Cost-effectiveness of medical expulsive therapy using alpha-blockers for the treatment of distal ureteral stones.

OBJECTIVE

Medical expulsive therapy (MET) has recently emerged as an efficacious and safe option for the initial management of ureteral stones. The objective of this study was to assess the cost-effectiveness of MET compared with conservative therapy for the treatment of ureteral stones using international cost data from the United States and four European countries.

MATERIAL AND METHODS

A decision analysis model was built with the use of TreeAge Pro 2004 software with linear success rate assumptions. The likelihood of spontaneous passage of ureteral stones according to their size and location was estimated with the use of data derived from a published meta-analysis. The estimated cost of ureteroscopy (URS) in the United States ($4973) was based on the mean cost of 121 consecutive cases performed at a large metropolitan hospital. URS costs for other countries were obtained from a published international survey. The cost of tamsulosin ($2.08 per day), currently the most commonly used medical expulsive agent, was estimated as a mean of the costs obtained from two national pharmacy chains. MET and conservative therapies were compared with the use of one-way and two-way sensitivity analyses.

RESULTS

In the United States, MET using tamsulosin resulted in a $1132 cost advantage over observation. MET maintained its cost advantage even in countries where the cost of URS is much lower than in the United States. Two-way sensitivity analysis showed that MET remained cost-effective even with very low rates of spontaneous passage, minimal benefit of MET, or low cost of URS.

CONCLUSION

MET is a cost-effective strategy for the management of distal ureteral stones--even those with a low rate of spontaneous passage--providing another incentive for initial "facilitated observation" before embarking on surgical intervention.