Predictors of disrupted social participation in myotonic dystrophy type 1

Resistance training in women with myotonic dystrophy type 1: a multisystemic therapeutic avenue

Myotonic dystrophy type 1 (DM1) is a hereditary disease characterized by muscular impairments. Fundamental and clinical positive effects of strength training have been reported in men with DM1, but its impact on women remains unknown. We evaluated the effects of a 12-week supervised strength training on physical and neuropsychiatric health. Women with DM1 performed a twice-weekly supervised resistance training program (3 series of 6-8 repetitions of squat, leg press, plantar flexion, knee extension, and hip abduction). Lower limb muscle strength, physical function, apathy, anxiety and depression, fatigue and excessive somnolence, pain, and patient-reported outcomes were assessed before and after the intervention, as well as three and six months after completion of the training program. Muscle biopsies of the vastus lateralis were also taken before and after the training program to assess muscle fiber growth. Eleven participants completed the program (attendance: 98.5 %). Maximal hip and knee extension strength (p < 0.006), all One-Repetition Maximum strength measures (p < 0.001), apathy (p = 0.0005), depression (p = 0.02), pain interference (p = 0.01) and perception of the lower limb function (p = 0.003) were significantly improved by training. Some of these gains were maintained up to six months after the training program. Strength training is a good therapeutic strategy for women with DM1.

Towards the Identification of Biomarkers for Muscle Function Improvement in Myotonic Dystrophy Type 1

BACKGROUND

Myotonic dystrophy type 1 (DM1) is the most common muscular dystrophy in adults. In DM1 patients, skeletal muscle is severely impaired, even atrophied and patients experience a progressive decrease in maximum strength. Strength training for these individuals can improve their muscle function and mass, however, the biological processes involved in these improvements remain unknown.

OBJECTIVE

This exploratory study aims at identifying the proteomic biomarkers and variables associated with the muscle proteome changes induced by training in DM1 individuals.

METHODS

An ion library was developed from liquid chromatography-tandem mass spectrometry proteomic analyses of Vastus Lateralis muscle biopsies collected in 11 individuals with DM1 pre-and post-training.

RESULTS

The proteomic analysis showed that the levels of 44 proteins were significantly modulated. A literature review (PubMed, UniProt, PANTHER, REACTOME) classified these proteins into biological sub-classes linked to training-induced response, including immunity, energy metabolism, apoptosis, insulin signaling, myogenesis and muscle contraction. Linear models identified key variables explaining the proteome modulation, including atrophy and hypertrophy factors. Finally, six proteins of interest involved in myogenesis, muscle contraction and insulin signaling were identified: calpain-3 (CAN3; Muscle development, positive regulation of satellite cell activation), 14-3-3 protein epsilon (1433E; Insulin/Insulin-like growth factor, PI3K/Akt signaling), myosin-binding protein H (MYBPH; Regulation of striated muscle contraction), four and a half LIM domains protein 3 (FHL3; Muscle organ development), filamin-C (FLNC; Muscle fiber development) and Cysteine and glycine-rich protein 3 (CSRP3).

CONCLUSION

These findings may lead to the identification for DM1 individuals of novel muscle biomarkers for clinical improvement induced by rehabilitation, which could eventually be used in combination with a targeted pharmaceutical approach to improving muscle function, but further studies are needed to confirm those results.

Multiple Case Study of Changes in Participation of Adults with Myotonic Dystrophy Type 1: Importance of Redesigning Accomplishment and Resilience

Background: Myotonic dystrophy type 1 (DM1) is the most prevalent adult form of neuromuscular disorders, for which a decrease of participation with age is known. However, little is known about facilitators and barriers to participation, especially from the perspective of both patients and caregivers. Objective: This study explored and explained changes in participation post-diagnosis with myotonic dystrophy type 1 from the perspective of six adults, their relatives and nurse case managers. Methods: A multiple case study was carried out with these triads (n =  6) using semi-structured individual interviews, medical charts, and a participation patient-reported outcome measure. The six cases were built around three women and three men (age: 40–56 years; disease duration: 19–39 years). Their “relatives” were mainly family members. Nurse case managers had done annual follow-ups with all the adults for approximately ten years. Changes in participation were characterized generally by: 1) heterogeneity, 2) insidious increase in restrictions, and more specifically by: 3) redesigning accomplishment, 4) progressive social isolation, 5) restrictions in life-space mobility, and 6) increasingly sedentary activities. Results: Important facilitators of participation were the adult’s resilience, highly meaningful activities, social support, living arrangement, and willingness to use technical aids. Barriers were mostly related to symptoms and a precarious social network, and were affected by misfit and potential syndemic interactions between personal (e.g., comorbidities) and environmental (e.g., stigma) factors. Conclusion: This study identified key facilitators and barriers and their underlying processes, which should be integrated into the evaluation and intervention framework to optimize participation over time.

Impact of a 12-week strength training program on fatigue, daytime sleepiness, and apathy in men with myotonic dystrophy type 1

Background: Myotonic dystrophy type 1 (DM1) is a multisystemic neuromuscular disorder causing a plea of impairments, of which fatigue and apathy are some of the most frequent non-muscular symptoms. No curative treatment exists to date, and patients only have access to limited effective care, which are intended to decrease the burden of specific symptoms in daily life. Objective: This study aimed to assess whether a 12-week strength-training program has an impact on fatigue/daytime sleepiness, apathy, and patient-reported health in men with DM1. Methods: Eleven participants completed the Fatigue and Daytime Sleepiness Scale (FDSS) and the Myotonic Dystrophy Health Index (MDHI) at baseline, at 6 and 12 weeks, and 6 and 9 months. Also, the Apathy Evaluation Scale (AES) was filled out at baseline, at 12 weeks, and 6 and 9 months. Results: Results show significant effects of the training program both on apathy and fatigue/daytime sleepiness, effects that are respectively greater at three and six months after the end of the program than at its very end. However, no difference was observed regarding the overall disease burden. Conclusion: These findings are promising for patients with DM1 considering that few non-pharmacological treatments are available.

Pharmacological and exercise-induced activation of AMPK as emerging therapies for myotonic dystrophy type 1 patients

Myotonic dystrophy type 1 (DM1) is a multisystemic disorder with variable clinical features. Currently, there is no cure or effective treatment for DM1. The disease is caused by an expansion of CUG repeats in the 3' UTR of DMPK mRNAs. Mutant DMPK mRNAs accumulate in nuclei as RNA foci and trigger an imbalance in the level and localization of RNA-binding proteins causing the characteristic missplicing events that account for the varied DM1 symptoms, a disease mechanism referred to as RNA toxicity. In recent years, multiple signalling pathways have been identified as being aberrantly regulated in skeletal muscle in response to the CUG expansion, including AMPK, a sensor of energy status, as well as a master regulator of cellular energy homeostasis. Converging lines of evidence highlight the benefits of activating AMPK signalling pharmacologically on RNA toxicity, as well as on muscle histology and function, in preclinical DM1 models. Importantly, a clinical trial with metformin, an activator of AMPK, resulted in functional benefits in DM1 patients. In addition, exercise, a known AMPK activator, has shown promising effects on RNA toxicity and muscle function in DM1 mice. Finally, clinical trials involving moderate-intensity exercise also induced functional benefits for DM1 patients. Taken together, these studies clearly demonstrate the molecular, histological and functional benefits of AMPK activation and exercise-based interventions on the DM1 phenotype. Despite these advances, several key questions remain; in particular, the extent of the true implication of AMPK in the observed beneficial improvements, as well as how, mechanistically, activation of AMPK signalling improves the DM1 pathophysiology.

Explanatory factors of dynamic balance impairment in myotonic dystrophy type 1

INTRODUCTION/AIMS

Myotonic dystrophy type 1 (DM1) is a neuromuscular disease affecting many systems and for which muscle weakness is one of the cardinal symptoms. People with DM1 also present with balance-related impairments and high fall risk. The aim of this study was to explore explanatory factors of dynamic balance impairment in the DM1 population.

METHODS

A secondary analysis of data collected as part of a larger study was performed. The Mini Balance Evaluation System Test (Mini-BESTest) was used to assess dynamic balance. Age, sex, and CTG repeat length in blood were retrieved from medical records and research files. The maximal isometric muscle strength of five lower limb muscle groups (hip flexors and extensors, knee flexors and extensors, and ankle dorsiflexors) was quantitatively assessed as well as fatigue. Standard multiple regression analysis was used.

