Background & Aims

Chronic pain and cognitive dysfunction are two of the most common problems in MS. Up to 55% of people with MS experience clinically significant levels of chronic pain and up to 70% report some type of cognitive dysfunction, including deficits in processing speed or working memory. A potential contributor to changes in cognition is presence and intensity of pain. However, existing studies of the association between pain and cognitive function are limited by reliance on cross-sectional data and use of standard neurocognitive testing protocols that fail to capture within-day intra-individual variability in pain and cognitive function. Understanding such short-term variability in pain and cognitive function in MS may provide crucial information about productive targets for intervention, including real-time interventions that can have immediate effects. The objective of this study was to examine the moment-to-moment (within-person) association between pain and cognitive function in MS.

Methods

This study involved 14 days of ambulatory assessment, with data collected via a smartphone app 4X/day at wake up, two quasi-random time points during the day, and at bedtime. Ecological momentary assessment (EMA) of self-reported pain intensity was rated on a 0-100 numerical rating scale (NRS). Perceived cognitive dysfunction was assessed with three items: slow thinking, foggy thinking, and ability to remember, all rated on a 0-100 NRS and averaged for an overall score (higher scores=greater dysfunction). Objective cognitive deficits were assessed with two brief and reliable cognitive tests assessing processing speed and working memory. Multilevel random effects modeling was used to examine the moment-to-moment association between pain and cognitive dysfunction. Person-centered deviation scores for pain were created to indicate momentary change in pain levels relative to each person’s average pain, thus allowing for the examination of within- and between-person variance separately.

Results

Ambulatory assessments were completed by 227 individuals; out of a possible 56 EMA data points per person, 90.8% (11,547/12,712) were complete. Most participants were female=79.0%, white=72.81%, with mean age=51.14±11.92 and mean EMA pain rating=27.5±22.1. People with higher average pain reported higher perceived cognitive dysfunction (?=0.38; p<0.001) but did not exhibit poorer working memory (?=0.0013; p=0.62) or processing speed (?=-0.74; p=0.90). In contrast, moments of higher-than-average pain at the within-person level were associated with higher perceived cognitive dysfunction (?=0.28; p<0.001) and slower processing speed reaction time (?=1.3; p<0.05) but not poorer working memory (?=0.0003; p=0.6).

Conclusions

Pain intensity and different dimensions of cognitive dysfunction were positively associated at between- and within-person levels in this sample of people with MS. Specifically, momentary increases in pain were associated with worse perceived cognitive dysfunction and slower processing speed at the same moment. Incorporation of ambulatory assessment methods should be considered in the assessment of how pain intensity may relate to cognitive functioning in daily life with an eye toward better understanding of the mechanisms of these associations and development of prevention and treatment strategies.

References

1.Hirsh, A. T., Turner, A. P., Ehde, D. M., & Haselkorn, J. K. (2009). Prevalence and impact of pain in multiple sclerosis: physical and psychologic contributors. Archives of physical medicine and rehabilitation, 90(4), 646–651.
2.Chiaravalloti, N. D., & DeLuca, J. (2008). Cognitive impairment in multiple sclerosis. The Lancet Neurology, 7(12), 1139-1151..
3.Khera, T., & Rangasamy, V. (2021). Cognition and pain: a review. Frontiers in psychology, 12, 1819.
4.Sliwinski, M. J., Mogle, J. A., Hyun, J., Munoz, E., Smyth, J. M., & Lipton, R. B. (2018). Reliability and validity of ambulatory cognitive assessments. Assessment, 25(1), 14-30.
5.Kratz, A. L., Murphy, S. L., & Braley, T. J. (2017). Pain, fatigue, and cognitive symptoms are temporally associated within but not across days in multiple sclerosis. Archives of physical medicine and rehabilitation, 98(11), 2151-2159.

Presenting Author

Sonia Sharma

Poster Authors

Sonia Sharma

PhD

University of Michigan

Lead Author

Keara Ginell

BA

University of Michigan

Lead Author

Nora Fritz

PhD

Wayne State University

Lead Author

Dawn Ehde

PhD

University of Washington

Lead Author

Kevin Alschuler

PhD

University of Washington

Lead Author

Tiffany Braley

MD

University of Michigan

Lead Author

Daniel Whibley

MA

University of Michigan

Lead Author

Anna Kratz

PhD

University of Michigan

Lead Author

Topics

  • Specific Pain Conditions/Pain in Specific Populations: Pain in Chronic/Inflammatory Diseases