How does cognition relate to employment in multiple sclerosis? A systematic review

Background: Almost half of people with multiple sclerosis (MS), with low levels of physical disability, are unemployed. It is likely that the impact of invisible symptoms of MS, such as cognition, are involved. Evidence also suggests that cognition is a mediating factor between physical disabilities and unemployment. Methods: A systematic review was conducted to investigate the link between objective cognitive performance and unemployment in MS. The search was carried out in September 2017 using identical search terms across three search engines: PubMed, PSYCH Info and Web of Science. Inclusion criteria included peer review, participant age range of 18 to 65, objective neuropsychological testing and self-reported employment information. Results: The search returned a total of 910 articles of which 13 were considered eligible for inclusion. The eligible studies consistently found that people with MS who were unemployed, or who had more negative work related events, performed less well on neuropsychological tests than both employed people with MS and healthy control groups. People with MS who were employed or had no changes in their work situation also performed less well than healthy controls on neuropsychological tests. Significant between group differences were seen in the following cognitive domains: information processing speed, immediate recall, delayed recall and executive function. Conclusion: Difficulties with employment and/or reduced work hours were associated with cognitive impairment in MS.