RESULTS

Fifty-two individuals (31 men) aged between 24 and 81 years were included. The final model explains 65.9% of the balance score; ankle dorsiflexor muscle strength was the strongest explanatory factor, followed by CTG repeat length, age and fatigue to a lesser extent.

DISCUSSION

Dynamic balance is impaired in people with DM1. Results of this study suggest that rehabilitation interventions aimed at improving strength of the ankle dorsiflexors and managing fatigue could help to improve dynamic balance in this specific population.

Quality of life and subjective symptom impact in Japanese patients with myotonic dystrophy type 1

BACKGROUND

Although functional impairment in patients with myotonic dystrophy is an important determinant of the quality of life (QoL), patients' subjective evaluation of their symptoms may also affect their QoL. The aim of this study was to investigate the association between subjective symptom impact and the QoL of patients with myotonic dystrophy, after controlling for functional impairment.

METHODS

Eligible patients with myotonic dystrophy type 1 (DM1) were recruited from four hospitals in Japan. The subjective symptom impact of four symptoms (muscle weakness, fatigue, pain, and myotonia) and overall QoL were evaluated using the Individualized Neuromuscular Quality of Life (INQoL) questionnaire. Functional impairment was assessed using the modified Rankin Scale.

RESULTS

Seventy-seven patients with DM1 were included in this study. Overall QoL was significantly associated with subjective symptom impact of muscular weakness, fatigue, pain, myotonia, swallowing difficulty, and droopy eyelids. In the regression models, disease duration (beta = 0.11) and moderate to severe functional impairment (beta = 0.33) explained a significant part of the overall QoL. Furthermore, muscular weakness, fatigue, and myotonia significantly explained additional variance of the overall QoL (beta = 0.17-0.43).

CONCLUSIONS

Subjective symptom impact and functional impairment are independent features influencing the QoL of Japanese patients with DM1.

Effects and Acceptability of an Individualized Home-Based 10-Week Training Program in Adults with Myotonic Dystrophy Type 1

Background: Muscle weakness is a cardinal sign of myotonic dystrophy type 1, causing important functional mobility limitations and increasing the risk of falling. As a non-pharmacological, accessible and safe treatment for this population, strength training is an intervention of choice. Objective: To document the effects and acceptability of an individualized semi-supervised home-based exercise program on functional mobility, balance and lower limb strength, and to determine if an assistive training device has a significant impact on outcomes. Methods: This study used a pre-post test design and men with the adult form of DM1 were randomly assigned to the control or device group. The training program was performed three times a week for 10 weeks and included three exercises (sit-to-stand, squat, and alternated lunges). Outcome measures included maximal isometric muscle strength, 10-Meter Walk Test, Mini-BESTest, 30-Second Chair Stand Test and 6-minute walk test. Results: No outcome measures showed a significant difference, except for the strength of the knee flexors muscle group between the two assessments. All participants improved beyond the standard error of measurement in at least two outcome measures. The program and the device were well accepted and all participants reported many perceived improvements at the end of the program. Conclusions: Our results provide encouraging data on the effects and acceptability of a home-based training program for men with the adult form of DM1. These programs would reduce the financial burden on the health system while improving the clinical services offered to this population.

Predictors of participation restriction over a 9-year period in adults with myotonic dystrophy type 1

PURPOSE

For slowly progressive neuromuscular disease, prognostic approach and long-term monitoring of participation is a crucial part of rehabilitation services. To improve the prognostic approach, professionals must identify individuals at risk of having higher participation restriction. This study aimed to identify personal and environmental predictors of participation restriction over nine years in adults with myotonic dystrophy type 1 (DM1).

METHODS

A secondary analysis of a longitudinal design comparing baseline with a follow-up nine years later was used with a multidimensional assessment of participation and personal and environmental factors. Based on theoretical models, multiple linear regressions were used.

RESULTS

One hundred and fourteen adults with DM1 were included in the study (63.2% women; 78.9% adult onset; mean (SD) age of 43.5 (10.4) years). When age, sex, phenotype, and education were controlled for, participation restriction was predicted by a longer time to stand and walk, lower grip strength, higher body mass index, absence of perceived impact of myotonia in daily living, use of adapted transportation from community services, and perception of obstacle in physical environment (p < 0.001, adjusted R² = 0.50).

CONCLUSIONS

The majority of predictors of participation restriction can be advantageously modified by rehabilitation and environmental changes, such as politics targeting community services provision or physical environment and services accessibility.Implications for rehabilitationPredictors could better inform rehabilitation professional to recognize individuals at risk of higher participation restriction over time and to target specific interventions based on a prognostic approach.Rehabilitation professionals could inform the people living with myotonic dystrophy type 1 and their relatives of the multifactorial nature of occurrence of participation restriction to diminish the "fatality" associated with a genetic progressive disorder.Predictors allow professionals to assess and intervene in the management of specific factors depending on the rehabilitation goal.Identifying individual with myotonic dystrophy with higher risk of participation restriction could help implement a long-term community based rehabilitation intervention plan targeting both personal and environmental factors.

Central Nervous System Involvement as Outcome Measure for Clinical Trials Efficacy in Myotonic Dystrophy Type 1

Increasing evidences indicate that in Myotonic Dystrophy type 1 (DM1 or Steinert disease), an autosomal dominant multisystem disorder caused by a (CTG)n expansion in DMPK gene on chromosome 19q13. 3, is the most common form of inherited muscular dystrophy in adult patients with a global prevalence of 1/8000, and involvement of the central nervous system can be included within the core clinical manifestations of the disease. Variable in its severity and progression rate over time, likely due to the underlying causative molecular mechanisms; this component of the clinical picture presents with high heterogeneity involving cognitive and behavioral alterations, but also sensory-motor neural integration, and in any case, significantly contributing to the disease burden projected to either specific functional neuropsychological domains or quality of life as a whole. Principle manifestations include alterations of the frontal lobe function, which is more prominent in patients with an early onset, such as in congenital and childhood onset forms, here associated with severe intellectual disabilities, speech and language delay and reduced IQ-values, while in adult onset DM1 cognitive and neuropsychological findings are usually not so severe. Different methods to assess central nervous system involvement in DM1 have then recently been developed, these ranging from more classical psychometric and cognitive functional instruments to sophisticated psycophysic, neurophysiologic and especially computerized neuroimaging techniques, in order to better characterize this disease component, at the same time underlining the opportunity to consider it a suitable marker on which measuring putative effectiveness of therapeutic interventions. This is the reason why, as outlined in the conclusive section of this review, the Authors are lead to wonder, perhaps in a provocative and even paradoxical way to arise the question, whether or not the myologist, by now the popular figure in charge to care of a patient with the DM1, needs to remain himself a neurologist to better appreciate, evaluate and speculate on this important aspect of Steinert disease.

Daily activity performance in congenital and childhood forms of myotonic dystrophy type 1: a population-based study

AIMS

To identify and describe the profile characterizing motor and process skills during daily activity performance in individuals with congenital and childhood forms of myotonic dystrophy type 1 (DM1) and to investigate differences in performance between subgroups.

METHOD

Sixty participants (34 males, 26 females, mean age=17y 8mo, SD=6y 0mo, range 5y 8mo-29y 0mo) were divided into severe congenital (n=9), mild congenital (n=20), and childhood (n=31) DM1 subgroups. Daily activity performance was evaluated using a standardized observational instrument: the Assessment of Motor and Process Skills.

RESULTS

Deficits in performance were more pronounced in process than motor skills. Performance more than 2 SDs below age-specific norms was seen in 65% of participants for process skills and 33% of participants for motor skills. The cut-off scores indicated a potential need for assistance in daily activities for 79% of participants older than 18 years of age (n=28) due to deficient process skills.

INTERPRETATION

Extensive deficits in daily activity performance were found in congenital and childhood forms of DM1, mainly owing to deficient process skills. Such skills impact on the ability to perform daily activities and could explain dependency in individuals with DM1. Process skills should be considered when evaluating daily activity performance.

WHAT THIS PAPER ADDS

Young people with myotonic dystrophy type 1 show deficits in motor and process skills when performing daily activities, compared with normative data. Deficits in process skills were more pronounced than deficits in motor skills.

