Vital Signs And Impaired Cognition In Older Emergency Department Patients: The Apop Study

Background/ObjectivesCognitive impairment is a frequent problem among older patients attending the Emergency Department (ED) and can be the result of pre-existing cognitive impairment, delirium, or neurologic disorders. Another cause can also be acute disturbance of brain perfusion and oxygenation, which may be reversed by optimal resuscitation. This study aimed to assess the relationship between vital signs, as a measure of acute hemodynamic changes, and cognitive impairment in older ED patients.DesignProspective cohort studySettingED's of two tertiary care and two secondary care hospitals in the Netherlands.Participants2629 patients aged 70-years and olderMeasurementsVital signs were measured at the moment of ED arrival as part of routine clinical care. Cognition was measured using the Six-Item Cognitive Impairment Test (6-CIT).ResultsThe median age of patients was 78 years (IQR 74-84). Cognitive impairment was present in 738 patients (28.1%). When comparing lowest with highest quartiles, a systolic blood pressure of < 129 mmHg (OR 1.30, 95% confidence interval (95% CI) 0.98-1.73) was associated with increased risk of cognitive impairment. A higher respiratory rate (> 21/min) was associated with increased risk of impaired cognition (OR 2.16, 95% CI 1.58-2.95) as well as oxygen saturation of < 95% (OR 1.64, 95% CI 1.24-2.19).ConclusionAbnormal vital signs associated with decreased brain perfusion and oxygenation are also associated with cognitive impairment in older ED patients. This may partially be explained by the association between disease severity and delirium, but also by acute disturbance of brain perfusion and oxygenation. Future studies should establish whether normalization of vital signs will also acutely improve cognition.