LAUSR

OBJECTIVE The prevalence of obesity continues to rise in the United States at a disparaging rate. While previous studies have attempted to identify the influence obesity has on short-term outcomes following elective spine surgery, few studies have assessed the impact on Discharge Disposition following anterior cervical discectomy and fusion (ACDF) for cervical spondylotic myelopathy (CSM). The aim of this study was to determine whether obesity impacts the hospital management, cost, and discharge disposition after elective ACDF for adult CSM. METHODS The National Inpatient Sample (NIS) database was queried using the International Classification of Diseases, 10th revision, Clinical Modification Coding system to identify all (≥18 years) patients with a primary diagnosis of CSM undergoing an elective ACDF for years 2016 and 2017. Discharge weights were used to estimate national demographics, Elixhauser comorbidities, complications, length of stay (LOS), total cost of admission, and discharge disposition. RESULTS There were 17,385 patients included in the study, of which 3,035 (17.4%) had obesity (Non-Obese: 14,350; Obese: 3,035). The obesity cohort had a significantly greater proportion of patients with 3 or more comorbidities compared to the non-obese cohort (Non-Obese: 28.1% vs. Obese: 43.5%, p<0.001). The overall complication rates were higher in the obesity cohort (Non- Obese: 10.3% vs. Obese: 14.3%, p=0.003). On average, the obesity cohort incurred a total cost of admission $1,154 greater than the cost of the non-obese cohort (Non-Obese: $19,732 ± 11,605 vs. Obese: $20,886 ± 10,883, p=0.034) and a significantly greater proportion of non-routine discharges (Non-Obese: 16.6% vs. Obese: 24.2%, p<0.001). In multivariate regression analysis, obesity, age, race, healthcare coverage, hospital bed size, region, comorbidity and complication rates all were independently associated with non-routine discharge disposition. CONCLUSIONS Our study demonstrates that obesity is an independent predictor for non-routine discharge disposition following elective anterior cervical discectomy and fusion for cervical spondylotic myelopathy.