Trends in Regionalization of Care and Mortality For Patients Treated With Radical Cystectomy.

BACKGROUND

Regionalization to higher volume centers has been proposed as a mechanism to improve short-term outcomes following complex surgery.

OBJECTIVE

The objective of this study was to assess trends in regionalization and mortality for patients undergoing radical cystectomy (RC).

RESEARCH DESIGN

An observational study of patients receiving RC in the United States from 2004 to 2013.

SUBJECTS

Data for patients receiving RC were extracted from the National Cancer Database.

MEASURES

The primary exposure was hospital volume; low-volume hospitals (LVH) included those with <5 RC/year and high-volume hospitals (HVH) were those with ≥30 RC/year. Trends in the volume were assessed, as were 30- and 90-day mortality. Cochrane-Armitage tests were performed for volume, and propensity score-weighted proportional hazard regression was used to assess mortality.

RESULTS

A total of 47,028 RC were performed in 1162 hospitals from 2004 to 2013. The proportion of RC at LVH declined from 29% to 17% (P<0.01), whereas that of HVH increased from 16% to 33% (P<0.01). Unadjusted 30- (P=0.02) and 90-day (P<0.001) mortality decreased, and the absolute decrease was greatest at LVH (4.8% vs. 2.6%, P=0.03), whereas rates for HVH remained stable (1.9% vs. 1.4%, P=0.34). Following risk-adjustment, relative to treatment at HVH, treatment at LVH was associated with increased 30-day (hazard ratio: 1.66, 95% CI: 1.53-1.80) and 90-day mortality (hazard ratio: 1.37, 95% confidence interval: 1.30-1.44).

CONCLUSIONS

Regionalization of RC to HVH was observed from 2004 to 2013. Treatment at LVH was associated with 66% and 33% relative increases in hazard of death at 30 and 90 days, respectively. These findings support the selective referral of complex cases to higher volume centers.