Insurance-Based Differences in Illness Severity and Mortality Risk at the Time of Inferior Vena Cava Filter Placement: A Statewide Health Policy Analysis

Purpose: Inferior vena cava (IVC) filters are frequently placed in patients with contraindications to anticoagulation, often in high-acuity settings. However, payer-associated differences in illness severity and mortality risk at the time of IVC filter placement remain poorly characterized. We evaluated insurance-based patterns in clinical acuity and care delivery using statewide administrative data.

Methods/Materials: We conducted a retrospective analysis of adult inpatient encounters involving IVC filter placement in New York State using the Statewide Planning and Research Cooperative System (SPARCS) database from 2019–2023. Comparative analyses focused on Medicaid and Medicare beneficiaries. Primary outcomes included All Patient Refined Diagnosis-Related Group (APR-DRG)–derived risk of mortality and severity of illness at the time of filter placement. Emergency department (ED) presentation was assessed as a contextual care pathway indicator. Hospital-level case concentration was evaluated descriptively.

Results: A total of 7,748 inpatient encounters involving IVC filter placement were identified statewide. Among Medicaid (n=879) and Medicare (n=5,255) beneficiaries, high APR risk of mortality (major or extreme) was common, occurring in 65.4% of Medicaid and 74.9% of Medicare encounters. Medicare beneficiaries were more frequently classified as extreme mortality risk (38.0% vs 31.3%). High illness severity (APR major or extreme) was observed in 78.6% of Medicaid and 81.8% of Medicare encounters. In both payer groups, IVC filter placement most commonly occurred in the setting of ED presentation. Hospital-level analysis demonstrated concentration of care, with the top 10 hospitals accounting for approximately 26% of statewide IVC filter placements.

Conclusions: IVC filter placement among publicly insured patients occurs largely in high-acuity clinical contexts, with Medicare beneficiaries more frequently represented in the highest illness severity and mortality risk strata. The predominance of emergency presentations and hospital-level concentration highlights opportunities for policy-driven improvements in care coordination and timing of intervention.