Strength-training effectively alleviates skeletal muscle impairments in myotonic dystrophy type 1

Myotonic dystrophy type 1 (DM1) is a multisystemic disease characterized by progressive muscle weakness. The aim of this project is to evaluate the effects of a 12-week lower limb strength training program in 11 men with DM1. Maximal isometric muscle strength, 30-second sit-to-stand, comfortable and maximal 10-m walk test (10 mwt) were evaluated at baseline, 6 and 12 weeks, and at 6 and 9 months. The one-repetition maximum strength evaluation method of the training exercises was completed at baseline, 6 and 12 weeks. Muscle biopsies were taken in the vastus lateralis at baseline and 12 weeks to evaluate muscle fiber typing and size (including atrophy/hypertrophy factors). Performance in strength and functional tests all significantly improved by week 12. Maximal isometric muscle strength of the knee extensors decreased by month 9, while improved walking speed and 30 second sit-to-stand performance were maintained. On average, there were no significant changes in fiber typing or size after training. Further analysis showed that individual abnormal hypertrophy factor at baseline could explain the different changes in muscle size among participants. Strength training induces maximal isometric muscle strength and lasting functional gains in DM1. Abnormal hypertrophy factor could be a key component to identify high and low responders to hypertrophy in DM1.

Recognition of emotions conveyed by facial expression and body postures in myotonic dystrophy (DM)

INTRODUCTION

Neuromuscular diseases may be of neuropsychological interest insofar as they may affect representations based on embodied cognition theories. Previous studies have shown impaired ability to recognize facial emotions and an association between facial emotion recognition and visuospatial abilities in myotonic dystrophy type 1 (DM1) patients. Here we examined the ability of both DM1 and DM2 patients to recognize emotions expressed by body postures and its relation, and their association with cognitive performance.

METHODS

Participants included 34 DM1 patients, 8 DM2 patients, and 24 healthy control subjects. Emotional recognition ability was assessed through two computerized matching tasks (face and bodies). A neuropsychological battery was used to measure cognition in three domains and global cognition. We used univariate and adjusted linear regression models to investigate the association between cognition and emotion recognition performance.

RESULTS

DM patients (combined DM1 and DM2) performed worse on emotional facial expression (p = .006) and body posture (p = .004) accuracy measures than healthy controls. In linear regression models, DM patients' facial expression accuracy was associated with executive function (p = .013) and visuospatial (p < .001) z-scores. Body posture accuracy was associated with visuospatial (p = .001) and memory (p = .012) z-scores. There were no associations among controls or between cognition and reaction time.

DISCUSSION

These findings suggest that impaired emotional recognition among DM patients is also extended to emotions conveyed by body postures. Consistent with embodied cognition theories, people affected in their body and its movement may have impaired sensorimotor representation in ways that have yet to be fully understood.

Intra-Rater Reliability and Concurrent Validity of Quantified Muscle Testing for Maximal Knee Extensors Strength in Men with Myotonic Dystrophy Type 1

BACKGROUND

Myotonic dystrophy type 1 (DM1) is the most prevalent degenerative neuromuscular disease in adults. Knee extensor (KE) maximal strength loss is a strong indicator of physical limitations in DM1. A reliable, precise and accessible maximal strength evaluation method needs to be validated for this slowly progressive disease.

OBJECTIVE

This paper aims to assess the intra-rater reliability, the standard error of measurement (SEM), the minimal detectable change (MDC), and the concurrent validity of quantified muscle testing (QMT) using a handheld dynamometer with a gold standard: the Biodex isokinetic device.

METHODS

Nineteen men with the adult form of DM1 participated in this study by attending 2 visits spaced by one week. The evaluation of KE muscle strength with QMT was completed on the first visit and the same QMT evaluation in addition to the maximal muscle strength evaluation using an isokinetic device were performed on the second visit.

RESULTS

The intra-rater reliability was excellent with an intraclass correlation coefficient (ICC) of 0.98 (0.96-0.99 : 95% confidence interval). SEM and MDC values were 1.05 Nm and 2.92 Nm, respectively. Concurrent validity of QMT of KE muscle group with the Biodex was also excellent with a Spearman's correlation of ρ= 0.98.

CONCLUSIONS

The excellent concurrent validity and intra-rater reliability, and the small SEM and MDC of the QMT make this test a method of choice, in either a clinical or research setting, to precisely evaluate muscle strength impairments of the KE in men with DM1.

Training program-induced skeletal muscle adaptations in two men with myotonic dystrophy type 1

Objective

The purpose of this side product of another unpublished research project, was to address the effects of a training program on skeletal muscle adaptations of people with myotonic dystrophy type 1 (DM1), under a multifaceted perspective. The objective of this study was to look at training induced muscular adaptations by evaluating changes in muscle strength, myofiber cross-sectional area (CSA), proportion of myofiber types and with indirect markers of muscle growth [proportion of centrally nucleated fibers (CNF) and density of neutrophils and macrophages]. Two men with DM1 underwent a 12-week strength/endurance training program (18 sessions). Two muscle biopsies were obtained pre- and post-training program.

Results

Muscular adaptations occurred only in Patient 1, who attended 72% of the training sessions compared to 39% for Patient 2. These adaptations included increase in the CSA of type I and II myofibers and changes in their proportion. No changes were observed in the percentage of CNF, infiltration of neutrophils and macrophages and muscle strength. These results illustrate the capacity of skeletal muscle cells to undergo adaptations linked to muscle growth in DM1 patients. Also, these adaptations seem to be dependent on the attendance.

Trial registration Clinicaltrials.gov NCT04001920 retrospectively registered on June 26th, 2019

Analysis of the functional capacity outcome measures for myotonic dystrophy

Objectives

Defining clinically relevant outcome measures for myotonic dystrophy type 1 (DM1) that can be valid and feasible for different phenotypes has proven problematic. The Outcome Measures for Myotonic Dystrophy (OMMYD) group proposed a battery of functional outcomes: 6‐minute walk test, 30 seconds sit and stand test, timed 10 m walk test, timed 10 m walk/run test, and nine‐hole peg test. This, however, required a large‐scale investigation,

Methods

A cohort of 213 patients enrolled in the natural history study, PhenoDM1, was analyzed in cross‐sectional analysis and subsequently 98 patients were followed for longitudinal analysis. We aimed to assess: (1) feasibility and best practice; (2) intra‐session reliability; (3) validity; and (4) behavior over time, of these tests.

Results

OMMYD outcomes proved feasible as 96% of the participants completed at least one trial for all tests and more than half (n = 113) performed all three trials of each test. Body mass index and disease severity associate with functional capacity. There was a significant difference between the first and second trials of each test. There was a moderate to strong correlation between these functional outcomes and muscle strength, disease severity and patient‐reported outcomes. All outcomes after 1 year detected a change in functional capacity except the nine‐hole peg test.

Conclusions

These tests can be used as a battery of outcomes or independently based on the shown overlapping psychometric features and strong cross‐correlations. Due to the large and heterogeneous sample of this study, these results can serve as reference values for future studies.

Secondary health conditions and social role satisfaction in adults with long-term physical disability

OBJECTIVE

Individuals living with physical disability due to early acquired or traumatic conditions often experience a range of psychological and physical health problems that are associated with their condition but are not directly caused by it. Known as "secondary health conditions," these problems can interact with existing functional limitations and other medical comorbidities to limit social participation. The current study assessed the concurrent and longitudinal associations between secondary health conditions, chronic medical comorbidities, and functional limitations, with a PROMIS® measure of social role participation.

METHODS

A longitudinal survey study of community-dwelling adults with one of four chronic physical conditions (multiple sclerosis, muscular dystrophy, spinal cord injury, postpoliomyelitis syndrome). The baseline survey (T1) was mailed to 2041 individuals, and1862 baseline surveys were completed and returned (91% response rate). The follow-up survey (T2) was mailed roughly three years later; 1594 completed and returned the T2 survey (86% of T1 survey completers).

RESULTS

Multiple linear regression analyses revealed that secondary health conditions, functional impairments, and chronic medical comorbidities accounted for 52% of the variance in satisfaction with social roles concurrently at T1. The amount of variance of change in satisfaction with social roles over the ∼3-year period accounted for by these variables was 3%. Functional limitations and more psychologically oriented secondary conditions were the strongest predictors of satisfaction with social roles.

