451P Gait parameters / cognitive function correlation in a cohort of patients with myotonic dystrophy Type 1: a single-center sensor-based gait analysis.

Myotonic dystrophy type 1 (DM1) patients often present with cognitive impairment and gait abnormalities mostly related to distal muscle weakness, including increased dynamic instability and gait variability. Since an influence of cognitive function on gait has been suggested in several neurological conditions, the aim of this study was to evaluate the mobility changes using mobile health technology (MHT) and their relationship with cognition in DM1. Eight DM1 patients (49 yrs, mean) underwent MHT-based gait analysis (Rehagait, Hasomed) during the six-minute walking test [6MWT] and a one-minute dual-task walking ("check boxes" [CB] and "serial subtraction" [SS]). The dual-task cost (i.e. the difference between the values obtained during the dual task and the values obtained during normal-pace walking, divided by these seconds) was calculated for each parameter. Data were compared with twenty healthy controls (57 years, mean) using an adjusted ANCOVA. Patients underwent an extended neuropsychological battery and a standard neurological assessment. In comparison to HC, DM1 patients showed greater double limb support variability (p = 0.005), step time variability (p = 0.005), and number of steps (p<0.001) in 6MWT. Looking at changes in gait parameters between the three different tasks within the DM1 cohort, patients took longer steps on the 6MWT than on the CB-1MWT (p = 0.030, 0.64 vs. 0.58 mt). In the DM1 cohort, MoCA scores correlated negatively with the number of steps in the 6MWT (r = -0.997, p = 0.003). MoCA scores and Clock's drawing correlated negatively with dual-task cost related to step length variability in both CB- and SS-1MWT. DM1 patients showed greater variability and number of steps in regular walking compared to HC. Our findings suggest that cognitive performance, namely poorer visuo-constructive skills, in DM1 patients might contribute to the observed gait abnormalities and deserve to be validated in larger studies. [ABSTRACT FROM AUTHOR]