To compare the cost-effectiveness of 3 midurethral sling (MUS) utilization strategies in preventing occult stress urinary incontinence (SUI) 1-year following vaginal prolapse repair (VPR).

We created a decision analysis model to compare 3 approaches: 1) Staged: VPR alone without MUS, 2) Universal sling: VPR with concomitant MUS, and 3) Preop CST: VPR with selective concomitant MUS based on preoperative cough stress test at a bladder volume of at least 300 ml (see Figure). All MUS were assumed to be retropubic in this model. Using high quality literature, we modeled risks of occult SUI, sling failure, false negative CST, reoperation for urinary retention or mesh complication, and treatment for overactive bladder (OAB). We estimated costs using the United States Medicare 2020 reimbursement rates in dollars. The main outcome was incremental cost-effectiveness ratio (ICER). A commonly used ICER threshold of less than $50,000 per quality-adjusted life year (QALY) was considered cost-effective in this study. One-way sensitivity analyses were performed to assess for model robustness.

All base case assumptions can be found in the Table. Pre-op CST was less costly per QALY than Universal sling with an ICER of $2,664 versus $7,766/QALY. With an increasing share of women (>61.8%) with occult SUI electing to undergo MUS, Universal sling would then replace Pre-op CST to be the more cost-saving strategy. Multiple 1-way sensitivity analyses showed no other meaningful thresholds, including varying rates of sling lysis, mesh exposure requiring excision, treatment for OAB, false negative CST, and costs of CST. 

A surgeon switching from a Staged to a Pre-op CST approach would need to perform 22 Pre-op CST cases to prevent one patient from returning to the operating room for a MUS. Conversely, a surgeon changing from a Pre-op CST to a Staged approach would need to perform: 39 Staged cases to prevent one patient from taking OAB medications, 61 Staged cases to prevent one patient from returning to the operating room for sling lysis due to voiding dysfunction, and 156 Staged cases to prevent one patient from returning to the operating room for mesh excision due to an exposure.

Compared to a Staged approach, both Pre-op CST and Universal sling were cost effective during the 1-year following VPR. Of the two approaches, Pre-op CST was more cost-effective. However, Universal sling becomes more cost-effective when more women choose to undergo MUS for occult SUI after VPR. This model was robust to sensitivity analyses. 

The low number of prophylactic MUS procedures required to prevent one reoperation for occult SUI in a Staged approach supports the view that prophylactic MUS is effective. On the other hand, the two- to seven-fold higher numbers of Staged procedures needed to prevent one reoperation due to prophylactic MUS complications further demonstrate that the Staged approach should be subject to shared decision-making with the patients.

Pre-op CST is the more cost-effective strategy to prevent occult SUI than Universal sling in women undergoing vaginal prolapse surgeries. Women should be carefully counseled regarding the possibility of occult SUI as well as the benefits and risks of prophylactic MUS surgery at time of vaginal prolapse surgeries.