OBJECTIVES: New effective but costly treatments for pemphigus, such as first-line rituximab induce an increasing demand for cost-utility analyses. In this study, we aim to elicit health utility values for pemphigus vulgaris (PV) and foliaceus (PF) health states from patients. The secondary aims are to explore predictors of utilities and to compare utility values for hypothetical health states derived from patients to results of an earlier study of similar design among members of the general population.

METHODS: Pemphigus patients were asked to evaluate three hypothetical pemphigus health states (uncontrolled PV, uncontrolled PF and controlled pemphigus) by using visual analogue scale (VAS) and composite time trade-off (TTO). A fixed 10-year timeframe was used for health states valued as better than dead, which was extended to 20 years for worse than dead health states. Predictors of utilities were analysed by multiple linear regressions.

RESULTS: Data of 108 patients (64.8% women, mean age 57.4±14.7 years) were analysed. The mean utility value for the hypothetical uncontrolled PV, uncontrolled PF and controlled pemphigus health states were 0.23±0.24, 0.39±0.23 and 0.53±0.24 with the VAS, and 0.41±0.45, 0.52±0.42 and 0.66±0.36 with the TTO. We have found older age, more severe disease expressed by Autoimmune Bullous Skin Disorder Intensity Score, longer disease duration, and the presence of visible lesions on uncovered body parts to have a significant positive impact on utilities for hypothetical health states (p<0.05). Overall, the differences in utility scores between the uncontrolled and controlled health states were lower for patients compared to members of the general population (maximum difference 0.30 vs. 0.38 in VAS and 0.25 vs. 0.40 in TTO).

CONCLUSIONS: This is the first study to assess health utilities for pemphigus health states from patients. Using utilities reflecting patient preferences in cost-utility analyses may underestimate the health gains associated with therapy.