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Introduction/aims: Improved functional outcome measures in amyotrophic lateral sclerosis (ALS) would aid ALS trial design and help hasten drug discovery. We evaluate the longitudinal performance of the Rasch-Built Overall Amyotrophic Lateral Sclerosis Disability Scale (ROADS) compared to the Amyotrophic Lateral Sclerosis Functional Rating Scale Revised for Self-Entry (ALSFRS-RSE) as patient reported outcomes of functional status in people with ALS.Methods: Participants completed the ROADS and the ALSFRS-RSE questionnaires at baseline, 3-, 6-, and 12- mo using Research Electronic Data Capture as part of a prospective, longitudinal, remote, online survey study of fatigue in ALS from 9/2020 to 12/2021. The scales were compared cross-sectionally (at baseline) and longitudinally. Correlation coefficients, coefficients of variation, and descriptive statistics were assessed.Results: A total of 182 adults with ALS consented to the study. This volunteer sample was comprised of predominantly White, non-Hispanic, non-smoking participants. Consented participant survey completion was approximately 90% at baseline and greater than 40% at 12 mo. The ALSFRS-RSE and the ROADS had high, significant agreement at 3 and 6 mo by Cohen's kappa ≥71% (p < 0.001); the number of functional increases or plateaus on the two scales were not significantly different; and the coefficient of variation of functional decline was similar at the 6-month mark, though higher for the ROADS at 3 mo and lower at 12 mo.Discussion: Although the ROADS performed similarly to the ALSFRS-RSE in an observational cohort, it has psychometric advantages, such as Rasch-modeling and unidimensionality. It merits further investigation as a patient reported outcome of overall disability and efficacy outcome measure in ALS trials. [ABSTRACT FROM AUTHOR]

Introduction/aims: Most mouse models of muscular dystrophy (MD) show mild phenotypes, which limits the translatability of experimental therapies to patients. A growing body of evidence suggests that MD is accompanied by metabolic abnormalities that could potentially exacerbate the primary muscle wasting process. Since thermoneutral (TN) housing of mice (~30°C) has been shown to affect many metabolic parameters, particularly when combined with a Western diet (WD), our aim was to determine whether the combination of TN and WD exacerbates muscle wasting in dysferlin-deficient BLAJ mice, a common model of limb-girdle MD type 2b (LGMD2b).Methods: The 2-mo-old wild-type (WT) and BLAJ mice were housed at TN or room temperature (RT) and fed a WD or regular chow for 9 mo. Ambulatory function, muscle histology, and protein immunoblots of skeletal muscle were assessed.Results: BLAJ mice at RT and fed a chow diet showed normal ambulation function similar to WT mice, whereas 90% of BLAJ mice under WD and TN combination showed ambulatory dysfunction (p < 0.001), and an up to 4.1-fold increase in quadriceps and gastrocnemius fat infiltration. Western blotting revealed decreased autophagy marker microtubules-associated protein 1 light chain 3-B (LC3BII/LC3BI) ratio and up-regulation of protein kinase B/AKT and ribosomal protein S6 phosphorylation, suggesting inefficient cellular debris and protein clearance in TN BLAJ mice fed a WD. Male and female BLAJ mice under TN and WD combination showed heterogenous fibro-fatty infiltrate composition.Discussion: TN and WD combination exacerbates rodent LGMD2b without affecting WT mice. This improves rodent modeling of human MD and helps elucidate how metabolic abnormalities may play a causal role in muscle wasting. [ABSTRACT FROM AUTHOR]

Introduction/aims: We assessed the classification performance of machine learning (ML) using multifrequency electrical impedance myography (EIM) values to improve upon diagnostic outcomes as compared to those based on a single EIM value.Methods: EIM data was obtained from unilateral excised gastrocnemius in eighty diseased mice (26 D2-mdx, Duchenne muscular dystrophy model, 39 SOD1G93A ALS model, and 15 db/db, a model of obesity-induced muscle atrophy) and 33 wild-type (WT) animals. We assessed the classification performance of a ML random forest algorithm incorporating all the data (multifrequency resistance, reactance and phase values) comparing it to the 50 kHz phase value alone.Results: ML outperformed the 50 kHz analysis as based on receiver-operating characteristic curves and measurement of the area under the curve (AUC). For example, comparing all diseases together versus WT from the test set outputs, the AUC was 0.52 for 50 kHz phase, but was 0.94 for the ML model. Similarly, when comparing ALS versus WT, the AUCs were 0.79 for 50 kHz phase and 0.99 for ML.Discussion: Multifrequency EIM using ML improves upon classification compared to that achieved with a single-frequency value. ML approaches should be considered in all future basic and clinical diagnostic applications of EIM. [ABSTRACT FROM AUTHOR]

