Cost-effectiveness analysis of adjunct VSL#3 therapy versus standard medical therapy in pediatric ulcerative colitis.

BACKGROUND: Inflammatory bowel diseases (IBDs) are costly chronic gastrointestinal diseases, with pediatric IBD representing increased costs per patient compared to adult disease. Health care expenditures for ulcerative colitis (UC) are >$2 billion annually. It is not clear whether the addition of VSL#3 to standard medical therapy in UC induction and maintenance of remission is a cost-effective strategy.

PATIENTS AND METHODS: We performed a systematic review of the literature and created a Markov model simulating a cohort of 10-year-old patients with severe UC, studying them until 100 years of age or death. We compared 2 strategies: standard medical therapy versus medical therapy + VSL#3. For both strategies, we assumed that patients progressed through escalating therapies--mesalamine, azathioprine, and infliximab--before receiving a colectomy + ileal pouch anal anastamosis (IPAA) if the 3 medical therapy options were exhausted. The primary outcome measure was the incremental cost-effectiveness ratio (ICER), defined as the difference of costs between strategies for each quality-adjusted life-year (QALY) gained. One-way sensitivity analyses were performed on variables to determine the key variables affecting cost-effectiveness.

RESULTS: Standard medical care accrued a lifetime cost of $203,317 per patient, compared to $212,582 per patient for medical therapy + VSL#3. Lifetime QALYs gained was comparable for standard medical therapy and medical therapy + VSL#3 at 24.93 versus 25.05, respectively. Using the definition of ICER <50,000/QALY as a cost-effective intervention, medical therapy + VSL#3 produced an ICER of $79,910 per QALY gained, making this strategy cost-ineffective. Sensitivity analyses showed that 4 key parameters could affect the cost-effectiveness of the 2 strategies: cost of colectomy + IPAA, maintenance cost after surgery, probability of developing pouchitis after surgery, and the quality of life after a colectomy + IPAA. High surgical and postsurgical costs, a high probability of developing pouchitis, and a low quality of life after a colectomy + IPAA could make adjunct VSL#3 use a cost-effective strategy.

CONCLUSIONS: Given present data, adjunct VSL#3 use for pediatric UC induction and maintenance of remission is not cost-effective, although several key parameters could make this strategy cost-effective. The quality of life after an IPAA is the single most important variable predicting whether this procedure benefits patients over escalating standard medical therapy.