Purpose: We determined the cost-effectiveness of sacral neuromodulation vs intravesical botulinum toxin A for the treatment of refractory urge incontinence.
Materials and methods: We developed a Markov decision model using a societal perspective to compare costs (2008 U.S. dollars) and effectiveness (quality adjusted life-years) of sacral nerve stimulation and botulinum toxin A. Our primary outcome was the incremental cost-effectiveness ratio, which was defined as (sacral nerve stimulation cost - botulinum toxin A cost)/(sacral nerve stimulation quality adjusted life-year - botulinum toxin A quality adjusted life-year). Sensitivity analyses were performed to assess the impact of varying efficacy, costs and adverse event rates over the range of reported values.
Results: In the base case scenario sacral nerve stimulation was more expensive ($15,743 vs $4,392) and more effective (1.73 vs 1.63 quality adjusted life-years) than botulinum toxin A during a 2-year period. The incremental cost-effectiveness ratio was $116,427 per quality adjusted life-year. Using conventional incremental cost-effectiveness ratio thresholds of $50,000 and $100,000 per quality adjusted life-year, sacral nerve stimulation was not cost-effective. In sensitivity analyses intravesical botulinum generally remained cost-effective.
Conclusions: During a 2-year period botulinum toxin A was cost-effective compared to sacral neuromodulation for the treatment of refractory urge incontinence. Additional data regarding time to failure after botulinum toxin A injections, long-term efficacy with repeat botulinum toxin A injections and long-term complications with both therapies will be helpful for future cost-effectiveness studies.