Introduction/Aims: Neuralgic amyotrophy (NA) is a multifocal neuropathy involving the nerves of the upper extremity, limiting functional capability and reducing range of motion. The reachable workspace (RWS) is a computerized three‐dimensinal analysis system that evaluates the relative surface area (RSA) of an individual's arm reachability and has shown utility in several neuromuscular disorders. The aims of this study were to examine the ability of the RWS to quantitatively detect limitations in upper extremity active range of motion in patients with NA, and correlate these with other upper extremity functional outcome measures. Methods: Forty‐seven patients with NA and 25 healthy age‐ and sex‐matched controls were measured with the RWS. Study participants' RSAs were correlated with scores on the Shoulder Rating Questionnaire (SRQ), the Disabilities of Arm Shoulder and Hand (DASH) questionnaire, and upper extremity strength measurements using hand‐held dynamometry. Results: Patients with NA showed significantly lower values in the affected arm for all quadrants (except for the ipsilateral lower quadrant) and total RSA compared with controls (P < 0.001). We found moderate correlations between the reachable workspace, the DASH questionnaire result (r = −0.415), and serratus anterior muscle strength (r = 0.414). Discussion: RWS is able to detect limitations in active range of motion of the affected arm in patients with NA, and is moderately correlated with upper extremity functional measures. RWS can demonstrate impairment of the affected upper extremity in NA and it has potential as a clinical outcome measure. [ABSTRACT FROM AUTHOR]

Introduction/Aims: It is important to quantify the amount of crossover innervation from the anterior interosseous nerve (AIN) through Martin‐Gruber anastomosis (MGA) particularly in patients with high ulnar nerve injury who undergo nerve transfer surgery. The objective of this study is to describe a novel electrophysiological method for quantifying innervation from the AIN that can be done using conventional nerve conduction study setup and commonly available software for analysis. Methods: Seven subjects with MGA and nine patients who had undergone AIN to ulnar nerve transfer underwent conventional motor nerve conduction studies. Recording was done over the hypothenar and first dorsal interosseous muscles while stimulating the median and ulnar nerves at the wrist and elbow. Datapoint‐by‐datapoint subtraction of the compound muscle action potentials evoked at the elbow and wrist was performed after they had been onset‐aligned. The results were compared to the collision technique and innervation ratio method. Result: Results from the digital subtraction method were highly correlated with the collision technique (r = 0.96, p < 0.05). In contrast, its correlation with the innervation ratio method is substantially lower. Discussion: In comparison to previously described techniques, the digital subtraction method has a number of practical advantages. It uses conventional nerve conduction study setup, and the added step of digital alignment and subtraction can be done through commonly available software. With the increasing use of nerve transfer surgery in severe high ulnar nerve injury, this could be a useful method to identify the presence of MGA prior to surgery and for evaluating nerve recovery following surgery. [ABSTRACT FROM AUTHOR]