CONCLUSIONS

Findings suggest that, for people with disabilities, addressing psychologically oriented secondary health conditions may be as important as functional impairment in predicting long-term social health. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Uncovering health and social care needs among myotonic dystrophy patients: Utility of the Needs and Provisions Complexity Scale

OBJECTIVES

Myotonic dystrophy type 1 (DM1) is a slowly progressive multisystem disorder. Guidelines recommend multidisciplinary follow-up. We aimed to investigate the presence of unmet health and social care needs among patients with DM1 and whether unmet needs correlated with motor function, cognitive impairments, or quality of life.

MATERIAL AND METHODS

Patients were 22 adults with DM1. "Needs and Provisions Complexity Scale" (NPCS) was applied to evaluate the individual's needs and provision of health and social services. The Muscular Impairment Rating Scale (MIRS) was used to measure motor function and disease stage. All patients underwent neuropsychological testing. The EQ-5D-3L questionnaire was used to evaluate the patients' health-related quality of life (HRQoL).

RESULTS

Median time from diagnosis was 11 years (range: 1-40). Twenty patients had developed needs related to social care, personal care, and rehabilitation that had not been met, whereas need for medical follow-up was largely met. The more pronounced the muscular impairment, the more unmet needs were experienced by DM1 patients (r = 0.50, P = 0.019). Degree of unmet needs did not correlate with full-scale IQ (r = -0.27, P = 0.23) or HRQoL (r = -0.14, P = 0.55).

CONCLUSION

Using NPCS, we discovered that patients with DM1 had unmet needs with respect to social care, personal care, and rehabilitation although their need for medical follow-up was met. Thus, the use of NPCS helped bring our practice in better accordance with guidelines. A higher MIRS grade should alert the clinician to the likelihood of unmet needs.

Perceived fatigue in myotonic dystrophy type 1: a case-control study

Background

The aim of this study was to explore perceived fatigue, experienced functional limitations due to fatigue and clinical correlates in patients with Myotonic Dystrophy type 1 (DM1).

Methods

In total, 32 consecutive patients with DM1 (14 women and 18 men) and 30 sex, age and education matched healthy control subjects participated. Perceived fatigue was rated on the Fatigue Impact Scale (FIS). Patients also completed a set of assessments aimed to characterize CTG-repeat size, muscle impairment, depression and cognitive functions. Non-parametric analysis were performed as appropriate, including Mann-Whitney U-test and Spearman correlation test.

Results

DM1 patients had higher FIS total score than healthy controls, suggesting higher fatigue levels. More specifically, DM1 patients scored higher on the FIS physical and psychosocial subscales than controls but not on the FIS cognitive scale. Scores on fatigue correlated significantly with muscle impairment and depression.

Conclusions

Perceived fatigue is significantly more common in patients with DM1 than in healthy controls. Higher ratings on depression and muscle impairment were associated with the condition. This indicates that both depression and muscle impairment may contribute to the experience of fatigue in DM1.

Impact of secondary health conditions on social role participation for a long-term physical disability cohort

For people living with long-term physical disability (LTPD) social participation may involve managing physical impairments and secondary health conditions (SHCs) that are not due to the pathophysiology of the LTPD diagnosis itself. Prior research found a negative relationship between SHCs and participation in social roles in people with spinal cord injury (SCI). We expand on this research by investigating the influence of SHCs on participation in social roles for people with one of four LTPDs, controlling for co-variates. We (1) evaluated the associations between SHCs and participation in social roles; and (2) determined whether SHCs on individuals' ability to participate in social roles varies by type of diagnosis in those aging with either SCI, muscular sclerosis, muscular dystrophy, or post-polio syndrome. Cross-sectional, secondary data analysis from a return-by-mail survey. N = 1,573. Data were analyzed with multiple linear regressions (hypothesis 1), and then three moderated regressions (hypothesis 2). After controlling for demographics, SHCs were associated with lower ability to participate in social roles and accounted for 48% of the variance (all p's <.001). The relationship between depression and social role participation was moderated by diagnosis, such that depression was more negatively associated with social participation among individuals with SCI (p = .020). Thus, SHC negatively impact participation in social roles.

What is known about the effects of exercise or training to reduce skeletal muscle impairments of patients with myotonic dystrophy type 1? A scoping review

BACKGROUND

Myotonic dystrophy type 1 (DM1) is a neuromuscular disease characterized by multisystemic involvements including a progressive loss of maximal muscle strength and muscle wasting. Poor lower-limb strength is an important factor explaining disrupted social participation of affected individuals. This review aims to map what is known about the effects of exercise and training programs undertaken to counteract skeletal muscle impairments in DM1 patients.

METHODS

Medline, CINAHL and EMBASE databases were searched. Regarding study eligibility, title and abstract of 704 studies followed by 45 full articles were reviewed according to the following eligibility criteria. Inclusion: (1) humans with DM1 and (2) experimental protocol relying on exercise or training. Exclusion: (1) studies that do not evaluate skeletal muscle responses or adaptations, (2) reviews covering articles already included and (3) pharmacological intervention at the same time of exercise or training program.

RESULTS

Twenty-one papers were selected for in-depth analysis. Different exercise or training protocols were found including: acute exercise, neuromuscular electric stimulation, strength training, aerobic training, balance training and multiple rehabilitation interventions. Seven studies reported clinical measurements only, five physiological parameters only and nine both types.

CONCLUSION

This scoping review offers a complete summary of the current scientific literature on the effect of exercise and training in DM1 and a framework for future studies based on the concomitant evaluation of the several outcomes in present literature. Although there were a good number of studies focusing on clinical measurements, heterogeneity between studies does not allow to identify what are the adequate training parameters to obtain exercise or training-induced positive impacts on muscle function. Scientific literature is even more scarce regarding physiological parameters, where much more research is needed to understand the underlying mechanisms of exercise response in DM1.

Structural white matter networks in myotonic dystrophy type 1

The myriad of neuropsychiatric manifestations reported in myotonic dystrophy type 1 may have its origin in alterations of complex brain network interactions at the structural level. In this study, we tested the hypothesis that altered white matter microstructural integrity and network organisation were present in a cohort of individuals with DM1 compared to unaffected controls, which was expected to be associated with CNS related disease manifestations of DM1. We performed a cross-sectional neuropsychological assessment and brain MRI in 25 myotonic dystrophy type 1 (DM1) patients and 26 age, sex and educational level matched unaffected controls. Patients were recruited from the Dutch cohort of the OPTIMISTIC study, a concluded trial which had included ambulant, genetically confirmed DM1 patients who were severely fatigued. We applied graph theoretical analysis on structural networks derived from diffusion tensor imaging (DTI) data and deterministic tractography to determine global and local network properties and performed group-wise comparisons. Furthermore, we analysed the following variables from structural MRI imaging: semi-quantitative white matter hyperintensity load andwhite matter tract integrity using tract-based spatial statistics (TBSS). Structural white matter networks in DM1 were characterised by reduced global efficiency, local efficiency and strength, while the network density was compatible to controls. Other findings included increased white matter hyperintensity load, and diffuse alterations of white matter microstructure in projection, association and commissural fibres. DTI and network measures were associated (partial correlations coefficients ranging from 0.46 to 0.55) with attention (d2 Test), motor skill (Purdue Pegboard test) and visual-constructional ability and memory (copy subtest of the Rey-Osterrieth Complex Figure Test). DTI and network measures were not associated with clinical measures of fatigue (checklist individual strength, fatigue subscale) or apathy (apathy evaluation scale - clinician version). In conclusion, our study supports the view of brain involvement in DM1 as a complex network disorder, characterised by white matter network alterations that may have relevant neuropsychological correlations. This work was supported by the European Community's Seventh Framework Programme (FP7/2007-2013; grant agreement n° 305,697) and the Marigold Foundation.

