Cost-effectiveness of urethral bulking polydimethylsiloxane-Urolastic® compared with mid-urethral sling surgery for stress urinary incontinence: A two-arm cohort study

Objective: To investigate the cost-effectiveness of urethral bulking polydimethylsiloxane-Urolastic® (PDMS-U) compared with mid-urethral sling (MUS) surgery for stress urinary incontinence (SUI) at 1-year follow-up.

Design: Prospective, two-arm cohort study with 2-year follow-up.

Setting: International multicentre.

Population: Women with moderate to severe SUI.

Main outcome measures: Primary outcome was subjective cure (Patient Global Impression of Improvement).

Secondary outcomes: objective cure (negative cough stress test), Urogenital Distress Inventory (UDI-6), complications and re-interventions. Cost-effectiveness outcomes: total costs, quality-adjusted life year (QALY) using IIQ7-scores (Incontinence Impact Questionnaire) and EQ-5D-5L, incremental cost-effectiveness ratio (ICER) and monetary benefit (adjusted for baseline confounders).

Results: In all, 131 PDMS-U and 153 MUS surgery patients were treated. Subjective cure rates for MUS surgery and PDMS-U were, respectively: 101/112 (90%) versus 40/87 (46%), adjusted odds ratio (aOR; for age, body mass index [BMI], severity, type of urinary incontinence and previous SUI procedure) was 4.9. Objective cure rates for MUS surgery and PDMS-U were respectively: 98/109 (90%) versus 58/92 (63%), aOR 5.4. Average total costs for PDMS-U and MUS surgery were €3567 and €6688. ICER for MUS surgery cost €15 598 per IIQ QALY and €37 408 per EQ-5D-5L QALY. With a willingness to pay (WTP) of €25 000, MUS has a 84% chance of being cost-effective using IIQ, whereas PDMS-U has a 99% chance of being cost-effective using EQ-5D-5L.

Conclusion: MUS surgery is more cost-effective in realising improved disease-specific quality of life (QoL), while PDMS-U is more cost-effective in realising improved generic QoL.