Introduction/Aims: Spinal muscular atrophy (SMA) treatment may increase survival and improve physical function among adolescents and young adults. Validated patient‐reported outcome measures are needed to understand which treatment benefits are clinically meaningful and to develop targeted resources for this population. To date, use of the SMA Health Index (SMA‐HI) in pediatric and young adult populations has been limited. Here, we report results from a survey of adolescents and young adults with SMA to quantifiably understand individuals' perceptions of disease burden. Methods: Participants aged 12–25 y with a self‐reported diagnosis of SMA completed an online survey containing demographic questions and the SMA‐HI, a patient‐reported outcome measure that assesses individuals' perceptions of disease burden in 15 symptomatic areas. Results: Eighty‐eight participants completed the survey. Total SMA‐HI scores and SMA‐HI subscale scores including shoulder and arm function; back, chest, and abdominal function; activity participation; hand and finger strength; swallowing function; gastrointestinal function; respiratory function; mobility and ambulation, and total disease burden were significantly higher (greater disease burden) in patients with poorer motor function and severe SMA. SMA‐HI total and subscale scores were generally lower in adolescents (12–17 y old) versus adults (18–25 y old), suggesting a possible progression of symptomatic disease burden over time. Discussion: This study demonstrates the utility of the SMA‐HI for measuring clinically relevant disease burden in adolescents and young adults with SMA. This study demonstrates how disease burden varies by age, SMA type, and other demographics. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) is the most common adult‐onset motor neuron disorder characterized by progressive degeneration of cortical, bulbar, and spinal motor neurons. When a patient presents with a progressive upper and/or lower motor syndrome, clinicians must pay particular attention to any atypical features in the history and/or clinical examination suggesting an alternate diagnosis, as up to 10% percent of patients initially diagnosed with ALS have a mimic of ALS. ALS is a clinical diagnosis and requires the exclusion of other disorders that may have similar presentations but a more favorable prognosis or an effective therapy. Because there is currently no specific diagnostic biomarker that is sensitive or specific for ALS, understanding the spectrum of clinical presentations of ALS and its mimics is paramount. While true mimics of ALS are rare, the clinician must correctly identify these disorders to avoid the misdiagnosis of ALS and to initiate effective treatment where available. [ABSTRACT FROM AUTHOR]

Introduction/Aims: Nephropathic cystinosis is a lysosomal storage disorder with known myopathic features, including dysphagia. Evaluation of oropharyngeal swallowing physiology can be standardized using the Modified Barium Swallow Impairment Profile (MBSImP), a validated assessment tool used to analyze and rate swallowing across 17 distinct physiologic domains. Our objective was to better characterize swallowing impairments in nephropathic cystinosis using MBSImP analysis. Methods: We retrospectively evaluated 40 video fluoroscopic swallowing studies performed at two time points over 1 y in patients with nephropathic cystinosis with various levels of oral and pharyngeal stage dysphagia. Patients completed two self‐administered dysphagia outcome measures (the M. D. Anderson Dysphagia Inventory [MDADI] and the 10‐item Eating Assessment Tool [EAT‐10]). Results: We demonstrated oral stage and pharyngeal stage dysphagia across domains that impacted bolus control, transit, and clearance through both the oral cavity and pharyngeal lumen. Also captured were deficits related to onset and completeness of laryngeal closure that impact airway protection during swallow. There were significant correlations between pharyngeal total score and EAT‐10 (r = 0.5, p < 0.001) and between oral total score and EAT‐10 (r = 0.7, p < 0.001), MDADI‐e (r = −0.6, p < 0.001), MDADI‐p (r = −0.5, p < 0.001) and MDADI‐c (r = −0.6, p < 0.001). There were no differences in oral or pharyngeal total scores across the 1‐y time span. Discussion: This study identifies oral and pharyngeal stage dysphagia as crucial to patients with nephropathic cystinosis and paves the path for future studies of treatment targets. [ABSTRACT FROM AUTHOR]

This monograph contains descriptions of the single fiber electromyography (SFEMG) method and of the more recently implemented method of recording jitter with concentric needle electrodes (CNEs). SFEMG records action potentials from single muscle fibers (SFAPs), which permits measuring fiber density (FD), a sensitive measure of reinnervation, and jitter, a sensitive measure of abnormal neuromuscular transmission (NMT). With voluntary activation, jitter is measured between two SFAPs with acceptable amplitude and rise time. With activation by axon stimulation, jitter is measured between the stimulus and individual SFAPs. Pitfalls due to unstable triggers and inconstant firing rates during voluntary activation and subliminal stimulation during axon stimulation should be identified and avoided. In CNE recordings, spikes with shoulders or rising phases that are not parallel are produced by summation of SFAPS; these should be excluded and reference values for CNE jitter should be used. CNE and SFEMG have similar and very high sensitivity in detecting increased jitter, as in myasthenia gravis and other myasthenic conditions. However, jitter is also seen in ongoing reinnervation and some myopathic conditions. With SFEMG, these can be identified by increased FD; however, FD cannot be measured with CNE, and conventional electromyography should be performed in muscles with increased jitter to detect neurogenic or myogenic abnormalities. Jitter is abnormal after injections of botulinum toxin, even in muscles remote from the injection site, and can persist for 6 mo or more. This can complicate the detection or exclusion of abnormal NMT. [ABSTRACT FROM AUTHOR]

