Presentation Authors: Marc Nelson, Parth Patel*, Amanda Garza, Emanuel Eguia, Patrick Sweigert, Marshall Baker, Gopal Gupta, Ahmer Farooq, Thomas Turk, Kristin G. Baldea, Maywood, IL
Introduction: Extracorporeal shockwave lithotripsy (ESWL) and flexible ureterorenoscopy (URS) are first-line treatment options for uncomplicated nephroureterolithiasis. It is well established that stone-free rates are higher for those undergoing URS. Given the variable definitions for "stone-free", however, an analysis of retreatment rates in clinical practice is necessary to truly evaluate the effectiveness of the two modalities. Furthermore, an accurate understanding of the treatment costs is paramount in today's cost-conscious healthcare environment.
Methods: The Healthcare Cost and Utilization Project State Ambulatory Surgery Database for Florida from 2010-2015 was utilized. CPT codes were used to identify patients who underwent initial ESWL or URS. Patients were tracked longitudinally for subsequent stone surgeries within 90 days. Costs of care were estimated from reported charges by applying hospital-specific cost to charge ratios. Descriptive analyses were performed. A multivariable logistic regression model was utilized to determine predictors of a second stone operation within 90 days.
Results: 98,011 patients underwent initial ESWL or URS. 21.2% of those who underwent initial ESWL had a second stone surgery within 90 days, vs. 10.1% of patients who underwent initial URS (p < 0.005) (Table 1) On multivariate analysis, initial ESWL results in a more than 2-fold increased odds of a second procedure within 90 days compared to initial URS (OR 2.40, p < 0.005). Older patients had an increased odds risk of undergoing a second surgery (Age 50-70 OR 1.46, p < 0.005) while Black race (OR 0.92, p=0.032) Hispanic race (OR 0.83, p < 0.005) and those with higher comorbidity scores (CCI>=3 OR 0.68, p < 0.005) had decreased odds of second surgery. The per-patient 90 day cost was $6239 for initial ESWL and $5319 for initial URS (p < 0.005).
Conclusions: ESWL results in higher retreatment rates and is more costly than URS. Further comparison studies should be performed to confirm these findings.