The Measure of Quality of the Environments' Turkish Validity and Reliability

The aim of this study was to translate the Measure of Quality of the Environment-Short Form (MQE-SF) into Turkish language and to evaluate the validity and reliability. The MQE-SF was culturally adapted via an internationally suggested method. A total of 185 volunteers with disabilities (age range = 18-55 y/o, 107 males; 78 females) from the Disabled People Association of Turkey completed the MQE-SF. To evaluate the MQE-SF's criterion/concurrent validity, the Craig Hospital Inventory of Environmental Factors (CHIEF) was also administered. Test-retest reliability was evaluated by administering MQE-SF to 85 participants a second time within 14 days of initial administration. The alpha coefficient measuring the internal consistency of the questionnaire were .84 and .83. The criterion-related validity was moderate between the MQE-SF Barriers and the CHIEF (r = -.46, p < .05). The questionnaire was moderately reliable in terms of the test-retest reliability (r = .69, .70 p < .05). The Turkish adaptation of the MQE-SF had good internal consistency and moderate criterion-related validity as well as test-retest reliability for people with disabilities.

Participation and the Role of Neuropsychological Functioning in Myotonic Dystrophy Type 1

BACKGROUND

Myotonic Dystrophy type 1 (DM1) is primarily a neuromuscular disease but can also have neuropsychological consequences (i.e.cognitive, emotional and behavioural) which can influence daily living and societal participation. Not much is known about the level of participation of DM1 patients and their relatives and the factors influencing participation. This information can guide the development of rehabilitation programs and identify those at risk of long-term participation problems.

OBJECTIVE

To investigate the level of participation of DM1 patients and their partners and the determinants.

METHODS

Cross-sectional study using the Utrecht Scale for Evaluation of Rehabilitation-Participation. Determinants were demographic, disease related, and neuropsychological characteristics. Spearman correlations and backward multiple regression analyses were performed.

RESULTS

Of the 66 DM1 participants, 54% reported severe fatigue and 47% apathy. Experienced participation restrictions were most prevalent in housekeeping (74%), sports (68%) and outdoor activities (55%). Participants were relatively satisfied with their level of participation, but dissatisfaction occurred mostly in housekeeping (58%), outdoor activities (55%), and sports (54%). Age and apathy were significant predictors of frequency of (R2 = 10.4) and restrictions in participation in the multivariate model (R2 = 14.4). Emotional functioning was the only significant predictor of satisfaction with participation (R2 = 23.8).

CONCLUSIONS

A considerable number of DM1 patients have Central Nervous System-related problems such as fatigue and apathy in addition to neuromuscular restrictions. Risk factors for lower participation are age, apathy, and emotional problems. Physical as well as neuropsychological rehabilitation programs are recommended.

A. Social cognition in myotonic dystrophy type 1: Specific or secondary impairment?

AIMS

The cognitive profile of Myotonic Dystrophy type 1 (DM1) has been described in recent decades. Moreover, DM1 patients show lowered social engagement and difficulties in social-cognitive functions. The aim of the present study is to explore whether social cognition impairment is present in DM1 taking into account the overall cognitive condition.

METHOD

38 patients and a control group paired in age and gender participated in the study. All the participants had an IQ within the normal range. Subjects were administered an abbreviated neuropsychological battery which comprised a facial emotion recognition test (POFA) and Faux Pas Test, as well as a self-report questionnaire on cognitive and affective empathy (TECA).

RESULTS

Statistically significant differences were found only for facial emotion recognition (U = 464.0, p = .006) with a moderate effect size (.31), with the controls obtaining a higher score than the patients. Analyzing each emotion separately, DM1 patients scored significantly lower than controls on the recognition of anger and disgust items. Emotion recognition did not correlate with genetic load, but did correlate negatively with age. No differences were found between patients and controls in any of the other variables related to Theory of Mind (ToM) and empathy.

CONCLUSION

DM1 does not manifest specific impairments in ToM since difficulties in this area predominantly rely on the cognitive demand of the tasks employed. However, a more basic process such as emotion recognition appears as a core deficit. The role of this deficit as a marker of aging related decline is discussed.

Cognitive behavioural therapy with optional graded exercise therapy in patients with severe fatigue with myotonic dystrophy type 1: a multicentre, single-blind, randomised trial

BACKGROUND

Myotonic dystrophy type 1 is the most common form of muscular dystrophy in adults and leads to severe fatigue, substantial physical functional impairment, and restricted social participation. In this study, we aimed to determine whether cognitive behavioural therapy optionally combined with graded exercise compared with standard care alone improved the health status of patients with myotonic dystrophy type 1.

METHODS

We did a multicentre, single-blind, randomised trial, at four neuromuscular referral centres with experience in treating patients with myotonic dystrophy type 1 located in Paris (France), Munich (Germany), Nijmegen (Netherlands), and Newcastle (UK). Eligible participants were patients aged 18 years and older with a confirmed genetic diagnosis of myotonic dystrophy type 1, who were severely fatigued (ie, a score of ≥35 on the checklist-individual strength, subscale fatigue). We randomly assigned participants (1:1) to either cognitive behavioural therapy plus standard care and optional graded exercise or standard care alone. Randomisation was done via a central web-based system, stratified by study site. Cognitive behavioural therapy focused on addressing reduced patient initiative, increasing physical activity, optimising social interaction, regulating sleep-wake patterns, coping with pain, and addressing beliefs about fatigue and myotonic dystrophy type 1. Cognitive behavioural therapy was delivered over a 10-month period in 10-14 sessions. A graded exercise module could be added to cognitive behavioural therapy in Nijmegen and Newcastle. The primary outcome was the 10-month change from baseline in scores on the DM1-Activ-c scale, a measure of capacity for activity and social participation (score range 0-100). Statistical analysis of the primary outcome included all participants for whom data were available, using mixed-effects linear regression models with baseline scores as a covariate. Safety data were presented as descriptives. This trial is registered with ClinicalTrials.gov, number NCT02118779.

FINDINGS

Between April 2, 2014, and May 29, 2015, we randomly assigned 255 patients to treatment: 128 to cognitive behavioural therapy plus standard care and 127 to standard care alone. 33 (26%) of 128 assigned to cognitive behavioural therapy also received the graded exercise module. Follow-up continued until Oct 17, 2016. The DM1-Activ-c score increased from a mean (SD) of 61·22 (17·35) points at baseline to 63·92 (17·41) at month 10 in the cognitive behavioural therapy group (adjusted mean difference 1·53, 95% CI -0·14 to 3·20), and decreased from 63·00 (17·35) to 60·79 (18·49) in the standard care group (-2·02, -4·02 to -0·01), with a mean difference between groups of 3·27 points (95% CI 0·93 to 5·62, p=0·007). 244 adverse events occurred in 65 (51%) patients in the cognitive behavioural therapy group and 155 in 63 (50%) patients in the standard care alone group, the most common of which were falls (155 events in 40 [31%] patients in the cognitive behavioural therapy group and 71 in 33 [26%] patients in the standard care alone group). 24 serious adverse events were recorded in 19 (15%) patients in the cognitive behavioural therapy group and 23 in 15 (12%) patients in the standard care alone group, the most common of which were gastrointestinal and cardiac.

INTERPRETATION

Cognitive behavioural therapy increased the capacity for activity and social participation in patients with myotonic dystrophy type 1 at 10 months. With no curative treatment and few symptomatic treatments, cognitive behavioural therapy could be considered for use in severely fatigued patients with myotonic dystrophy type 1.

FUNDING

The European Union Seventh Framework Programme.

Analyzing walking speeds with ankle and wrist worn accelerometers in a cohort with myotonic dystrophy

Background: Accelerometers are accurate tools to assess movement and physical activity. However, interpreting standardly used outputs is not straightforward for populations with impaired mobility.

Methods: The applicability of GENEActiv was explored in a group of 30 participants with myotonic dystrophy and compared to a group of 14 healthy-controls. All participants performed a set of tests while wearing four different accelerometers (wrists and ankles): [1] standing still; [2] ten-meters walk test; [3] six-minutes walking test; and, [4] ten-meters walk/run test.

Results: Relevant findings were: [1] high intra-accelerometer reliability (i.e. 0.97 to 0.99; p < 0.001); [2] each test acceleration values differ significantly between each other; [3] no inter-accelerometer reliability between wrist-worn devices and ankle-worn; and [4] a significant difference between the myotonic dystrophy group and the healthy-controls detectable at each test (i.e. Left-ankle values at six-minutes walking test: 48±17 for the myotonic dystrophy group, vs, 74±16 for the healthy-controls; p < 0.001).

