8. Factors contributing to cost in management of spinal epidural abscesses

Abstract

<h3>BACKGROUND CONTEXT</h3> Spinal epidural abscesses (SEA) are increasing in incidence and may be associated with high rates of morbidity and mortality. While management classically consisted of urgent surgical decompression, advances in diagnostic imaging and antibiotic therapies have made possible earlier diagnosis and nonoperative management. Previous work examining the cost of surgically managed SEA demonstrates that this clinical entity is both expensive and associated with high mortality rates. <h3>PURPOSE</h3> To compare costs between operatively and nonoperatively managed spinal epidural abscesses. <h3>STUDY DESIGN/SETTING</h3> Retrospective cohort study at 2 tertiary academic centers. <h3>PATIENT SAMPLE</h3> Adult patients receiving treatment for spinal epidural abscesses (2016-2017). <h3>OUTCOME MEASURES</h3> Cumulative charges at index hospital discharge, and at 90-days and one-year following discharge. <h3>METHODS</h3> Medical records, laboratory results and hospital billing data were reviewed for data abstraction. Demographic factors including age, sex, region of abscess, intravenous drug use, and comorbidities were abstracted, along with clinical factors such as symptoms and ambulatory function at presentation, spinal instability, ICU admission and complications. The primary outcome was total charges of initial admission, with charges for admission and care delivered in the first 90 days, and total 1-year charges (with only related charges recorded between 90-days and 1-year) considered secondarily. All covariates abstracted were included in this exploratory analysis using negative binomial regression that accounted for confounders and the nonparametric nature of cost data. Results are presented as an incidence rate ratio (IRR) with 95% confidence intervals (CI). <h3>RESULTS</h3> Sixty-six patients were included with mean age 56.6 (SD 16.2). The majority of patients (57.2%) were male and White (77.8%). Thirty-three (52.4%) patients had axial pain on presentation without other symptoms, 10 (15.8%) radicular pain, and 20 (31.7%) paresis or paralysis. Mean charges for initial admission were $202,404 (range: 16,237-927,379); total 90-day charges $250,622 (range 29,698-948,020); and 1-year charges $286,731 (range 32,384-1,232,551). Significant predictors of initial admission charges included surgical management (IRR 1.54, 95% CI 1.23-1.90, p<0.001), ambulatory status on admission (nonambulatory vs independent, IRR 1.62, 95% 1.12-2.33, p = 0.009), radicular vs axial symptoms (IRR 1.60, 95% CI 1.21-2.12, p = 0.001), thoracic vs cervical abscess (IRR 1.51, 95% CI 1.11-2.04, p=0.008) and length of stay (IRR 1.04, 95% CI 1.04-1.06, p<0.001). Factors associated with 1-year total charges included nonambulatory status at initial presentation (IRR 2.05, 95% CI 1.28-3.29, p=0.003), paresis/paralysis on presentation (IRR 1.37, 95% CI 1.02-1.83, p=0.034), spinal mechanical instability (IRR 1.89, 95% 1.23-2.93, p=0.004) and length of stay (IRR 1.05, 95% CI 1.03-1.07, p<0.001). Surgical management was not a significant predictor of charges beyond the initial admission. <h3>CONCLUSIONS</h3> Surgical management of spinal epidural abscess patients is associated with increased health care expenditures during the index hospital admission, but not with total costs 1 year after the initial episode. Length of stay, paresis or paralysis on initial presentation and spinal mechanical instability contributed more to increased charges over the first year following management. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.