Cost of Chiari I Malformation Surgery: Comparison of Treatment at Children's Hospitals Versus Non-children's Hospitals.

Chiari I malformation is a common entity in pediatric neurosurgery. Prior studies have shown that surgical treatment at children's hospitals (CH) is associated with higher costs compared to non-children's hospitals (NCH) for other diagnoses. Therefore, we hypothesized that costs would be increased for the treatment of Chiari I malformation at a CH. Data were extracted from the Agency for Healthcare Research and Quality's (AHRQ) Healthcare Cost and Utilization Project (HCUP) Kids' Inpatient Database (KID). Patients who underwent surgery for Chiari I malformation were identified using International Classification of Diseases, 9th Edition, Clinical Modification (ICD-9-CM) diagnosis and procedure codes. Univariate statistical tests, multivariable linear regression models, and propensity score matching were utilized to determine differences in hospital length of stay (LOS) and costs between patients treated at CH versus NCH. Treatment at a CH was associated with significantly higher costs compared to treatment at an NCH while hospital LOS and mortality were similar. In the multivariable linear regression model, the adjusted average cost for surgical treatment of Chiari I malformation was $13,716, and treatment at a CH was associated with an additional $6,343 (p<0.0001). Similar results were seen after propensity score matching: costs for treatment at a CH were $6,047 higher than they were for treatment at an NCH (p<0.0001). In our analysis, a significant increase in cost was seen with treatment at a CH while controlling for patient demographics and hospital characteristics, as well as imbalanced covariates between the cohorts. Further investigation is warranted to determine the drivers of increased cost outside of the patient and hospital characteristics we analyzed in our study.