Objective: This study aimed to evaluate online remote executive function in individuals with isolated polysomnography (PSG)-confirmed REM sleep behaviour disorder (iRBD).
Background: The Trail Making Task (TMT) assesses executive function. In TMTa, participants sequentially connect 25 encircled numbers in numerical order, while TMTb requires alternating numbers and letters. This online TMT was used in the PREDICT-PD study. Studies show that 32%-50% of iRBD patients develop mild cognitive impairment (MCI)1, and over 90% who phenoconvert to dementia with Lewy bodies (DLB) have MCI at baseline2.
Method: A cross-sectional study was conducted to investigate TMT performance in people with PSG-confirmed iRBD compared to controls. TMT parameters include accuracy (number of errors made), reaction time (time taken to complete the task, milliseconds, ms) for trail A and B and executive function (reaction time difference between trail B and A, milliseconds, ms). We carried out a logistic regression model adjusted for age, sex and education level to determine the association between cognitive parameters and the presence of iRBD.
Results: We included 5798 participants (84 iRBD and 5714 controls). Both groups were comparable in terms of age: individuals with iRBD were 69.1 years (SD 6.8), and controls were 68.1 years (SD 5.5); t(84.57) = -1.27, p=0.21. Compared to controls, the iRBD group were more likely to be male (83.3% vs 40.4%); x-squared (1)= 61.28, p=<0.001. Accuracy was similar between groups (TMTa: 25.1 vs 25.1, p=0.89; TMTb: 24.7 vs 25.2, p=0.06). However, the iRBD group performed both TMTa and TMT b more slowly than controls: TMTa (1511.6 m/s vs 1224.6 m/s, p<0.001) and TMTb (2516.1 vs 1955.9, p<0.001). Executive function was worse for iRBD compared to controls (1004.5 vs 731.3, p=0.002). Adjusted logistic regression analysis showed that TMTb reaction time had the strongest association with iRBD (OR 1.66, 95% CI 1.45 – 1.88, p<0.001). Executive function and TMTa reaction time were also strongly associated with iRBD (OR 1.41, 95% CI 1.21 – 1.63, p<0.001; OR 1.63, 95% CI 1.42 – 1.86, p<0.001, respectively).
Conclusion: Individuals with iRBD showed slower reaction time and worse executive function than controls, likely due to motor impairment and cognitive deficits. These findings highlight the importance of performing cognitive assessments in people with iRBD.
References: 1 Yoon, E.J., Lee, J.Y., Kim, H., Yoo, D., Shin, J.H., Nam, H., Jeon, B. and Kim, Y.K., 2022. Brain metabolism related to mild cognitive impairment and phenoconversion in patients with isolated REM sleep behavior disorder. Neurology, 98(24), pp.e2413-e2424.
2 Génier Marchand, D., Postuma, R.B., Escudier, F., De Roy, J., Pelletier, A., Montplaisir, J. and Gagnon, J.F., 2018. How does dementia with Lewy bodies start? prodromal cognitive changes in REM sleep behavior disorder. Annals of Neurology, 83(5), pp.1016-1026.
To cite this abstract in AMA style:
H. Chohan, T. Periñán, S. Waters, L. Pérez-Carbonell, G. Leschziner, J. Bestwick, A. Schrag, A. Noyce, C. Simonet. Trail Making Task in people with isolated REM sleep behaviour disorder [abstract]. Mov Disord. 2025; 40 (suppl 1). https://www.mdsabstracts.org/abstract/trail-making-task-in-people-with-isolated-rem-sleep-behaviour-disorder/. Accessed October 5, 2025.« Back to 2025 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/trail-making-task-in-people-with-isolated-rem-sleep-behaviour-disorder/