Conclusions: GENEActiv demonstrated to be valid and reliable, capable of detecting walking periods and discriminating different speeds. However, inter-accelerometer reliability only applied when comparing opposite sides of the same limb. Specific movement characteristics of the myotonic dystrophy group were identified and muscle strength showed not to be a full determinant of limb acceleration.

Implications for rehabilitation

Rehabilitation professionals in the field of neuromuscular disorders should be aware of the potential use of objective monitoring tools such as accelerometers whilst acknowledging the implications of assessing populations with altered movement patterns.

Researchers should be cautious when translating accelerometry outputs previously validated in healthy populations to functionally impaired cohorts like myotonic dystrophy.

Accelerometers can objectively expose movement disturbances allowing further investigations for the source of these disturbances.

A 9-year follow-up study of quantitative muscle strength changes in myotonic dystrophy type 1

Myotonic dystrophy type 1 (DM1) is a neuromuscular disorder presenting with major muscle impairments. However, few studies have addressed muscle strength progression using quantitative methods. The aims of this study were to document muscle strength changes in eight muscle groups among adults with DM1 over a 9-year period, and to compare this progression between phenotypes (adult and late-onset) and sex. Patients with a genetic diagnosis of DM1 with the late-onset or the adult phenotype were recruited at baseline through the clinical registry of the Saguenay Neuromuscular Clinic. The maximum isometric muscle strength was measured at baseline and 9 years later using a standardized protocol of quantitative muscle testing. Muscle groups included were shoulder abductors, elbow flexors/extensors, wrist extensors, hip flexors, knee flexors/extensors, and ankle dorsiflexors. For the whole group, a mean loss of 24.5-52.8% was observed over the 9-year period for all muscle groups, except for hip flexors which remained stable. Generally, men were stronger and showed a significant greater rate of decline of muscle strength than women. The adult and late-onset phenotypes taken separately also showed a significant and similar decline over the 9-year period, except for the wrist and knee extensors where muscle strength of participants with the adult phenotype decreased faster than in the late-onset phenotype. The similar rate of decline of muscle strength loss observed between phenotypes highlights the need to develop interventions to prevent this decline, even for patients with the late-onset phenotype who are often considered as mildly impaired, and therefore neglected by the rehabilitation services.

Can Human Pluripotent Stem Cell-Derived Cardiomyocytes Advance Understanding of Muscular Dystrophies?

Muscular dystrophies (MDs) are clinically and molecularly a highly heterogeneous group of single-gene disorders that primarily affect striated muscles. Cardiac disease is present in several MDs where it is an important contributor to morbidity and mortality. Careful monitoring of cardiac issues is necessary but current management of cardiac involvement does not effectively protect from disease progression and cardiac failure. There is a critical need to gain new knowledge on the diverse molecular underpinnings of cardiac disease in MDs in order to guide cardiac treatment development and assist in reaching a clearer consensus on cardiac disease management in the clinic. Animal models are available for the majority of MDs and have been invaluable tools in probing disease mechanisms and in pre-clinical screens. However, there are recognized genetic, physiological, and structural differences between human and animal hearts that impact disease progression, manifestation, and response to pharmacological interventions. Therefore, there is a need to develop parallel human systems to model cardiac disease in MDs. This review discusses the current status of cardiomyocytes (CMs) derived from human induced pluripotent stem cells (hiPSC) to model cardiac disease, with a focus on Duchenne muscular dystrophy (DMD) and myotonic dystrophy (DM1). We seek to provide a balanced view of opportunities and limitations offered by this system in elucidating disease mechanisms pertinent to human cardiac physiology and as a platform for treatment development or refinement.

Increased EEG Theta Spectral Power in Sleep in Myotonic Dystrophy Type 1

STUDY OBJECTIVES

Myotonic dystrophy type 1 (DM1) is a multisystemic disorder that involves the central nervous system (CNS). Individuals with DM1 commonly present with sleep dysregulation, including excessive daytime sleepiness and sleep-disordered breathing. We aim to characterize electroencephalogram (EEG) power spectra from nocturnal polysomnography (PSG) in patients with DM1 compared to matched controls to better understand the potential CNS sleep dysfunction in DM1.

METHODS

A retrospective, case-control (1:2) chart review of patients with DM1 (n = 18) and matched controls (n = 36) referred for clinical PSG at the Stanford Sleep Center was performed. Controls were matched based on age, sex, apnea-hypopnea index (AHI), body mass index (BMI), and Epworth Sleepiness Scale (ESS). Sleep stage and respiratory metrics for the two groups were compared. Power spectral analysis of the EEG C3-M2 signal was performed using the fast Fourier transformation.

RESULTS

Patients with DM1 had significantly increased theta percent power in stage N2 sleep compared to matched controls. Theta/beta and theta/alpha percent power spectral ratios were found to be significantly increased in stage N2, N3, all sleep stages combined, and all wake periods combined in patients with DM1 compared to controls. A significantly lower nadir O2 saturation was also found in patients with DM1 versus controls.

CONCLUSIONS

Compared to matched controls, patients with DM1 had increased EEG theta spectral power. Increased theta/beta and theta/alpha power spectral ratios in nocturnal PSG may reflect DM1 pathology in the CNS.

[Understanding people with Steinert’s disease to provide them with better care.]

INTRODUCTION

the lifestyles of individuals with myotonic dystrophy type 1 (DM1), also known as Steinert’s disease, are poorly understood and yet they need to be considered when it comes to effective long-term care. The nursing care provided in referral centers is mindful of the clinical diversity of Steinert’s disease when it comes to interdisciplinary care, but the disease is more complex from a relational point of view. The objective of this qualitative study was to understand the life experiences of individuals with Steinert’s disease, by looking at the limitations of their bodies and the adaptation strategies they develop.

METHOD

this social science and nursing science study examines this problem of care, adopting an ethno-sociological perspective.

RESULTS

The study brought to light the changes that Steinert’s disease imposes on a body. These changes contribute to individuals’ construction of a body schema and social identity, which, despite allowing them to maintain a “normal” daily life for as long as possible, can also reach limits, requiring them to make radical life changes. The study’s results are discussed using an analytical framework based on the four different ways of interpreting the body proposed by Nicolas Vonarx: the “material body,” the “able body,” the “feeling body,” and the “knowing/judging body.” To discuss the role the body plays for people living with Steinert’s disease within a normative society, we propose that the concept of the “socializing body” be added to this framework.

A More Efficient Transportable and Scalable System for Real-Time Activities and Exercises Recognition

Many people in the world are affected by muscle wasting, especially the population hits by myotonic dystrophy type 1 (DM1). Those people are usually given a program of multiple physical exercises to do. While DM1 and many other people have difficulties attending commercial centers to realize their program, a solution is to develop such a program completable at home. To this end, we developed a portable system that patients could bring home. This prototype is an improved version of the previous one using Wi-Fi, as this new prototype runs on BLE technology. This new prototype conceptualized induces great results.

Cognitive impairment and quality of life in patients with myotonic dystrophy type 1

INTRODUCTION

This study sought to clarify whether specific cognitive abilities are impaired in patients with myotonic dystrophy type 1 (DM1) as well as to investigate the relationships among quality of life (QoL), cognitive function, and psychological factors.

METHODS

Sixty patients with DM1 were evaluated on cognitive functioning (abstract reasoning, attention/working memory, executive function, processing speed, and visuoconstructive ability), apathy, depression, excessive daytime sleepiness, fatigue, and QoL. QoL was assessed by 2 domains of the Muscular Dystrophy Quality of Life Scale (Psychosocial Relationships and Physical Functioning and Health).

RESULTS

More than half of the patients exhibited cognitive impairment in attention/working memory, executive function, processing speed, and visuoconstructive ability. The Psychosocial Relationships factor was associated with processing speed, attention/working memory, and apathy, whereas depression and fatigue were associated with 2 QoL domains.

DISCUSSION

Our study identified specific cognitive impairments in DM1. Specific cognitive functions and psychological factors may be potential contributors to QoL. Muscle Nerve 57: 742-748, 2018.

Survey of Canadian Myotonic Dystrophy Patients' Access to Computer Technology

BACKGROUND

Myotonic dystrophy type 1 is an autosomal dominant condition affecting distal hand strength, energy, and cognition. Increasingly, patients and families are seeking information online. An online neuromuscular patient portal under development can help patients access resources and interact with each other regardless of location. It is unknown how individuals living with myotonic dystrophy interact with technology and whether barriers to access exist. We aimed to characterize technology use among participants with myotonic dystrophy and to determine whether there is interest in a patient portal.

