Glasgow Coma Scale May Underestimate Severity of Isolated Traumatic Brain Injury in Patients ≥ 65 years old
EBM Focus - Volume 10, Issue 37
The Glasgow Coma Scale (GCS) is a simple and well-validated tool used to assess the degree of brain injury in patients with head trauma (SIGN 2009 May PDF). The GCS is not only used as part of the patient assessment to help guide initial treatment and potential transfer to major trauma centers, but it also plays an important role in determining continued patient care and prognosis. Previous reports have suggested that elderly adults with moderate-to-severe traumatic brain injury may have higher presenting GCS scores than younger adults (J Trauma 2004 May;56(5):1042), but that study only had 44 patients aged ≥ 65. A recent retrospective cohort study assessed the GCS scores of 561 patients with significant isolated traumatic brain injury, defined as a head Abbreviated Injury Scale (AIS) score of 3-5 and no additional injuries with an AIS score > 2.
Fifty-seven percent of patients were ≥ 65 years old. There were no significant differences in the distribution of head AIS scores comparing patients ≥ 65 years old to patients
< 65 years old. Presenting GCS scores and survival were significantly different between elderly and younger patients, however (see Table 1 below).
The results of this study suggest that the GCS may be less accurate for predicting the extent of isolated traumatic brain injury in adults ≥ 65 years old compared to younger adults. This is consistent with current guidelines that list age > 65 years as an indication for noncontrast head CT in patients without a loss of consciousness or post-traumatic amnesia (Ann Emerg Med 2008 Dec;52(6):714, NICE 2014 Jan 22:CG176). Given the role of the GCS in assessing and treating patients with traumatic brain injuries, these results are important to consider in the approach to elderly patients with traumatic head injuries.