Pain and cognitive performance in adults with multiple sclerosis: A systematic review

Fraser S Brown; Stella A Glasmacher; Daniel Taylor; Ruth Jenkins; Siddharthan Chandran; David Gillespie; Peter Foley

doi:10.1016/j.msard.2023.104584

Pain and cognitive performance in adults with multiple sclerosis: A systematic review

Mult Scler Relat Disord. 2023 Mar:71:104584. doi: 10.1016/j.msard.2023.104584. Epub 2023 Feb 19.

Authors

Fraser S Brown¹, Stella A Glasmacher², Daniel Taylor³, Ruth Jenkins³, Siddharthan Chandran⁴, David Gillespie⁵, Peter Foley⁶

Affiliations

¹ Queen Elizabeth University Hospital, Glasgow, UK. Electronic address: fraser@tonnard.co.uk.
² Anne Rowling Regenerative Neurology Clinic, University of Edinburgh, Chancellor's Building, Edinburgh, UK; Centre for Clinical Brain Sciences, University of Edinburgh, Chancellor's Building, Edinburgh, UK; Department of Neurology, RWTH Aachen University, Aachen, Germany.
³ University of Edinburgh, Edinburgh, UK.
⁴ Anne Rowling Regenerative Neurology Clinic, University of Edinburgh, Chancellor's Building, Edinburgh, UK; Centre for Clinical Brain Sciences, University of Edinburgh, Chancellor's Building, Edinburgh, UK; Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Chancellor's Building, Edinburgh, UK; UK Dementia Research Institute at University of Edinburgh, Chancellor's Building, Edinburgh, UK.
⁵ Department of Clinical Neurosciences, NHS Lothian, Edinburgh, UK.
⁶ Anne Rowling Regenerative Neurology Clinic, University of Edinburgh, Chancellor's Building, Edinburgh, UK; Centre for Clinical Brain Sciences, University of Edinburgh, Chancellor's Building, Edinburgh, UK.

PMID: 36871373
DOI: 10.1016/j.msard.2023.104584

Abstract

Introduction: Pain and cognitive dysfunction are separately known to be important manifestations of multiple sclerosis (MS). Although pain is a complex subjective phenomenon with affective and cognitive aspects, it is not known if people with MS reporting pain are at greater risk of reduced performance in objective tests of cognition. The presence or direction of any association remains to be clarified, as do the roles of confounders such as fatigue, medication and mood.

Methods: We conducted a systematic review of studies examining the relationship between pain and objectively measured cognition in adults with confirmed MS, according to a pre-registered protocol (PROSPERO 42,020,171,469). We carried out searches in MEDLINE, Embase and PsychInfo. Studies of adults with any subtype of MS, with chronic pain and in which cognitive evaluation was conducted by validated instruments were included. We evaluated the role of potential confounders (medication, depression, anxiety, fatigue and sleep) and described findings by eight pre-specified cognitive domains. Risk of bias was assessed using the Newcastle-Ottawa Scale.

Results: 11 studies (n = 3714 participants, range 16 to 1890 per study) were included in the review. Four studies included longitudinal data. Nine studies identified a relationship between pain and objectively measured cognitive performance. In seven of these studies, higher pain scores were associated with poorer cognitive performance. However, no evidence was available for some cognitive domains. Heterogeneous study methodology precluded meta-analysis. Studies infrequently controlled for the specified confounders. Most studies were judged to be at risk of bias.

Discussion: Several studies, but not all, identified a negative relationship between pain severity and objectively measured cognitive performance. Our ability to further characterise this relationship is limited by study design and lack of evidence in many cognitive domains. Future studies should better establish this relationship and delineate the neurological substrate underpinning it.

Keywords: Multiple sclerosis; Pain; cognition.

Publication types

Systematic Review

MeSH terms

Adult
Anxiety
Cognition
Fatigue / complications
Humans
Multiple Sclerosis* / complications
Pain / complications