title: The surgical management of kidney stone disease: a population based time series analysis.
abstract: OBJECTIVE
  We evaluate population based trends in the use of extracorporeal shock wave lithotripsy, ureteroscopy and percutaneous nephrolithotomy during the last 20 years, as well as assess the re-treatment rate and morbidity from treatment over time.
  
  
  METHODS
  Using administrative databases in the province of Ontario, Canada, a population based cross-sectional time series analysis was performed between July 1, 1991 and December 31, 2010. All extracorporeal shock wave lithotripsy, ureteroscopy and percutaneous nephrolithotomy procedures were identified, along with all hospital readmissions and emergency department visits within 7 days of treatment. The primary outcome was treatment use, and secondary outcomes were the need for ancillary treatment and hospital readmission or emergency department visit after treatment. Exponential smoothing and autoregressive integrated moving average (ARIMA) models were used to assess trends over time.
  
  
  RESULTS
  We identified 194,781 kidney stone treatments performed during the study period. Time series modeling revealed a significant increase in the use of ureteroscopy over time (25% to 59% of all procedures, p <0.0001) and a reciprocal decrease in the use of extracorporeal shock wave lithotripsy (69% to 34% of all procedures, p <0.0001). A corresponding significant decrease in the need for ancillary treatment over time (23% to 15%, p <0.0001) and increase in the need for hospital readmission (7% to 11%, p <0.0001) or emergency department visit (7% to 11%, p=0.0024) after treatment were also demonstrated.
  
  
  CONCLUSIONS
  Our population based study demonstrates a shift in the treatment paradigm with increased use of ureteroscopy over time and a reciprocal decrease in the use of extracorporeal shock wave lithotripsy. We also observed a corresponding decrease in ancillary treatment and increase in posttreatment morbidity over time.
authors.affiliation: Division of Urology, Department of Surgery, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada. Electronic address: Michael.ordon@utoronto.ca.
authors.forename: Michael
authors.initials: M
authors.lastname: Ordon
authors.affiliation: Division of General Surgery, Department of Surgery, University Health Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Urbach
authors.affiliation: Applied Health and Research Department, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada; Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada; Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Mamdani
authors.affiliation: Programming & Biostatistics, Institute for Clinical and Evaluative Sciences, Toronto, Ontario, Canada.
authors.forename: Refik
authors.initials: R
authors.lastname: Saskin
authors.affiliation: Division of Urology, Department of Surgery, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.
authors.forename: R John
authors.initials: RJ
authors.lastname: D'A Honey
authors.affiliation: Division of Urology, Department of Surgery, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Kenneth T
authors.initials: KT
authors.lastname: Pace
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007669:Kidney Calculi / Q000601:surgery*; D008096:Lithotripsy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009403:Nephrostomy, Percutaneous / Q000379:methods*; D009864:Ontario / Q000453:epidemiology; D011159:Population Surveillance / Q000379:methods*; D011183:Postoperative Complications / Q000453:epidemiology*; D011379:Prognosis; D012189:Retrospective Studies; D016896:Treatment Outcome; D018666:Ureteroscopy / Q000379:methods*; D055815:Young Adult
keywords: kidney calculi; lithotripsy; retreatment; ureteroscopy