Discharge dispositions, complications, and costs of hospitalization in spinal cord tumor surgery: analysis of data from the United States Nationwide Inpatient Sample, 2003-2010

Abstract

Object: The aim of this study was to analyze the incidence of adverse outcomes and inpatient mortality following resection of intramedullary spinal cord tumors by using the US Nationwide Inpatient Sample (NIS) database. The overall complication rate, length of the hospital stay, and the total cost of hospitalization were also analyzed from the database.

Methods: This is a retrospective cohort study conducted using the NIS data from 2003 to 2010. Various patient-related (demographic categories, complications, comorbidities, and median household income) and hospital-related variables (number of beds, high/low case volume, rural/urban location, region, ownership, and teaching status) were analyzed from the database. The adverse discharge disposition, in-hospital mortality, and the higher cost of hospitalization were taken as the dependent variables.

Results: A total of 15,545 admissions were identified from the NIS database. The mean patient age was 44.84 ± 19.49 years (mean ± SD), and 7938 (52%) of the patients were male. Regarding discharge disposition, 64.1% (n = 9917) of the patients were discharged to home or self-care, and the overall in-hospital mortality rate was 0.46% (n = 71). The mean total charges for hospitalization increased from $45,452.24 in 2003 to $76,698.96 in 2010. Elderly patients, female sex, black race, and lower income based on ZIP code were the independent predictors of other than routine (OTR) disposition (p < 0.001). Private insurance showed a protective effect against OTR disposition. Patients with a higher comorbidity index (OR 1.908, 95% CI 1.733-2.101; p < 0.001) and with complications (OR 2.214, 95% CI 1.768-2.772; p < 0.001) were more likely to have an adverse discharge disposition. Hospitals with a larger number of beds and those in the Northeast region were independent predictors of the OTR discharge disposition (p < 0.001). Admissions on weekends and nonelective admission had significant influence on the disposition (p < 0.001). Weekend and nonelective admissions were found to be independent predictors of inpatient mortality and the higher cost incurred to the hospitals (p < 0.001). High-volume and large hospitals, West region, and teaching hospitals were also the predictors of higher cost incurred to the hospitals (p < 0.001). The following variables (young patients, higher median household income, nonprivate insurance, presence of complications, and a higher comorbidity index) were significantly correlated with higher hospital charges (p < 0.001), whereas the variables young patients, nonprivate insurance, higher median household income, and higher comorbidity index independently predicted for inpatient mortality (p < 0.001).

Conclusions: The independent predictors of adverse discharge disposition were as follows: elderly patients, female sex, black race, lower median household income, nonprivate insurance, higher comorbidity index, presence of complications, larger hospital size, Northeast region, and weekend and nonelective admissions. The predictors of higher cost incurred to the hospitals were as follows: young patients, higher median household income, nonprivate insurance, presence of complications, higher comorbidity index, hospitals with high volume and a large number of beds, West region, teaching hospitals, and weekend and nonelective admissions.