Abstract
Objectives The study was performed to identify the individual clinical features and risk factors most strongly associated with the diagnosis of a cerebrovascular cause to transient neurological symptoms (TIA, retinal ischaemia or stroke), as compared to common TIA mimics (including migraine and seizure).
Methods In a retrospective cohort study, all patients presenting with transient neurological symptoms to TIA clinics in Royal Adelaide Hospital and The Queen Elizabeth Hospital (tertiary hospitals) over a two-year period (2019–2020) were included. Clinical features and risk factors were recorded with a standardised form.
Results 1,273 individuals were included. From General Practitioner referrals, the prevalence (estimate of pre-test probability) of a cerebrovascular cause was 25.7% (66/257). From Emergency Department referrals the prevalence was 25.0% (225/899). For individuals with a diagnosis of stroke, the three features with the highest positive likelihood ratio (PLR) were an ABCD2 score of 5 (4.5, 95%CI 3.2–6.2), a past history of peripheral vascular disease (3.3, 95%CI 1.6–6.4) and the presence of limb weakness (3.3, 95%CI 2.7–4.1). These features also had the greatest PLR for a cerebrovascular aetiology (TIA, stroke, or retinal ischaemia). Clinical features that had low PLR for a cerebrovascular cause included positive visual phenomena, memory disturbance (0.2, 95%CI 0–0.45), transient generalised weakness (0.35, 95%CI 0.08–0.79) and confusion (0.35, 95%CI 0.08–0.80).
Conclusions This study demonstrated that specific clinical features and risk factors may be used to distinguish the aetiology of presentations with transient neurological symptoms, that are referred to TIA clinics from General Practitioner and Emergency Department settings.
