1440. Trends in Rural and Urban Spine Practice in the United States: Safety and Cost Profiles of Patients After Lumbar Fusion

Authors: Hansen Deng; John Yue, MD; Pavan Upadhyayula; Dean Chou, MD (Long Beach, CA)

Introduction: Patients in rural regions are more likely to experience medical problems and lack services. An improved understanding of safety and cost between rural and urban spine practices is needed. Here, we identify differences in complication, mortality, and cost profiles of patients undergoing elective lumbar fusion for degenerative disease at rural/urban centers, and evaluate their relationship to patient outcomes. Methods: Data were extracted from National Inpatient Sample 2002-2014. Patient characteristics and eleven complication categories (anemia, hardware, infection, hematoma/seroma, neurological, puncture, thromboembolic, cardiac, pulmonary, gastrointestinal, and renal/urinary) were reviewed, along with mortality, cost, and hospitalization length. Odds ratio(OR) and 95% confidence intervals[95% CI] are reported. Significance was assessed at p<0.001 for multiple comparisons. Results: There were 278,144 adult admissions (urban:267705, rural:11519). Age was 56.8±14.2, 56% patients were female. Eighty-nine percent underwent 1-2 level fusion, 10% had 3-7 level fusion, and 1% had ≥8 level fusion. A higher proportion of 3-7 level fusion was performed at urban centers(10.3% vs. 8.2%,p<0.001). Posterior approach was more utilized in rural settings(54%-rural vs. 50%-urban,p<0.001) whereas more combined approach was done at urban centers(11%-rural vs. 15%-urban,p<0.001). Inflation-adjusted cost was $33178±19535, with higher cost in rural regions($38046±24421-rural vs. $32969±19270-urban,p<0.001). Nineteen-percent experienced complications and there were 223 deaths. Common complications were anemia(11.3%), renal/urinary(1.9%) and pulmonary(1.8%). On multivariate analysis, greater fusion level(3-7 level: OR1.6[1.6,1.7],p<0.001;≥8 level: OR2.2[1.9,2.5],p<0.001)and posterior approaches(OR1.2[1.2,1.3],p<0.001) had increased complication odds, while combined approach associated with lower complication(OR0.7[0.6,0.7],p<0.001). Rural/urban setting did not associate with complication or mortality. Conclusion: Lumbar fusion is a safe surgery with no differences in complication and mortality between rural and urban centers. Posterior approach was more utilized in rural setting, whereas urban centers performed greater multilevel fusion and combined approach with lower hospital service cost. These findings are attributable in part to differences in volume, surgeon availability and preference, and hospital overhead charge.