described by the vignettes, was evaluated by members of the UK general public using standard utility assessment techniques, including EQ-5D-5L, Visual Analog Scale, and Time Trade-Off.

A similar pattern across the three valuation methods was observed. Utility values were roughly constant from CKD stage 1-3b and then dropped sharply from these states to CKD stage 4. Decreases in utility in the later stages of CKD (stages 4-5) were followed by a recovery in quality of life in the post-CLKT health state.

Vignettes may not fully capture the burden of living with PH1.

This study serves as an informative source of data on how the burden of PH1 varies across disease stages of CKD and post-CLKT in patients with PH1. The study findings highlight the unique clinical features of PH1 compared with non-PH1-related CKD, such as the need for earlier and more intensive hemodialysis, the risk of systemic oxalosis, and the potential need for CLKT (as opposed to kidney-only transplant). The impact of PH1 on health-related quality of life, which worsens once hemodialysis is required and systemic disease manifestations occur, is captured in this study using quantitative health state utilities. These data provide an understanding of the impact of PH1 on health-related quality of life and will facilitate health economic evaluation of future treatments.