Factors associated with missed stroke diagnosis in prehospital triage: a single-center cohort study.

OBJECTIVES

To assess whether patient characteristics, such as sex and living alone, as well as symptom presentation, are associated with a likelihood of a missed stroke diagnosis.

DESIGN

Retrospective cohort study based on registry data from a large comprehensive stroke center in Denmark (2018–2022). Patients with suspected stroke, identified during prehospital evaluation and neurologist teleconsultation, were admitted directly to a stroke unit. Those not suspected of stroke were initially admitted to an emergency department. Patients subsequently diagnosed with stroke after ED admission were classified as missed strokes.

RESULTS

Among 8,361 patients with confirmed stroke (ischemic or hemorrhagic), 1,643 (19.7%) were initially admitted to an ED and later transferred to the stroke unit and was defined as missed strokes. These patients were more often older (75 years vs. 73 years), female (46% vs. 41%), living alone (46% vs. 37%), and fewer had a known time of symptom onset (36% vs. 53%). They presented less frequently with classic focal motor deficits and more often with impaired consciousness, visual field deficits, and aphasia. Among acute ischemic stroke patients, reperfusion therapy was over three times more common in those directly admitted to the stroke unit (36% vs. 10%). In the subgroup treated with reperfusion therapy, symptom differences persisted. Stratified analyses by sex and status of living alone showed that living alone was independently associated with missed stroke (OR 1.51, 95% confidence interval 1.33–1.71), and that women not living alone, more often experienced reduced level consciousness (18% vs. 11%), gaze palsy (20% vs. 11%), and extremity palsies compared to men.

CONCLUSIONS

Nearly one in five confirmed stroke cases were missed in the prehospital phase. Missed strokes were associated with older age, female sex, living alone, and non-motor symptom presentations. Stratified analyses revealed that women, beyond differences in living status, more often presented with distinct symptom profiles. The findings underscore significant limitations in current triage approaches and emphasize the need for better recognition of non-motor stroke presentations.