Cost-of-illness analysis of ulcerative colitis patients treated with biological therapy: a prospective observational study in Iran

Abstract

Abstract Background No research has assessed the comprehensive annual costs of managing ulcerative colitis (UC) patients undergoing biological treatment. This study aimed to determine the annual costs and primary cost drivers for UC patients receiving biological therapy. Methods This prospective observational study was conducted in Iran from a societal perspective, employing the cost-of-illness method, grounded in human capital theory. A prevalence-based approach and bottom-up technique were used for cost estimation. Inpatient costs were extracted from hospital records, while outpatient service usage and direct non-medical costs over a one-year follow-up were collected through patient interviews. Indirect costs were evaluated using a standardized questionnaire. The average costs per patient were calculated, and the factors affecting patient expenses were analyzed using the Mann-Whitney and Kruskal-Wallis statistical tests. Results The study included 238 UC patients (50.8% male; mean age: 37.66 ± 12.13 years), with 32.8% receiving Infliximab (IFX) and 67.2% on Adalimumab (ADA), and an average disease duration of 9.29 ± 6.5 years. The total annual economic burden per UC patient was USD 2316.90. Of this, direct medical costs constituted 49.84%, direct non-medical costs 21.13%, and indirect costs 29.03%. Notably, higher expenses were significantly associated with patients under 20 years of age and those treated with ADA. Conclusions Biological therapies accounted for the largest share of direct medical expenses, while productivity losses, mainly resulting from temporary absenteeism, were identified as a major factor contributing to the economic burden of UC in Iran.

Keywords

• Ulcerative colitis
• Cost of illness
• Economic burden
• Direct costs
• Indirect costs