METHODS

Surveys were mailed to 156 participants with myotonic dystrophy type 1 registered with the Canadian Neuromuscular Disease Registry.

RESULTS

Seventy-five participants (60% female) responded; almost half were younger than 46 years. Most (84%) used the internet; almost half of the responders (47%) used social media. The complexity and cost of technology were commonly cited reasons not to use technology. The majority of responders (76%) were interested in a myotonic dystrophy patient portal.

CONCLUSIONS

Patients in a Canada-wide registry of myotonic dystrophy have access to and use technology such as computers and mobile phones. These patients expressed interest in a portal that would provide them with an opportunity to network with others with myotonic dystrophy and to access information about the disease.

A 9-year follow-up study of the natural progression of upper limb performance in myotonic dystrophy type 1: A similar decline for phenotypes but not for gender

This study aimed to document and compare the decline of upper limb performance among adults with myotonic dystrophy type 1 according to phenotype and gender. A longitudinal descriptive design compared upper limb performance at baseline and follow-up of 70 women and 38 men with the late-onset or adult phenotypes. Grip strength and pinch strength as well as gross dexterity and fine dexterity were assessed. All four performance measures decreased significantly (p <0.001). The decline over time was similar for individuals with the late-onset and adult-onset phenotypes, but differed according to gender. For late-onset and adult-onset phenotypes respectively, women lost less grip strength than men: 0.4 and minus 0.8 kg (2.0% and -9.4%) in women vs. minus 7.4 and minus 3.1 kg (-19.2% and -30.7%) in men. A similar situation was found for gross dexterity: minus 3.0 and minus 3.2 blocks (-4.6% and -5.9%) in women vs. minus 12.4 and minus 8.7 blocks (-19.4% and -16.6%) in men. Pinch gauge had the smallest standard deviations and was one of the only measurement tools with significant detectable changes in relation to the standard error of measurement. Given these results, health professionals and researchers should consider phenotype and gender differently when planning health services or future studies. Indeed, as their upper limb strength and dexterity differed, even if their decline was similar, the phenotypes should not be pooled. Finally, the use of the pinch gauge to assess long-term change in upper limb ability seems preferable to the three other measurements.

Further evidence for the reliability and validity of the Fatigue and Daytime Sleepiness Scale

BACKGROUND

Myotonic dystrophy type 1 (DM1) is an inherited neuromuscular disease causing, among other symptoms, fatigue and excessive daytime sleepiness, which are frequently undifferentiated by patients and/or clinicians. The Fatigue and Daytime Sleepiness Scale (FDSS) has been devised to measure these two overlapping symptoms as a single clinical entity.

OBJECTIVE

To further examine the reliability and the construct validity of the FDSS in patients with DM1.

METHODS

The scale was administered to 48 DM1 patients on two occasions at a 2week-interval. Intra-rater reliability and internal consistency were established by calculating the intraclass correlation coefficient (ICC) and Cronbach's alpha, respectively. Construct validity was assessed by using the known-group method. More precisely, the mean FDSS score of patients with and without subjective complaints of fatigue and/or sleepiness was compared.

RESULTS

The FDSS showed good intra-rater reliability (ICC=0.83) and acceptable internal consistency (Cronbach's alpha =0.6). Also, the FDSS was able to distinguish between patients who had fatigue and sleepiness complaints from those who did not (mean FDSS score of 10.6 vs 8.0, p=0.01), suggesting good construct validity.

CONCLUSION

Overall, the present study supports the continued use of the FDSS as a reliable and valid instrument to measure fatigue and daytime sleepiness in patients with DM1 for either clinical or research purposes.

The UK Myotonic Dystrophy Patient Registry: facilitating and accelerating clinical research

Myotonic dystrophy type 1 (DM1) is the most frequent muscular dystrophy worldwide with complex, multi-systemic, and progressively worsening symptoms. There is currently no treatment for this inherited disorder and research can be challenging due to the rarity and variability of the disease. The UK Myotonic Dystrophy Patient Registry is a patient self-enrolling online database collecting clinical and genetic information. For this cross-sectional “snapshot” analysis, 556 patients with a confirmed diagnosis of DM1 registered between May 2012 and July 2016 were included. An almost even distribution was seen between genders and a broad range of ages was present from 8 months to 78 years, with the largest proportion between 30 and 59 years. The two most frequent symptoms were fatigue and myotonia, reported by 79 and 78% of patients, respectively. The severity of myotonia correlated with the severity of fatigue as well as mobility impairment, and dysphagia occurred mostly in patients also reporting myotonia. Men reported significantly more frequent severe myotonia, whereas severe fatigue was more frequently reported by women. Cardiac abnormalities were diagnosed in 48% of patients and more than one-third of them needed a cardiac implant. Fifteen percent of patients used a non-invasive ventilation and cataracts were removed in 26% of patients, 65% of which before the age of 50 years. The registry’s primary aim was to facilitate and accelerate clinical research. However, these data also allow us to formulate questions for hypothesis-driven research that may lead to improvements in care and treatment.

Participation restriction in childhood phenotype of myotonic dystrophy type 1: a systematic retrospective chart review

AIM

Myotonic dystrophy type 1 (DM1), a neuromuscular disorder, is divided into four clinical phenotypes: congenital; childhood; adult-onset, and late-onset. Publications about the childhood phenotype, especially the long-term outcome, are scarce. The aims of this study were to assess and describe participation outcomes in adults with the childhood phenotype.

METHOD

A retrospective chart methodology. Data were extracted from health records for 63 adults with childhood DM1 (32 males, 31 females; mean age 34y, standard deviation [SD] 11y 6mo; range 18-54y) who had attended the Saguenay Neuromuscular Clinic, Canada.

RESULTS

Thirty-four adults (54%) lived with their parents or in foster homes, and most patients needed services or help to live independently. A significant proportion (22%) were isolated in regard to friendship. Very few adults had children, although 33% lived with a spouse. The majority of patients (86%) relied on social security and only one person was currently working. Financial responsibilities were often an issue and 13 (21%) were under legal guardianship.

INTERPRETATION

This study showed that patients with the childhood phenotype present a guarded prognosis regarding long-term social participation. These participation restrictions could be related to behavioural, cognitive, and social stigma problems in childhood. This study illustrates the absolute necessity to pursue an interdisciplinary follow-up of these patients when they are reaching adulthood.

Patient-Centered Therapy Development for Myotonic Dystrophy: Report of the Myotonic Dystrophy Foundation-Sponsored Workshop

Myotonic dystrophy (DM) is an autosomal dominant, repeat expansion, progressive disorder with no drug therapies. Consequently, to better define a regulatory pathway in anticipation of new treatment strategies under investigation, the Myotonic Dystrophy Foundation convened a workshop entitled "Patient-Centered Therapy Development for Myotonic Dystrophy" in September 2015. Participants included representatives from academia, industry, the patient community, the National Institutes of Health (NIH) and the Food and Drug Administration (FDA). Presenters described the symptom burden of the disease, and existing data on DM biomarkers, endpoints, natural history, and benefit-risk considerations. FDA participants helped clarify the regulatory requirements for new drug treatment approvals and DM-specific issues such as variability, slow progression, and low prevalence. Workshop attendees gained a better understanding of DM and the current status of existing data and tools to support therapeutic drug research and development.

Lower limb muscle strength impairment in late-onset and adult myotonic dystrophy type 1 phenotypes

INTRODUCTION

Lower limb strength has never been characterized separately for late-onset and adult myotonic dystrophy type 1 (DM1) phenotypes.

METHODS

The purpose of this study was to: (1) describe and compare lower limb strength between the 2 DM1 phenotypes; and (2) compare the impairment profiles obtained from 2 assessment methods [manual (MMT) and quantitative (QMT) muscle testing] among 107 patients.

RESULTS

Both MMT and QMT showed more pronounced weakness in the adult phenotype. In the late-onset phenotype, although MMT showed normal strength, QMT revealed a loss of 11.7%-20.4%. Participants with grade 1 or 2 on the Muscle Impairment Rating Scale had weakness detected using QMT, which suggests earlier muscle impairment than MMT alone would suggest.

