Re-Treatment after Ureteroscopy and Shock Wave Lithotripsy: A Population Based Comparative Effectiveness Study

Purpose:Shock wave lithotripsy and ureteroscopy are the most commonly performed surgeries for kidney and ureteral stones, but the comparative effectiveness of these interventions at the population level is unclear. We compared re-treatment for shock wave lithotripsy and ureteroscopy.Materials and Methods:A retrospective cohort study using all-payer claims data for all patients who underwent shock wave lithotripsy or ureteroscopy from 1997 to 2016 at 74 hospitals in South Carolina was performed. The primary outcome measure was subsequent shock wave lithotripsy or ureteroscopy within 6 months of initial surgery. Pseudorandomized trials of ureteroscopy vs shock wave lithotripsy were performed for each year, applying propensity scores to balance hospital and patient characteristics. Discrete time failure models were fit using propensity score weighted logistic regression.Results:Overall 136,152 ureteroscopy and shock wave lithotripsy surgeries were performed in 95,227 unique patients with re-treatment representing 9% of all surgeries. A total of 74,251 index surgeries were shock wave lithotripsy (59.9%) and 49,743 were ureteroscopy (40.1%). Shock wave lithotripsy was associated with a 20% increased odds of re-treatment (OR 1.20; 95% CI 1.13-1.26). The probability of re-treatment was 7.5% for ureteroscopy and 10.4% for shock wave lithotripsy. Shock wave lithotripsy had the greatest risk of re-treatment at months 2 (OR 1.85; 95% CI 1.64-2.10) and 3 (OR 1.76; 95% CI 1.50-2.06). Patients with initial shock wave lithotripsy were more likely to have shock wave lithotripsy for re-treatment (84.6%) than those patients who had initial ureteroscopy were to have ureteroscopy (29.3%).Conclusions:Compared to ureteroscopy, shock wave lithotripsy was associated with increased odds of re-treatment. These results have implications for shared decision making and value based surgical treatment of nephrolithiasis.