Cognitive performance in older people after mild traumatic brain injury: Trauma effects and other risk factors.

OBJECTIVE: Cognitive symptoms are common in the initial weeks after mTBI, but recovery is generally expected within three months. However, there is limited information about recovery specifically in older age cohorts. Therefore, this study investigated cognitive outcome three months after mTBI in older adults (≥ 65 years) compared to trauma and community age-matched controls and explored risk factors for outcome after traumatic injury. METHODS: Older mTBI patients (n = 40) and older adults with mild traumatic injury but without head injury (n = 66) were compared to a noninjured community control group (n = 47). Cognitive assessment included neuropsychological and computerized tests. Group differences were compared on individual tasks and overall cognitive performances using composite scores. Regression analyses identified predictors of outcome for trauma patients and moderator analyses explored possible interactions of mTBI severity with age and cognition. RESULTS: As well as lower performances in processing speed and memory, both trauma groups had significantly lower performance on composite neuropsychological (d = .557 and .670) and computerized tasks (d = .783 and .824) compared to noninjured controls. Age, education, and history of depression were direct predictors of cognitive performance after mild traumatic injury (with or without head injury). Further moderation analysis demonstrated that mTBI severity (Glasgow Coma Scale < 15) moderated the impact of older age on computerized assessment (ß = -.138). CONCLUSIONS: Three months after mild trauma (regardless of head injury), older people demonstrate lower cognition compared to noninjured peers. However, severity of mTBI (Glasgow Coma Scale < 15) can interact with older age to predict poorer cognitive outcomes.

Supervisory attentional control following carbon monoxide poisoning.

This study tested the hypothesis that carbon monoxide poisoning would produce a deficit of attentional control, the supervisory attention system, as indexed by attention switching and attentional scheduling, and that routine attentional orienting would be unaffected. Seventy-three cases of carbon monoxide poisoning were assessed at 3 days and 1 month post poisoning on tasks of attentional orienting, and tasks of the supervisory attention system. The results were compared to a group of 53 healthy community participants. A deficit of the supervisory attentional system was documented on a task of attention switching in survivors of both deliberate and accidental CO poisoning, leaving attentional scheduling intact. There was no deficit of attentional orienting in the current study. Alteration of consciousness was found to predict subsequent supervisory attention system impairment in correlation analyses, and the deficit was persistent for a 1 month follow-up period.