Admission Glasgow Coma Scale Score as a Predictor of Outcome in Patients Without Traumatic Brain Injury

Abstract

Background The Glasgow Coma Scale was developed in 1974 as an injury severity score to assess and predict outcome after traumatic brain injury. The tool is now used to score depth of impaired consciousness in patients with and without traumatic brain injury. However, evidence supporting the use of the Glasgow Coma Scale in the latter group is limited. Objective To assess Glasgow Coma Scale score on hospital admission as a predictor of outcome in patients without traumatic brain injury. Methods This was a secondary analysis of prospectively collected data from 3507 patients admitted to 4 hospitals between October 2015 and October 2019. Patients with a primary diagnosis of traumatic brain injury were excluded from this study. Results The mean age of the 3507 participants in the study was 57 years. Participants were primarily female (52%), White (77%), and non-Hispanic (89%). On admission, 90% of patients had a modified Rankin Scale score of 0 to 3 and 72% had a Glasgow Coma Scale score of 13 to 15 (mild injury). Generalized estimating equation modeling indicated that admission Glasgow Coma Scale score did not predict modified Rankin Scale score at discharge in patients not diagnosed with traumatic brain injury (Glasgow Coma Scale score <8: z = −7.89, P < .001; Glasgow Coma Scale score 8-12: z = −4.17, P < .001). Conclusions The Glasgow Coma Scale is not recommended for use in patients without traumatic brain injury; clinicians should use a more appropriate and validated clinical assessment instrument for this patient population.