Research Information System
38th Congress of the European Committee for Treatment and Research in Multiple Sclerosis, Amsterdam, Netherlands, 26 - 28 October 2022, (Unpublished)
Background: Cognitive fatigability has been defined as a decline in cognitive performance during a
sustained cognitive task. Although correlates of subjective fatigue are well-studied in multiple sclerosis
(MS), related factors of cognitive fatigability (CF) are less described. Therefore, we aimed to investigate
determinants of CF in persons with MS (pwMS).
Methods: We administered the Paced Auditory Serial Addition Test (PASAT) and calculated the
percentage change between the first 1/3 part of the test and the last 1/3 part of the test to determine
the cognitive fatigability index (CFI). Brief Repeatable Battery of Neuropsychological Test (BRB-N),
including the Selective Reminding Test (SRT), 10/36 Spatial Recall Test (SPART), Symbol Digit Modalities
Test (SDMT), the Paced Auditory Serial Addition Task 3 s (PASAT 3), and the Word List Generation (WLG)
was applied to 83 pwMS (mean age:35.97±9.55, mean EDSS:1.76±1.18) and 35 age-gender matched
healthy controls (HC). Subjective fatigue, sleepiness, and depression were also assessed.
Results: SPART (r=0.241), SDMT (r=0.327), and Stroop (r=0.233) scores were correlated with CFI. SDMT,
SPART, Stroop, and WLG were significantly associated with CF in the multivariate regression analyses
and explained 12.5% of the variance. Age, neurological disability level according to the EDSS, disease
duration, sleepiness, depression, and subjective were not associated with the CF. There was a non-
significant difference between pwMS and HC on CFI.
Conclusion: Our findings show that cognitive processing speed, visual memory, and verbal fluency are
weakly associated with CF in pwMS. Future work extending the present findings with more detailed
cognitive batteries, especially to the pwMS with higher disability levels, to determine predictors of CF
might be more informative.