Risk of 90-day readmission in patients after firearm injury hospitalization: a nationally representative retrospective cohort study

National conversation has justifiably been concerned with firearm-related deaths and much less attention has been paid to the consequences of surviving a firearm injury. We assessed the risk of hospital readmission, length of stay (LOS) during hospitalization, and costs within 90-days after surviving an index firearm injury and compared these data with pedestrians and occupants involved in motor vehicle crash (MVC). Nationwide Readmission Database, a nationally representative readmission database from 2013 and 2014 was used to create a retrospective cohort study. The primary outcome was time-to-first all-cause readmission within 90-days after discharge from the index hospitalization. Secondary utcomes were LOS and hospitalization costs at index events and at 90-days. There were 3,334 (10.5%), 3,818 (10.6%) and 24,672 (9.4%) firearm injury, pedestrian, and occupant MVC readmissions within 90-days. The risk of 90-day readmission among firearm was 20% (HR=1.20, 5%CI=1.09-1.32) and 34% (HR=1.34, 95%CI=1.26-1.44) greater than patients admitted after pedestrian and occupant MVC. The primary causes of firearm readmission were surgical complications, intestinal disorders and open wounds. The mean total costs were lower among patients after firearm injury versus occupant MVC hospitalizations ($9,357 versus $11,032, p=0.028) but mean total LOS was greater (4.48 versus 4.38 days, p=0.003). Medicaid-insured patients had longer LOS at a total lower cost during index hospitalization after firearm injury as compared to MVC occupant injury. Increased LOS and lower costs of 90-day readmissions among firearm patients versus occupant MVC were irrespective of insurance. The patients surviving a firearm injury have a substantial risk of subsequent hospitalizations, higher than pedestrian or occupant MVC injuries. Medicaid is disproportionately burdened by the costs of treatment of firearm injury.