Introduction/Aims: The aim of this study was to describe a new method for studying the supraclavicular nerve (SCN) conduction and to report four cases with SCN lesions. Methods: The SCN was antidromically recorded with a pair of self‐adhesive electrodes located in the middle of the clavicle. Stimulation (<5 mA) was delivered 7 cm proximally with a bar electrode. To facilitate recording, it was explained to the participant that they would feel a very faint electrical sensation locally and an electrical tingle upward (ear) or downward (shoulder/clavicle). Each participant was asked to say when the tingling moved downward. Results: In normal subjects, median values were 16 μV (range: 9–33) for sensory nerve action potential (SNAP) amplitude; 1.2 ms (range: 1–1.5) for onset latency; and 1.25 (range: 1–1.7) for side‐to‐side amplitude ratio. In the four patients, the SCN SNAP was absent on the pathological side and normal on the healthy side. All four patients complained of unilateral neuropathic hypoesthesia on the anterior aspect of the neck, chest, and shoulder that occurred after radical neck surgery for thyroid or larynx cancer (x3) and first rib resection (x1). Discussion: A comparison with previous reports shows that this simple method provides similar or highest SNAP amplitudes. SCN lesions are rare, and rarely referred for electrodiagnosis, and often overlooked. However, the SCN conduction study, which causes very slight inconvenience (low‐intensity stimulation), allows a better understanding of the origin of the complaints and permits the patient to benefit of more suitable treatment. [ABSTRACT FROM AUTHOR]

Introduction/Aims: Pompe disease is a progressive myopathy that combines motor, respiratory, and cardiac impairments. The 6‐min walk test is the gold standard for assessing disease severity at the motor level. The objective of this study was to better determine the parameters that influence the total distance covered in patients with Pompe disease. Methods: We performed a retrospective review of 15 patients with late‐onset Pompe disease who were followed regularly at a single referral center. Logistic regression was used to investigate the links between motor, respiratory and cardiac variables and 6‐min walk test performance. Results: When considering baseline clinical and demographic variables, a seven‐step backward elimination regression analysis yielded a model with two predictors (age and the use of an assistive device) that explained 85.5% of the variance. When considering the cardiorespiratory variables monitored during gait, a three‐step backward elimination regression analysis showed that two predictors (heart rate recovery and the baseline partial pressure of carbon dioxide) explained 42.2% of the variance. Discussion: Our results highlighted the importance of respiratory and cardiac adaptation during exercise (along with motor ability) during the 6‐min walk test in patients with Pompe disease. Further studies of larger cohorts are necessary to validate the model, which might enable investigators to determine whether intra‐individual fluctuations in 6‐min walk test performance are related to physiological parameters and/or to other variables such as the patient′s level of motivation during the test. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

See article on pages E10 in this issue. [ABSTRACT FROM AUTHOR]

Introduction/Aims: There is debate about whether and to what extent either respiratory or cardiac dysfunction occurs in patients with dysferlinopathy. This study aimed to establish definitively whether dysfunction in either system is part of the dysferlinopathy phenotype. Methods: As part of the Jain Foundation's International Clinical Outcome Study (COS) for dysferlinopathy, objective measures of respiratory and cardiac function were collected twice, with a 3‐y interval between tests, in 188 genetically confirmed patients aged 11–86 y (53% female). Measures included forced vital capacity (FVC), electrocardiogram (ECG), and echocardiogram (echo). Results: Mean FVC was 90% predicted at baseline, decreasing to 88% at year 3. FVC was less than 80% predicted in 44 patients (24%) at baseline and 48 patients (30%) by year 3, including ambulant participants. ECGs showed P‐wave abnormalities indicative of delayed trans‐atrial conduction in 58% of patients at baseline, representing a risk for developing atrial flutter or fibrillation. The prevalence of impaired left ventricular function or hypertrophy was comparable to that in the general population. Discussion: These results demonstrate clinically significant respiratory impairment and abnormal atrial conduction in some patients with dysferlinopathy. Therefore, we recommend that annual or biannual follow‐up should include FVC measurement, enquiry about arrhythmia symptoms and peripheral pulse palpation to assess cardiac rhythm. However, periodic specialist cardiac review is probably not warranted unless prompted by symptoms or abnormal pulse findings. [ABSTRACT FROM AUTHOR]

