Does amantadine maintain function in long-established brain injury? A single case experimental design

ABSTRACT

Objective

The role of dopamine agonist (DA) in restoring consciousness and cognition in recovery phase following acquired brain injury (ABI) is established ⁽¹⁻⁵⁾. The role in later recovery is less well defined. We report a single case experimental design (SCED) trial of amantadine demonstrating improvement in function, six years following ABI.

Method

A scoring system based on established abilities in personal care and interaction was used to identify tasks with component actions, 34 actions in total, each ranked in terms of quality of response to a request or prompt. Actions were scored on maintenance dose amantadine; on withdrawal; and after reintroduction. Daytime sleep duration was also recorded.

Results

At 3^rd and 5^th weeks post withdrawal, deterioration was noted in 27 of 34 graded activities. At 3^rd and 5^th weeks following reintroduction, all but 3 grades returned to baseline or better. Afternoon sleep duration increased from 35 to 80 minutes during withdrawal period returning towards baseline on amantadine resumption.

Conclusion

We believe this provides evidence for benefit of amantadine in sustaining function following ABI. The SCED model used provides a template for others to use to identify comparable change in similar trials.

KEYWORDS:

• Traumatic brain injury
• amantadine
• cognition
• awareness
• functional status

Acknowledgments

Written informed consent for publication of their details was obtained from the study participant and their wife/guardian. The authors would like to thank both for their enthusiasm, suggestions and tolerance for this project.

Declaration of Interests

There are no conflicts of interest to declare.