Effects of acetylcholinesterase inhibitors on cognitive function in patients with chronic traumatic brain injury: A systematic review

Abstract

Objective: To undertake a systematic review of the evidence for the effect of acetylcholinesterase inhibitors (AChEIs) on cognition late after moderate or severe traumatic brain injury.

Background: Cognitive impairment after traumatic brain injury has significant consequences for the individual and society. Cholinergic pathways play an important role in cognitive processing and a hypocholinergic state exists in the chronic phases after traumatic brain injury. AChEIs are already used off-label to treat patients with traumatic brain injury.

Data sources and study selection: PubMed, CINAHL, PsycINFO, the Cochrane Collaboration and Web of Science were searched with pre-specified criteria between 1999 and June 2015.

Data extraction and synthesis: A total of 153 studies were identified. None met pre-specified criteria. The criteria were revised in order to identify studies that may provide useful information despite some risk of bias. Three studies met the revised criteria and were evaluated by 2 reviewers using the Swedish Council on Health Technology Assessment grading system, based on GRADE. Key findings and limitations were tabulated. One study found no effect and 2 found limited effect.

Conclusion: Large randomized controlled studies are needed to establish whether AChEIs are effective for cognition late after moderate or severe traumatic brain injury. Clinicians should be aware of the weak evidence base when considering the off-label use of AChEIs.