Introduction/Aims: Electromyography (EMG) can provide valuable insights into the pathophysiology of oropharyngeal muscles in various disease states, but the invasive nature of the conventional needle EMG (nEMG) has its limitations in this setting. We aimed to examine the inter‐rater reliability (IRR) of a novel transmembranous EMG (tmEMG) sensor as a non‐invasive technique for assessment of oral cavity and oropharyngeal muscles for neuromuscular pathology. Methods: The study was a prospective, cohort, pilot study with blinded data analysis in healthy participants (n = 6), patients with moderate to severe obstructive sleep apnea (OSA) (n = 5) and bulbar amyotrophic lateral sclerosis (ALS) (n = 5). Each patient underwent sampling from bilateral palatoglossus (PG) and genioglossus (GG), using both tmEMG and nEMG. IRR was expressed as percentage agreement and prevalence‐adjusted bias‐adjusted kappa coefficient (PABAK). Results: Substantial IRR was found for participants with ALS (81.6%, PABAK 0.63) and OSA (78.8%, PABAK 0.61), and in healthy participants (87.1%, PABAK 0.74). A better IRR was seen with tmEMG (95.7%, PABAK 0.92) than with nEMG (73.9%, PABAK 0.48) for healthy participants and also for those with OSA. Studies from GG had higher IRR than PG. Only one participant had a minor adverse event (sore throat). Discussion: The current study shows that analysis of PG and GG in both healthy and disease states using tmEMG has high IRR compared with nEMG analysis. Further validation studies can be undertaken to test its utility in analysis of oral cavity and oropharyngeal muscles. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) remains a rapidly progressive fatal degenerative disease of motor neurons for which there are few interventions to slow disease progression or improve quality of life. A diaphragm pacing system was approved by the U.S. Food and Drug Administration in September 2011 for ALS under a Humanitarian Device Exemption. News of this approval has been met with a combination of excitement and uncertainty by members of the ALS community. We review the currently available data on the diaphragm pacing system and its use in ALS. Diaphragm pacing appears to be reasonably safe in carefully selected patients, but flaws in the reporting on it thus far preclude conclusions regarding efficacy. Further study is needed. Muscle Nerve 46: 1-8, 2012 [ABSTRACT FROM AUTHOR]

See article on pages 679–685 in this issue. [ABSTRACT FROM AUTHOR]

Introduction: Non-dystrophic myotonia (NDM) is caused by mutations in muscle chloride and sodium channels. Currently, there is no standardized instrument for documenting symptom frequency and severity in NDM. Methods: Subjects used an automated, interactive, telephone-based voice response diary (IVR) to record frequency and severity of stiffness, weakness, pain, and tiredness once a week for 8 weeks, after their baseline visits. Results: We describe the IVR and report data on 76 subjects for a total of 385 person-weeks. Overall there were 5.1 calls per subject. Forty-eight subjects called in 5 or more times, and 14 called in 8 times. Stiffness was both the most frequent and severe symptom. Warm-up and handgrip myotonia were associated with higher severity scores for stiffness. Conclusions: IVR is a convenient technology to allow patient reporting of repeated and real-time symptom frequency and severity, and it is presently being used in a trial of mexiletine in NDM. Muscle Nerve 44: 30-35, 2011 [ABSTRACT FROM AUTHOR]

The article presents updates on the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM) as of May 2011. According to Dr. Charles Jablecki, EDX physicians must focus on the preparing quality EDX reports with emphasis on quality patient care. AANEM aims to help physicians enhance the quality of their reports through its report template based on its educational paper titled "Reporting the Results of Needle EMG and Nerve Conduction Studies." AANEM will have its 58th annual meeting in San Francisco, California in September 2011.

See article on pages 633–637 in this issue. [ABSTRACT FROM AUTHOR]

