Characterizing TIA and stroke symptomatology in a population-based study: implications for and diagnostic value of FAST-based public education

BACKGROUND: Urgent medical treatment is crucial after stroke and transient ischemic attack (TIA), but hindered by extensive prehospital delays. Public education campaigns based on FAST (Face-Arm-Speech-Time) have improved response after major stroke, but not minor stroke and TIA. We aimed to provide strategies to improve public education on a national level, by characterizing TIA and stroke symptoms in a population-based cohort, and extrapolating findings to the general Dutch population.

METHODS: We included all patients with first-ever stroke or TIA from 2002-2016 in the population-based Rotterdam Study (N = 17,931). We determined the prevalence of focal neurological symptoms and their combinations by event severity (i.e., TIA, minor stroke [National Institutes of Health Stroke Scale (NIHSS) 0-3], and major stroke [NIHSS > 3]). We assessed sensitivity of the FAST test for TIA and stroke, and estimated specificity using survey data on the incidence of focal neurological symptoms of non-vascular origin from the same source population. Finally, we determined the diagnostic value of adding visual symptoms and vertigo to the FAST test.

RESULTS: Of all 900 patients (mean age: 77.6 years, 57.2% women), 409 (45.4%) had a TIA, 254 (28.2%) had minor stroke, and 237 (26.3%) had major stroke. At least one FAST symptom was present in 233/237 (98.3%) of patients with major stroke, compared to 186/254 (73.2%) patients with minor stroke, and 250/402 (62.2%) with TIA. Minor strokes and TIA not captured by the FAST test most commonly involved visual symptoms (52.7%), dizziness/vertigo (19.5%), disturbed coordination (19.1%), and sensory disturbance (18.2%). Sensitivity of FAST for TIA/minor stroke increased from 66.4 to 80.8% with the addition of visual symptoms, and to 86.1% with further incorporation of dizziness/vertigo, albeit with a > 40% increase in the number of false positive events. Nearly all patients with major stroke (97.5%) experienced a combination of multiple symptoms, whereas 58.9% of patients with TIA and 26.4% of those with minor stroke reported only a single symptom.

CONCLUSIONS: In contrast to major stroke, sensitivity of the FAST test is limited to around 65% for TIA and minor stroke in a population-based setting. Sensitivity increases by incorporating visual symptoms and vertigo, but this comes with a large number of false positives. Findings of this study may favor a focus on the importance of isolated or transient symptoms, rather than additional symptoms, in future stroke public education campaigns.