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%) were transported to primary stroke centers and 14981 (96.2%) were treated at community hospitals. In the “before-phase” IV t-PA was given to 79 patients (1.9%) and in the “after-phase” IV t-PA was given to 514 patients (3.3%). In the model, regionalization was independently associated with higher use of IV t-PA (Overall RR: 2.4 95% CI 1.4, 4.1)
aRR for County 1 - 1.2 95% CI 0.82, 1.65
aRR for County 2 - 2.4 95% CI 1.4, 4.1
Conclusions: Regionalization was associated with higher rates of thrombolysis in AIS patients.
Figure 1: IV t-PA rates before and after regionalization (County 1/County 2)
Table 1: Independent association of regionalization with IV t-PA use