Incremental contribution of reported previous head injury to the prediction of diagnosis and cognitive functioning in older adults

Background: Severe brain injuries may be a risk factor for the development of dementia in later life. Less severe incidents with relatively short or even no loss of consciousness may not carry the same prognosis. Objectives: This study used data from the first two waves of the Canadian Study of Health and Ageing (CSHA-1 and CSHA-2) to investigate two questions. (1) Does a history of head injury improve the prediction of the diagnosis of dementia? This analysis was based on the 921 elderly individuals who underwent a clinical assessment in CSHA-2 and, 5 years earlier, had reported whether or not they had had a head injury. (2) Does adding information about a history of head injury improve the prediction of neuropsychological test scores? This second analysis included 585 elderly people who underwent neuropsychological assessment in both waves and who also reported whether or not they had had a history of mild or moderate-to-severe head injury. Results: Results showed that the inclusion of head injury information did not improve the prediction of diagnostic outcome of dementia. Age and overall cognitive status were associated with most neuropsychological test scores, more so than the more limited influence of chronic health problems, which was associated with about half of the neuropsychological measures.