Indices of Impaired Self-Awareness in Traumatic Brain Injury Patients with Focal Frontal Lesions and Executive Deficits: Implications for Outcome Measurement

In patients with moderate to severe traumatic brain injury (TBI), impairments of self-awareness are frequently found and associated with worse functional outcome and poor compliance with rehabilitation. The aim of this study was to investigate whether indications of impaired self-awareness could be found in TBI patients with frontal lesions and executive function deficits. Twenty-two TBI patients with focal frontal injuries were compared to 29 TBI patients without focal frontal injuries visible on neuroimaging. No differences were found on several outcome measures, including the Glasgow Outcome Scale-Extended (GOS-E), the Differential Outcome Scale (DOS), and return to work (RTW), although the frontal injury patients were more severely injured as indicated by the Glasgow Coma Scale (GCS) and duration of post-traumatic amnesia (PTA), and had impaired performance on a neuropsychological test of executive functioning. Even more so, the frontal injury group had a significantly lower score on the Sickness Impact Profile (SIP), indicating that they had fewer complaints than the patients without frontal injury, and scored significantly higher on the percentage of recovery (PoR) score, which expresses the extent of recovery as a percentage of their previous level of functioning. In contrast to the non-frontal-injury group, their PoR scores were not related to RTW, reflecting an erroneous perception of their actual working status. The positive results on these different outcome measures, which are partly or entirely self-reported, were seen as an indication of an impaired self-evaluative ability in the frontal injury patients. To determine outcome in a patient with frontal injuries and executive dysfunction, the judgment of several relevant other persons in the patient's life (e.g., partners, therapists, and employers) of the patient's daily life functioning should be sought.