Rezaee ME. et al., 2019: Regional Variation in Shock Wave Lithotripsy Utilization Among Medicare Patients with Nephrolithiasis
Rezaee ME., Tundo GN., Goodney PP., Pais VM Jr..
Section of Urology, Department of Surgery, Dartmouth-Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH.
Section of Vascular Surgery, Dartmouth-Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH; VA Outcomes Group, Veterans Health Association, VT; The Dartmouth Institute for Health Policy and Clinical Practice, One Medical Center Drive, Lebanon, NH.
Section of Urology, Department of Surgery, Dartmouth-Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH.
Abstract
OBJECTIVE: To characterize shock wave lithotripsy (SWL) utilization and assess for regional variation in the use of this procedure across the United States. MATERIALS AND METHODS: We examined SWL and URS utilization among Medicare Beneficiaries with a diagnosis of nephrolithiasis for the years 2006, 2009, and 2014. Adjusted utilization rates were calculated per 1000 beneficiaries accounting for age, sex, and race. Utilization rates were examined nationally and by hospital referral region (HRR). RESULTS: A total of 511,495, 604,493, and 806,652 Medicare beneficiaries had a diagnosis of nephrolithiasis in 2006, 2009, and 2014, respectively. The adjusted rate of SWL per 1000 beneficiaries with nephrolithiasis decreased from 59.4/1000 in 2006 to 52.2/1000 and 45.5/1000 in 2009 and 2014 (13.9% decrease, P < .001). Variation was observed in SWL utilization; up to a 12-fold difference between HRRs (9.2/1000 in Winchester, VA to 105.8/1000 in Lincoln, NE). The adjusted rate of URS per 1000 beneficiaries increased by 10.2% (P < .001) between 2006 and 2014. However, the percent decrease in SWL utilization did not correlate with the percent increase in URS utilization when examined by HRR (P = .66). CONCLUSION: Variation exists in the utilization of SWL among Medicare beneficiaries (12-fold difference). This variation is likely secondary to a series of supply, urologist, and patient-specific factors. SWL utilization decreased between 2006 and 2014, while URS increased. Stone procedure type is likely highly dependent on where patients receive their urologic care.
Urology. 2019 Nov;133:103-108. doi: 10.1016/j.urology.2019.07.024. Epub 2019 Aug 1.
Comments 1
This is an interesting report on how SWL and URS have been utilized in USA during the period 2006-2014. The 13.9 % decrease in SWL is not surprising and might reflect what happens worldwide.
The authors discuss different explanations for this change as well as the large variation in utilization of SWL within USA; from 9.2 to 105.8 per 1000 patients (beneficiaries).
To which extent the well recognized differences in stone-free rates have contributed to this result is unknown, but other factors such as availability of SWL devices, cost and patients’ preference is mentioned. In USA it is considered that SWL is more expensive or at least less cost effective than URS. But patients’ preference cannot be considered to be without influence from the treating urologist.
Whether SWL in some places is overused or underused is not decided but it is of interest to note that whereas URS increased by 10.2 %, SWL decreased by 13.9 %. Moreover, there was a remarkable variation in how URS was used; 7.9 – 63.1 /1000.
Although similar difference might occur in many countries, it is of note that only patients ≥ 65 years were included in this study.