Visuoconstructional impairment in DM1: exploring underlying cognitive processes through the Rey complex figure

Introduction Among the cognitive difficulties shown by myotonic dystrophy type 1 (DM1) patients, visuoconstructional impairment – specifically measured with the Rey-Osterrieth Complex Figure Test (RCFT) – is particularly notable. This study aimed to analyze the performance of DM1 patients and healthy controls (HC) in the RCFT, using different correction systems in order to explore the cognitive processes underlying the poor performance and its associations with other signs and symptoms. Methods Data from 66 DM1 patients and 68 HC were included in this study. All participants had a comprehensive neuropsychological assessment, including the RCFT, which was scored using both the traditional Osterrieth and the Boston Qualitative Scoring System (BQSS) procedures. ANCOVA and Spearman’s correlation analyses were conducted. Results DM1 Patients obtained significantly poorer scores than HC on the RCFT using both correction systems. Regarding BQSS, patients performed worse than HC in both main indexes (Copy Presence Accuracy-CPA and Organization-ORG), and specifically on scores of Configural accuracy, Planning, and Perseveration. Both main indexes – but especially CPA – showed significant and strong correlations with several clinical and cognitive variables. Conclusions Both visuoconstruction and organizational impairments underlie the poor RCFT performance in DM1. Moreover, visuoconstruction ability appears to be sensitive to the clinical hallmarks of DM1 patients. The RCFT is proposed as a gold standard in DM1 assessment and the merits of using alternative scoring systems are discussed.This work was supported by the Institute of Health Carlos III and co-funded by the European Union under Grant number PI17/01231 and PI22/01118; Basque Government under Grant number S-PE13UN030 and 2022111031; and University of the Basque Country (UPV/EHU) under Grant number PIF 20/238 and GU 20/057

Shedding light on motor premanifest myotonic dystrophy type 1: A molecular, muscular and central nervous system follow-up study

Background and purpose Myotonic dystrophy type 1 (DM1) is a hereditary and multisystemic disease that is characterized by heterogeneous manifestations. Although muscular impairment is central to DM1, a premanifest DM1 form has been proposed for those characterized by the absence of muscle signs in precursory phases. Nevertheless, subtle signs and/or symptoms related to other systems, such as the central nervous system (CNS), may emerge and progress gradually. This study aimed to validate the premanifest DM1 concept and to characterize and track affected individuals from a CNS centred perspective. Methods Retrospective data of 120 participants (23 premanifest DM1, 25 manifest DM1 and 72 healthy controls) were analysed transversally and longitudinally (over 11.17 years). Compiled data included clinical, neuropsychological and neuroradiological (brain volume and white matter lesion, WML) measures taken at two time points. Results Manifest DM1 showed significantly more molecular affectation, worse performance on neuropsychological domains, lower grey and white matter volumes and a different pattern of WMLs than premanifest DM1. The latter was slightly different from healthy controls regarding brain volume and WMLs. Additionally, daytime sleepiness and molecular expansion size explained 50% of the variance of the muscular deterioration at follow-up in premanifest individuals. Conclusions Premanifest DM1 individuals showed subtle neuroradiological alterations, which suggests CNS involvement early in the disease. Based on follow-up data, a debate emerges around the existence of a ‘non-muscular DM1’ subtype and/or a premanifest phase, as a precursory stage to other DM1 manifestations.This work was supported by the Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (Ref: 609), from the Institute of Health Carlos III co-founded by Fondo Europeo de Desarrollo Regional (PI17/01231 to A.S.; PI17/01841 to A.L.); Basque Government (S-PE13UN030 to A.S.); and University of the Basque Country (UPV/EHU) (PIF 20/238 to J.G.; GU 20/057 to J.G., G.L. and A.S.)

Patient-reported outcome measures in neuromuscular diseases : a scoping review

Patient-reported outcome measures (PROMs) are valuable in comprehensively understanding patients' health experiences and informing healthcare decisions in research and clinical care without clinicians' input. Until now, no central resource containing information on all PROMS in neuromuscular diseases (NMD) is available, hindering the comparison and choice of PROMs used to monitor NMDs and appropriately reflect the patient’s voice. This scoping review aimed to present a comprehensive assessment of the existing literature on using PROMs in children and adults with NMD. A scoping methodology was followed using Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) and COnsensus-based Standards for the selection of health Measurement Instruments (COSMIN) guidelines to assess the literature on PROMs in NMDs. Eligibility criteria encompassed articles describing psychometric development or evaluation of generic or disease-specific PROM-based instruments for adults and children with specific NMDs. The data charting process involved extracting measurement properties of included PROMs, comprising validity, reliability, responsiveness, and interpretability information. The review identified 190 PROMs evaluated across 247 studies in individuals with NMDs. The majority of PROMs were disease specific. The physical functioning domain was most assessed. Validity was the most frequently investigated measurement property, with a limited number of PROMs sufficiently evaluated for a range of psychometric characteristics. There is a strong need for further research on the responsiveness and interpretability of PROMs and the development of PROMs on social functioning in NMD

White matter integrity changes and neurocognitive functioning in adult-late onset DM1: a follow-up DTI study

[EN] Myotonic Dystrophy Type 1 (DM1) is a multisystemic disease that affects gray and white matter (WM) tissues. WM changes in DM1 include increased hyperintensities and altered tract integrity distributed in a widespread manner. However, the precise temporal and spatial progression of the changes are yet undetermined. MRI data were acquired from 8 adult- and late-onset DM1 patients and 10 healthy controls (HC) at two different timepoints over 9.06 years. Fractional anisotropy (FA) and mean diffusivity (MD) variations were assessed with Tract-Based Spatial Statistics. Transversal and longitudinal intra- and intergroup analyses were conducted, along with correlation analyses with clinical and neuropsychological data. At baseline, reduced FA and increased MD values were found in patients in the uncinate, anterior-thalamic, fronto-occipital, and longitudinal tracts. At follow-up, the WM disconnection was shown to have spread from the frontal part to the rest of the tracts in the brain. Furthermore, WM lesion burden was negatively correlated with FA values, while visuo-construction and intellectual functioning were positively correlated with global and regional FA values at follow-up. DM1 patients showed a pronounced WM integrity loss over time compared to HC, with a neurodegeneration pattern that suggests a progressive anterior–posterior disconnection. The visuo-construction domain stands out as the most sensitive neuropsychological measure for WM microstructural impairment.The present study has been supported by funding from the Institute of Health Carlos III co-founded by Fondo Europeo de Desarrollo Regional-FEDER [Grant Numbers PI17/01231 and PI17/01841], CIBERNED (Grant Number: 609), the Basque Government [SAIO08-PE08BF01] and the University of the Basque Country (Neurosciences group: GIU20-057). BC was supported by a predoctoral grant from the Basque Government [PRE-2020-1-0187]. AJM was supported by a predoctoral grant from the Basque Government [PRE-2019-1-0070]. JG was supported by a predoctoral grant from the University of the Basque Country [PIF20/238]