Ordon M et al, 2014: The Surgical Management of Kidney Stone Disease: A Population-Based Time Series Analysis.
Ordon M, Urbach D, Mamdani M, Saskin R, D'A Honey RJ, Pace KT
Division of Urology, Department of Surgery, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.
Division of General Surgery, Department of Surgery, University Health Network, University of Toronto, Toronto, Ontario, Canada.
Applied Health and Research Department, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.
Programming & Biostatistics, Institute for Clinical and Evaluative Sciences, Toronto, Ontario, Canada.
Division of Urology, Department of Surgery, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.
Abstract
PURPOSE: To evaluate population-based trends in the use of extracorporeal shockwave lithotripsy (SWL), ureteroscopy (URS) and percutaneous
nephrolithotomy (PCNL) over the past 20 years, as well as assessing retreatment 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-December 31, 2010. All SWL, URS and PCNL procedures were identified, along with all hospital readmissions and emergency department (ED) visits within 7 days of treatment. The primary outcome was treatment utilization and the secondary outcomes were the need for ancillary treatment and hospital readmission or ED visit post-treatment. Exponential smoothing and autoregressive integrated moving average models were utilized to assess trends over time. RESULTS: We identified 194,781 kidney stone treatments performed during the study period. Time series modeling demonstrated a significant increase in the utilization of URS over time (25% to 59% of all procedures, p<0.0001) and a reciprocal decrease in the utilization of SWL (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 ED visit (7% to 11%, p=0.0024) post-treatment was also demonstrated. CONCLUSIONS: Our population-based study demonstrates a shift in the treatment paradigm with increased use of URS over time and a reciprocal decrease in SWL utilization. We also observed a corresponding decrease in ancillary treatment and increase in post-treatment morbidity over time.
J Urol. 2014 May 24. pii: S0022-5347(14)03688-X. doi: 10.1016/j.juro.2014.05.095. [Epub ahead of print]
Comments 1
This is a very important publication as it demonstrates - at least for a certain geographic area - what kind of stone treatment urologists prefer.
Primary outcomes were trends in utilization of SWL, URS and PCNL over time. Secondary Outcomes were trends in the need for ancillary treatment and morbidity. Morbidity was measured by hospital readmissions and ED visits within 7 days of primary hospital discharge.
Morbidity due to double-J-stenting was not taken into account and stent removal – being an outpatient procedure - was not counted as an ancillary procedure.
A consistently higher proportion of patients were readmitted or return to the ED following URS compared to SWL.
I liked the concluding remarks in the discussion section, because they guide the reader to the problems adherent with the study:
“Unfortunately, secondary to the observational nature of this study we cannot infer a causal association between the contemporaneously associated changes in treatment utilization and decreasing ancillary treatment and increasing hospital readmission and ED visit rate. Rather, these trends, associated in time, are hypothesis generating and require more rigorous evaluation in future studies. An important next step is to perform a cost-effectiveness analysis of SWL versus URS to determine whether the decrease in ancillary treatment associated with the increased use of URS outweighs the increase in post-procedure morbidity.”