Outcomes After Regionalization of Acute Stroke Care: Time Trend Analysis From Multiple Counties in the State of California

Objective: To determine if regionalization of acute stroke care is associated with IV t-PA use over a five year period. Methods: This is a before-after observational study of all ambulance transported patients with a discharge diagnosis of acute ischemic stroke (AIS). We excluded inter-facility transports and direct admissions. Our data sources were the patient discharge abstract file from the Office of Statewide Health Planning and Development and prehospital records. Probabilistic matching was used to link the records. Relative risk regression was performed to study the independent association of regionalization with IV t-PA use after controlling for patient, hospital demographics and stroke center status. Data analysis was performed using SAS 9.2 Results: Number of ambulance transported AIS patients to 13 hospitals in both counties were 4282 in the “before-phase” and 15571 in the “after-phase” (County 1 “after-phase” n=11368 (73%), County 2 “after-phase” n= 4203 (27%). In the “after-phase”, 10189 (65.4...