Introduction/Aims Scoliosis is a common comorbidity among individuals diagnosed with a dystrophinopathy. We examined associations between clinical predictors and scoliosis in childhood‐onset dystrophinopathy. Methods: The progression and treatment of scoliosis were obtained from data collected by the US population‐based Muscular Dystrophy Surveillance, Tracking, and Research Network. Associations between loss of independent ambulation (LoA) and corticosteroid use and scoliosis outcomes (ages at or exceeding Cobb angle thresholds [10°, 20°, 30°]; surgery) were estimated using Kaplan–Meier curve estimation and extended Cox regression modeling. Results: We analyzed curvature data for 513 of 1054 individuals ascertained. Overall, approximately one‐half had at least one radiograph and one‐quarter had a curvature of at least 20°. The average maximum curvature was 25.0° (SD = 21.5°) among all individuals and 42.8° (SD = 18.8°) among those recommended for surgery. Higher adjusted hazards ratio of curvature (aHR(curvature) [95% confidence interval]) were found among individuals with LoA compared to those without LoA (aHR(10) = 6.2 [4.4, 8.7], aHR(20) = 15.3 [7.4, 31.7], aHR(30) = 31.6 [7.7, 128.9]), among individuals who did not use corticosteroids compared to those who did (aHR(10) = 1.2 [0.9, 1.7], aHR(20) = 1.8 [1.1, 2.7], aHR(30) = 2.3 [1.3, 4.0]), and among non‐ambulatory individuals who used corticosteroids after LoA compared to those who did not (aHR(10) = 1.8 [1.2, 2.8], aHR(20) = 1.6 [1.0, 2.6], aHR(30) = 3.6 [1.6, 7.9]). Scoliosis surgery among individuals with LoA who did not use corticosteroids was more than double compared to those who used (aHR = 2.3 [1.3, 4.2]). Discussion Our retrospective observational study suggests corticosteroids may delay spinal curvature progression and need for scoliosis surgery. Continuing corticosteroids after LoA also showed potential benefits of delaying curvature progression, additional studies are needed to confirm this finding or address the magnitude of benefit. [ABSTRACT FROM AUTHOR]

Introduction/Aims: Data regarding the comparative effectiveness of myasthenia gravis (MG) treatments is not available. We used patient input to identify a patient‐centered outcome measure (PCOM) for PROMISE‐MG, a comparative effectiveness trial of MG treatments. Methods: First, a questionnaire survey was administered to 58 people with MG at the patient meeting of the Myasthenia Gravis Foundation of America (MGFA), evaluating the impact of MG‐related symptoms and MG treatments on patients' lives. Second, an online focus group of 13 patients with MG was conducted. Third, a potential outcome measure was selected. Fourth, the selected PCOM was evaluated by patients to assess how completely and accurately it captured their experiences with MG. Results: The patient survey showed that limb weakness had the most impact on patients' lives. Weight gain, mood swings, insomnia, and diarrhea were the most bothersome treatment side effects. Avoiding hospitalization was very important. Focus group participants reported fatigue as one of the most bothersome symptoms and differentiated it from myasthenic weakness. They defined an ideal treatment as having minimal or no side effects and an 80% improvement in symptoms. Discussion Based on patient input, the 15‐item Myasthenia Gravis Quality of Life—Revised (MG‐QOL15R) scale, a validated patient‐reported outcome measure (PRO), was selected as the primary PCOM for PROMISE‐MG. Avoiding hospitalization and having minimal to no treatment adverse effects were selected as additional outcome measures. The patient‐centeredness of a PRO depends on the context of a study: PROs should be evaluated for appropriateness as a PCOM for every study. [ABSTRACT FROM AUTHOR]

Introduction/Aims: Duchenne and Becker muscular dystrophies (DBMD) are X‐linked neuromuscular disorders characterized by progressive muscle weakness, leading to decreased mobility and multisystem complications. We estimate productivity costs attributable to time spent by a parent caring for a male child under the age of 18 y with DBMD, with particular focus on female caregivers of boys with Duchenne muscular dystrophy (DMD) who have already lost ambulation. Methods: Primary caregivers of males with DBMD in the Muscular Dystrophy Surveillance and Research Tracking Network (MD STARnet) were surveyed during 2011–2012 on family quality of life measures, including labor market outcomes. Of 211 respondents, 96 female caregivers of boys with DBMD were matched on state, year of survey, respondent's age, child's age, and number of minor children with controls constructed from Current Population Survey extracts. Regression analysis was used to estimate labor market outcomes and productivity costs. Results: Caregivers of boys with DBMD worked 296 h less per year on average than caregivers of unaffected children, translating to a $8816 earnings loss in 2020 U.S. dollars. Caregivers of boys with DMD with ≥4 y of ambulation loss had a predicted loss in annualized earnings of $23,995, whereas caregivers of boys with DBMD of the same ages who remained ambulatory had no loss of earnings. Discussion Female caregivers of non‐ambulatory boys with DMD face additional household budget constraints through income loss. Failure to include informal care costs in economic studies could understate the societal cost‐effectiveness of strategies for managing DMD that might prolong ambulation. [ABSTRACT FROM AUTHOR]

