Does cognitive decline occur decades after moderate to severe traumatic brain injury? A prospective controlled study

ABSTRACT

This prospective controlled study examined long-term trajectories of neuropsychological performance in individuals with traumatic brain injury (TBI) compared to healthy controls, and the impact of IQ, age at injury, time since injury, and injury severity on change over time. Fifty-three individuals with moderate to severe TBI (60.37% male; M = 59.77 yrs, SD = 14.03), and 26 controls (46.15% male; M = 63.96 yrs, SD = 14.42) were studied prospectively (M = 12.72 yrs between assessments). Participants completed measures of premorbid IQ (Weschler Test of Adult Reading), processing speed (Digit Symbol Coding Test), working memory (Digit Span Backwards), memory (Rey Auditory Verbal Learning Test) and executive function (Trail Making Test Part B; Hayling Errors), at a mean of 10.62 yrs (Initial) and 23.91 yrs (Follow-Up) post injury. Individuals with TBI did not show a significantly greater decline in neuropsychological performance over time compared with demographically similar controls. There was no association between change over time with IQ, time since injury or injury severity. Being older at injury had a greater adverse impact on executive function at follow-up. In this small sample, a single moderate to severe TBI was not associated with ongoing cognitive decline up to three decades post injury. Changes in cognitive function were similar between the groups and likely reflect healthy aging.

KEYWORDS:

• Traumatic brain injury
• TBI
• cognition
• cognitive decline
• aging

Acknowledgements

The authors would like to acknowledge the assistance of Olivia McConchie, Dawn Senathi-Raja and Kristy Draper.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

Data are available on reasonable request to the corresponding author. The data are not publicly available due to their containing information that could compromise the privacy of the participants.

Additional information

Funding

This work was supported by the National Health and Medical Research Council (NHMRC) under Grant APP 1127007.