Cost-effectiveness of urolithiasis management in pregnancy

Introduction: Urolithiasis complicating pregnancy presents a challenge for urology and obstetric teams. The management options of ureteral stenting, percutaneous nephrostomy and ureteroscopy vary significantly with regard to efficacy, complications, impact on quality of life and costs. This analytic model compares these factors to determine an optimal strategy per gestational age at presentation. Methods: A decision analytic model was built that compared stenting, percutaneous nephrostomy and ureteroscopy. Outcomes included treatment failure, need for re-treatment and complications stratified by severity. Probabilities and utilities were derived from the literature and costs were derived from institutional charge data. The time horizon was 1 year with disutilities limited to gestation length or recovery time for treatment or complication. Multivariate sensitivity analyses and Monte Carlo analysis were performed to evaluate model robustness. Results: In a simulated cohort of 1,000 pregnant women with urolithiasis ureteroscopy would yield 960 quality adjusted life years, compared to 870 with stenting and 880 with percutaneous nephrostomy. Treatment via stenting or percutaneous nephrostomy would fail more than twice as often as ureteroscopy and more than half of patients would require subsequent definitive management. In this cohort ureteroscopy would save $38.8 million compared to stenting and $17.6 million compared to percutaneous nephrostomy. Given its lower costs and improved outcomes, ureteroscopy was the dominant strategy across all gestational ages and remained dominant in all sensitivity analyses and Monte Carlo simulations. Conclusions: Regardless of gestational age, ureteroscopy was a cost-effective strategy to manage urolithiasis compared to stenting or percutaneous nephrostomy. This result was robust against substantial changes in model parameters.