OBJECTIVES

We aimed to compare mapped and derived utilities for health states among patients with ID-IBD treated with FM versus placebo. EQ-5D-mapped utilities were found in previous studies on other diseases to estimate higher utilities than those derived through SF-6D.

METHODS

Health state utilities were taken from AEGIS-1 and AEGIS-2, two trials examining FM in the treatment of IDA-IBD (ulcerative colitis and Crohn’s disease, respectively), where outcomes were measured over the first 12 weeks in a randomised double-blind trial, with a 52-week open-label extension. The SF-36 questionnaire was used to determine general quality of life. Attribution of scores to specific health states was based on haemoglobin levels collected concurrently with each assessment. With haemoglobin level (g/dL) as a surrogate for ID, the health states used were moderate (8.0-10.9), mild (11.0-12.9), and stable (>12.9) ID.

SF-36 scores were converted to EQ-5D-mapped utilities, while the same scores were used to derive SF-6D utilities using the Ara and Brazier algorithms, respectively. These scores were then compared across the different health states. A random-effect regression model was used in both algorithms to account for haemoglobin at baseline, ferritin level, and crossover in the open-label extension phase.

RESULTS CONCLUSIONS

Among patients with ID-IBD, utilities increased with haemoglobin levels, with greater increases with ferric maltol than with placebo. EQ-5D-mapped utilities were higher than SF-6D-derived utilities.