Introduction/Aims: As life expectancy improves for patients with Duchenne muscular dystrophy (DMD), new symptoms are likely to arise. This aims of this study are: (1) to explore the prevalence of a broad variety of symptoms in the various stages of DMD (with and without steroid use); (2) to explore the prevalence of common secondary diagnoses; and (3) to evaluate the social participation level of patients with DMD older than 16 y of age; and to explore correlations between social participation and symptoms. Methods: A cross‐sectional self‐report questionnaire, including questions on functional level and health status, as well as a standardized participation scale was distributed among Dutch patients with DMD. Results: Eighty‐four male patients with a mean age of 22.0 (SD = 10.0) y were enrolled. The most prevalent and limiting symptoms were difficulty coughing (58%), coldness of hands (57%), contractures (51%), stiffness (49%), fatigue (40%), myalgia (38%), and low speech volume (33%). Prevalent secondary diagnoses included cardiac disease (14%), neurobehavioral diagnosis (13%), low blood pressure (13%), and arthrosis (5%). Social participation correlated negatively with coldness of hands (r = −.29; P <.03), decreased intelligibility (r = −.40; P <.003), and chewing problems (r = −.33; P <.02). Discussion: The prevalence of a broad spectrum of symptoms and secondary diagnoses is high in patients with DMD, and some of these symptoms are correlated with social participation. Growing awareness of new symptoms and secondary diagnoses among patients, caregivers, and professionals can enhance their recognition, possibly facilitating prevention and early treatment. [ABSTRACT FROM AUTHOR]

Introduction/Aims: Amyotrophic lateral sclerosis (ALS) symptoms mimic those of other conditions and often require multiple physician and healthcare contacts for investigation and accurate diagnosis. We examined the type and frequency of healthcare service utilization prior to ALS diagnosis and tracheostomy‐free survival by sex and rurality among individuals treated with riluzole in Ontario, Canada. Methods: This population‐based cohort study used administrative databases to identify patients aged 18+ y diagnosed with ALS and started on riluzole between April 2002–March 2018. Using Poisson regression, rate ratios of healthcare utilization and atypical diagnostic tests and unnecessary therapeutic interventions 5 y prior to ALS diagnosis were compared by sex and rurality. Tracheostomy‐free survival after diagnosis was compared between groups using Kaplan–Meier estimators and proportional hazards models. Results: A total of 1071 patients with ALS were identified with a mean age of 70 y; 563 (52.6%) were men and 134 (12.5%) were rural residents. The number of physician visits increased in the 18 mo prior to ALS diagnosis. We observed modest sex differences in healthcare utilization. Rural patients had lower neurologist visit rates (rate ratio [RR], 0.78; 95% confidence interval [CI], 0.70–0.87) and were significantly more likely to receive an atypical diagnostic test or unnecessary therapeutic intervention (RR, 1.80; 95% CI, 1.04–3.10). Tracheostomy‐free survival did not differ by sex (log‐rank P‐value =.78) or rurality (log‐rank P‐value =.84). Discussion Given disparities observed in healthcare of rural ALS patients, policy strategies are needed to ensure all patients have timely access to care along the pathway from symptom onset to ALS diagnosis, to enable access to new therapeutics and clinical trials. [ABSTRACT FROM AUTHOR]

See article on pages 397‐403 in this issue [ABSTRACT FROM AUTHOR]

Introduction/Aims: Spinal muscular atrophy type 1 (SMA 1) is a devastating motor neuron disorder that leads to progressive muscle weakness, respiratory failure and premature death. Although sensory electrophysiological changes have been anecdotally found in pediatric SMA 1 patients, the age of onset of sensory neuropathy remains unknown. Methods: Sensory nerve conduction studies of the median and sural nerves were performed in 28 consecutive SMA 1 patients of different ages. Sensory nerve conduction velocities and sensory nerve action potential (SNAP) amplitudes recorded in these patients were compared with those obtained from 93 healthy subjects stratified by age. Results: SNAP amplitudes decreased with increasing age in the sural and median nerves, without any significant difference between upper and lower limbs. Discussion: Our data suggest that sural and median nerve SNAP amplitudes are normal in younger patients, while an axonal neuropathy appears in older ones. [ABSTRACT FROM AUTHOR]