Health-Related Utility Weights in a Cohort of Real-World Crohn's Disease Patients

Abstract

Background and aims: Estimating health-related utility weights in Crohn's Disease [CD] patients is crucial for assessing the cost-effectiveness of new pharmaceutical interventions. Values used in most analyses are based on secondary data and vary substantially among studies. We estimated utility weights in a consecutive sample of real-world CD patients.

Methods: Patients enrolled in an ongoing socioeconomic study of CD in the Israeli adult patient population completed a self-administered Short Form 36 health survey [SF-36] and Short Inflammatory Bowel Disease [SIBDQ] questionnaires and were assessed for their current clinical status, including the Harvey-Bradshaw Index [HBI] of disease severity. For each patient enrolled we calculated a utility weight using the SF-6D scoring system.

Results: The cohort comprised 425 patients [40% male] with mean age of 39.1 [± 14.0] years. The average HBI was 6.1 [± 5.4]; 198 [47%] patients were in remission state [HBI < 5], 99 [23%] had mild disease [HBI 5-7], 102 [25%] moderate [HBI 8-16], and 26 [6%] severe disease [HBI > 16]. Mean utility weights were: 0.667 in all patients, 0.744 in patients with disease remission, 0.638 in mild disease, 0.587 in moderate disease, and 0.505 in severe disease. The significant predictors of utility weights in a multivariable regression analysis were the HBI [β = -0.494; p < 0.001], economic status [β = 0.198; p < 0.001], time since diagnosis [β = 0.106; p < 0.001], male [compared with female] gender [β = 0.099; p = 0.009], hospital admission in the past year for any cause [β = -0.086; p = 0.027], and treatment with steroids [β = -0.100; p = 0.012] where β denotes the standardised regression coefficients; model adjusted R(2) = 0.428.

Conclusions: Utility weights for patients in the remission and mild disease states were generally lower as compared with values used in published cost-effectiveness analyses. These values should be considered when assessing the value for money of future interventions for CD.