Longitudinal Changes in Neuropsychological Functioning in Japanese Patients with Myotonic Dystrophy Type 1: A Five Year Follow-Up Study

Abstract

Background: Myotonic dystrophy type 1 (DM1) is a form of muscular dystrophy that causes various symptoms, including those of the central nervous system. Some studies have reported cognitive decline in patients with DM1, although the available evidence is limited. Objective: This study aimed to describe longitudinal differences in neuropsychological function in patients with DM1. Methods: A total of 67 Japanese adult patients with DM1 were investigated using a neuropsychological battery to assess several cognitive domains, including memory, processing speed, and executive function. The patients underwent neuropsychological evaluation approximately five years after baseline (Times 1 and 2). Results: Thirty-eight patients underwent a second neuropsychological evaluation. The participants in the Time 2 evaluation were younger than those who did not participate in Time 2. Patients showed a decline in the Mini-Mental State Examination, Trail Making Test (TMT), Block Design, and Symbol Digit Modalities Test at Time 2 (P < 0.05). Age at Time 1 was associated with a decline in TMT-A and TMT-B scores (rho = 0.57 and 0.45, respectively). Conclusion: These results suggest a cognitive decline in patients with DM1 and warrant further investigation into the possible effects of age-related changes.

Cognitive impairment, neuroimaging abnormalities, and their correlations in myotonic dystrophy: a comprehensive review

“…Moreover, cognitive impairment tends to worsen progressively over time in adult-onset and late-onset forms, suggesting that there may be a positive correlation between cognitive decline and disease duration ( Maresca et al, 2020 ; De Serres-Bérard et al, 2021 ). It provides evidence that brain changes in DM1 are more likely to be neurodegenerative ( Labayru et al, 2019 ; Díaz-Leiva et al, 2020 ; Fujino et al, 2023 ).…”