CONCLUSIONS

To avoid muscle wasting, physical activity recommendations should be made for the late-onset phenotype and in the early stages of the disease for the adult phenotype. MMT is not recommended for use in clinical trials. Muscle Nerve 56: 57-63, 2017.

Myotonic Dystrophy and Huntington's Disease Care: "We Like to Think We're Making a Difference"

BACKGROUND

Patient-centered care for individuals with myotonic dystrophy (DM1) and Huntington's disease (HD)-chronic, progressive, and life-limiting neurological conditions-may be challenged by patients' cognitive and behavioral impairments. However, no research has explored health care providers' (HCPs') perspectives about patient-centered care provision for these patients along their disease trajectory.

METHODS

Constructivist grounded theory informed the iterative data collection and analysis process. Eleven DM1 or HD HCPs participated in semistructured interviews, and three stages of coding were used to analyze their interview transcripts. Codes were collapsed into themes and categories.

RESULTS

Three categories including an evolving care approach, fluid roles, and making a difference were identified. Participants described that their clinical care approach evolved depending on the patient's disease stage and caregivers' degree of involvement. HCPs described that their main goal was to provide hope to patients and caregivers through medical management, crisis prevention, support, and advocacy. Despite the lack of curative treatments, HCPs perceived that patients benefited from ongoing clinical care provided by proactive clinicians.

CONCLUSIONS

Providing care for individuals with DM1 and HD is a balancing act. HCPs must strike a balance between (1) the frustrations and rewards of patient-centered care provision, (2) addressing symptoms and preventing and managing crises while focusing on patients' and caregivers' quality of life concerns, and (3) advocating for patients while addressing caregivers' needs. This raises important questions: Is patient-centered care possible for patients with cognitive decline? Does chronic neurological care need to evolve to better address patients' and caregivers' complex needs?

Using the refined ICF Linking Rules to compare the content of existing instruments and assessments: a systematic review and exemplary analysis of instruments measuring participation

BACKGROUND

Existing instruments measuring participation may vary with respect to various aspects. This study aimed to examine the comparability of existing instruments measuring participation based on the International Classification of Functioning, Disability and Health (ICF) by considering aspects of content, the perspective adopted and the categorization of response options.

METHODS

A systematic literature review was conducted to identify instruments that have been commonly used to measure participation. Concepts of identified instruments were then linked to the ICF following the refined ICF Linking Rules. Aspects of content, perspective adopted and categorization of response options were documented.

RESULTS

Out of 315 instruments identified in the full-text screening, 41 instruments were included. Concepts of six instruments were linked entirely to the ICF component Activities and Participation; of 10 instruments still 80% of their concepts. A descriptive perspective was adopted in most items across instruments (75%), mostly in combination with an intensity rating. An appraisal perspective was found in 18% and questions from a need or dependency perspective were least frequent (7%).

CONCLUSION

Accounting for aspects of content, perspective and categorization of responses in the linking of instruments to the ICF provides detailed information for the comparison of instruments and guidance on narrowing down the choices of suitable instruments from a content point of view. Implications for Rehabilitation For clinicians and researchers who need to identify a specific instrument for a given purpose, the findings of this review can serve as a screening tool for instruments measuring participation in terms of the following: • Their content covered based on the ICF. • The perspective adopted in the instrument (e.g., descriptive, need/dependency or appraisal). • The categorization of their response options (e.g., intensity or frequency).

Why stay home? Temporal association of pain, fatigue and depression with being at home

BACKGROUND

Community participation is important to most people with disabilities despite the fact that common secondary conditions like pain, fatigue and depression may increase the difficulty of leaving home. Despite decades of research on these secondary conditions, little is known about how they are associated with being at home.

OBJECTIVE

We used Ecological Momentary Assessment data to examine within subject fluctuation in these secondary conditions to examine their effect on the likelihood that participants remain at or return home.

METHODS

Participants (n = 139) were recruited from a population based sampling frame to complete an Ecological Momentary Assessment that queried their location and experience with secondary conditions six times a day for two weeks.

RESULTS

Between subjects secondary condition ratings averaged across time periods indicated that pain and depression were associated with the share of measurement periods that respondents reported being at home. Within subject results indicated that a standard unit increase in pain, fatigue and depression was associated with being home one to two days later. Within day results indicated that increases in pain and fatigue were associated with increased likelihood of being home later, but increases in depression were associated with lower likelihood of being home later.

CONCLUSION

These results suggest there may be a complicated relationship among these secondary conditions and community participation with effects observed both across and within days. One interpretation suggests that secondary condition severity is tempered by adjusting participation. These results may have implications for intervening on these secondary conditions.

Prevalence and correlates of apathy in myotonic dystrophy type 1

Background

Apathy in DM1 has long been acknowledged in clinical practice. However, a major drawback is that the concept has been only sparsely explored in previous specific studies. This study aimed to determine the prevalence of apathy in myotonic dystrophy (DM1), to compare it with facioscapulohumeral dystrophy (FSHD) patients and normal healthy controls, and explore its relationship to psychopathological features and cognitive function.

Methods

Levels of apathy in 38 DM1 patients with adult phenotypes were compared with 19 patients with FSHD and 20 matched controls. Patient participants were consecutively recruited, regarding their interdisciplinary annual evaluation at the neuromuscular pathology reference center (Institute of Myology, Paris, France), within an 18-month period. Additional measurements included motor disability, fatigue, depression, anxiety, and cognitive abilities. Inter-group comparisons were performed using non-parametric Kruskal-Wallis tests and Mann–Whitney U Tests. Intra-group comparisons were carried out with the Wilcoxon Signed rank and Friedman tests. Also, Spearman’s correlations were used to assess the strength of linear relationships between pairs of variables. The significance level was set at 0.05.

Results

Global score of apathy was significantly higher in DM1 patients than in FSHD patients (p < 0.01) and in controls (p < 0.001). Sixteen of 38 DM1 patients (39.5 %) met the criterion for apathy, contrasting with only 4 of the 19 (21.1 %) FSHD patients. No control subject was apathetic. Moreover, apathy in DM1 patients was negatively correlated to MMSE (r = −.46, p < .05) and Stroop Word (r = −.55, p < .01) scores, but not with age, educational level, disease duration, CTG repeats, motor functional disability, fatigue, depression, and anxiety.

Conclusions

Apathy is a frequent symptom in DM1 (almost 40 %). It is more prevalent than in a similarly disabled group of patients with FSHD and in controls. Results also show that apathy in DM1 is independent of the psychopathological domain, fatigue, age, and motor disability, but associated to general cognitive status. These results altogether could suggest a central cause for apathy in DM1 rather than an adjustment process to cope with the progressive and debilitating nature of the disease. Data emphasize the importance to evaluate this symptom in routine clinical management of DM1 patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s12883-015-0401-6) contains supplementary material, which is available to authorized users.

Variability of multisystemic features in myotonic dystrophy type 1--lessons from Serbian registry

BACKGROUND

Myotonic dystrophy type 1 (DM1) is a rare disease. Creating registry for such a disease is of outstanding importance since it provides us with a full spectrum of the disorder.

AIM

To assess variability of different multisystemic features in a large cohort of patients with DM1.

PATIENTS AND METHOD

Data from the Serbian registry for myotonic dystrophies were used in the study. Final number of included DM1 subjects was 275.

RESULTS

Registry included 53.8% of male patients. Age at enrollment was 47.2 ± 9.9 years, mean disease duration 20.4 ± 9.9 years, and mean CTG repeats number 598.3 ± 269.8.Progression of muscle weakness was pretty slow, slower in proximal than distal muscles, and slower in arms than in legs. Severe ECG abnormality was found in 25.0% of patients and pacemaker was implanted in 9.5%. Lens opacities were observed in 83.5% of DM1 patients and 35.3% had ocular hypotony. Metabolic disturbances were very common, while 19.5% of patients had hypokalemia and 37.8% hypochloremia. Sterility was found in 20.5% of males and 4.1% of females. Cholelithiasis was found in 36.4% of patients and constipation in 29.9%.

CONCLUSIONS

We defined the most common characteristics of our DM1 patients and observed some treatable symptoms that have been neglected previously. Certain findings deserve further investigations in terms of their causes and consequences. Besides this, presented data analysis directs us to make further improvements of the registry.