A Real-World Assessment of Outcomes, Health Resource Utilization, and Costs Associated with Cerebral Edema in US Patients with Large Hemispheric Infarction

BACKGROUND: Patients with large hemispheric infarction (LHI) are at risk of cerebral edema (CED). This study analyzed health resource use, costs, and outcomes during and after acute hospitalization for LHI in US patients with and without CED. METHODS: Using IBM(®) MarketScan(®) Commercial, Medicaid, and Medicare databases, patients with incident hospitalization for LHI (International Classification of Diseases, Tenth Revision, Clinical Modification diagnosis codes of I63.03x, I63.13x, I63.23x, I63.31x, I63.41x, I63.51x) from 31 March 2016 through 31 December 2018 were identified and further categorized by the presence or absence of CED based on related diagnosis codes or a procedure code of craniectomy. Health resource use, costs, and outcomes were compared in patients with and without CED during hospitalization and after discharge. RESULTS: Of 7336 Commercial, 1946 Medicaid, and 5015 Medicare patients with LHI, 7.8%, 6.9%, and 4.3% had CED, respectively. After adjusting for age, sex, and baseline comorbidities, differences (95% confidence intervals) in mean total costs of the index hospitalization in patients with CED versus without CED were $65,572 ($56,506–$76,335), $44,395 ($26,442–$63,495), and $31,417 ($18,982–$48,543) in the Commercial, Medicaid, and Medicare groups, respectively. Similarly, the adjusted differences (95% confidence intervals) in mean lengths of stay between patients with CED and without CED were 11.75 (10.17–13.48), 10.84 (7.59–14.17), and 3.69 (2.40–5.19) days, respectively. Mortality during index hospitalization was 10–20 times greater in patients with CED versus without CED (p < 0.0001). In those patients who survived and had at least 30-days of follow-up after discharge, CED was also associated with higher post-discharge resource utilization and costs in the commercially insured population who were younger than Medicare patients, and had fewer comorbidities than Medicare and Medicaid patients. This indicates the effect of CED after discharge was particularly burdensome for younger individuals. CONCLUSIONS: In this large cohort study, inpatient mortality, health resource utilization and costs were consistently higher in patients with LHI who developed CED than in those without CED. These findings underscore the need for greater awareness of CED among policymakers and healthcare practitioners. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s41669-021-00294-3.