PD15-04 EXTRACORPOREAL SHOCK WAVE LITHOTRIPSY HOSPITAL READMISSION CAUSES AND TRENDS

Abstract

INTRODUCTION AND OBJECTIVE: Extracorporeal shockwave lithotripsy (ESWL) is a noninvasive and generally safe procedure used to treat renal and ureteral stones. Previous retrospective series have estimated 90-day readmission rates around 10%. We aimed to better characterize real-world readmission causes and trends using a large statewide database. METHODS: We performed a population-based cohort study using the New York Statewide Planning and Research Cooperative System (SPARCS) database. Using ICD-9 diagnosis and procedure codes, patients who underwent ESWL between 2004-2013 were identified and tracked for 30- and 90-day readmissions. Readmission diagnoses were classified, and rates were tracked over time. Stone characteristics are not available in SPARCS. A multivariable logistic regression was performed using patient age, sex, race, and insurance status to identify factors related to early readmission. RESULTS: 81,425 ESWL cases were obtained for analysis in the 10-year study window. The overall 30-day readmission rate was 6.1% (N=4994) and 90-day readmission rate was 11.3% (N=9226). The number of cases per year remained stable (range 7233 to 9068) as did the readmission rate (range 9.7% to 12.1%). Urological complaints were the most common causes for readmissions accounting for 67.1% (N=3349) of all 30-day readmissions and 56.7% (N=5235) of all 90-day readmissions. The most common urological causes for 30/90-day readmissions were nephrolithiasis (48.2%/40.5%), infection (12.4%/10.9%), stent problems (2.7%/2.2%), and bleeding (1.7%/1.4%). The most common non-urologic causes were cardiac events (6.3%/7.2%) and GI complications (4.4%/5.0%). Logistic regression showed increased odds of 30-day readmission for women (OR 1.13, 95% CI 1.07-1.20, p<0.001), patients with advanced age (61-80 years OR 2.00, 95% CI 1.45-2.78, p<0.001 and 81+ years OR 2.64, 95% CI 1.86-3.75, p<0.001) and those with Medicare (OR 1.32, 95% CI 1.20-1.44, p<0.001) or Medicaid (OR 2.11, 95% CI, 1.88-2.37, p<0.001). CONCLUSIONS: Readmission after ESWL occurred in 6.1% of patients at 30-days and 11.3% at 90-days. The majority of diagnoses driving readmission were urological related to nephrolithiasis. Other commonly cited risks like infection and bleeding remain relatively rare events. These data can help physicians better counsel their patients on the risks of ESWL and evaluate their own outcomes relative to a real-world patient cohort. Source of Funding: None