Background: Patients who alert the Emergency Medical Services (EMS) system arrive to the hospital sooner and receive faster and more appropriate care after stroke. We investigated the regional distribution of EMS alerts in stroke patients throughout San Diego County. Our aim is to document regional difference that may provide opportunities for improvement in community outreach.
Methods: We included all patients with principle discharge diagnosis of stroke in the San Diego County Stroke Registry from 01/2015 to 12/2015. We analyzed stroke incidence by ZIP code in cases per 100,000 and use of EMS in percent of all stroke discharges by ZIP code. Each ZIP code was characterized by race/ethnicity, age, use of prescriptions for high blood pressure, diabetes and smoking from ESRI Community Analyst. ZIP codes with fewer than 10 stroke cases were excluded. We used Pearson correlation with significance level of p<0.05.
Results: In total we found 5,302 stroke discharges, 4,163 (78.5%) matched to one of 77 ZIP codes in San Diego County. The rate of stroke incidence ranged from 42.9 to 263.9 cases per 100,000 residents. Frequency of EMS use ranged from 26.3% to 83.3%. Rate of stroke was positively correlated with older age, use of prescription drugs for high blood pressure and diabetes. EMS use was higher in ZIP codes with increased smoking (p=0.02). No other variable correlated with EMS use within ZIP codes.
Conclusion: The rate of EMS alert after stroke varies considerably across our region. We did not identify a robust predictor for higher EMS use within a ZIP code. Our data suggests that further studies are needed to best understand the variance in EMS use. The regional difference, however, justify a targeted community outreach program to improve EMS utilization after stroke.