Predictors of diagnostic delay in amyotrophic lateral sclerosis: a cohort study based on administrative and electronic medical records data

Time to diagnosis and determinants of diagnostic delays of people living with a rare disease: results of a Rare Barometer retrospective patient survey

Timely diagnosis is one of the most serious challenges faced by people living with a rare disease (PLWRD), and this study estimates that in Europe, the average total diagnosis time (TDT) is close to 5 years. We investigated the duration of the TDT for PLWRD in Europe, the difficulties associated with their diagnosis odyssey and the main determinants of diagnosis delays for all rare diseases (RD). We conducted a survey of PLWRD and their families using Rare Barometer, the survey initiative of EURORDIS-Rare Diseases Europe. In geographical Europe, we surveyed 6507 people living with 1675 RD in 41 countries. We then performed a descriptive analysis and ordinal logistic regressions to identify the main determinants of diagnosis delays. Average TDT is 4.7 years. 56% of respondents were diagnosed more than 6 months after a first medical contact. The main determinants of diagnosis delays are symptom onset before 30 years of age, especially during childhood (OR = 3.11; 95% CI: 2.4-4.0) and adolescence (OR = 4.79; 95% CI: 3.7-6.2), being a woman (OR = 1.22; 95% CI:1.1-1.4), living in Northern Europe (OR = 2.15; 95% CI:1.8-2.6) or Western Europe (OR = 1.96; 95% CI:1.6-2.3), the number of healthcare professionals consulted (OR = 5.15; 95% CI:4.1-6.4), misdiagnosis (OR = 2.48; 95% CI:2.1-2.9), referral to a centre of expertise (OR = 1.17; 95% CI:1.0-1.3), unmet needs for psychological support (OR = 1.34; 95% CI:1.2-1.5) and financial support (OR = 1.16; 95% CI:1.0-1.3), having a genetic disease (OR = 1.33; 95% CI:1.1-1.5) and a family history of an RD (OR = 1.36; 95% CI:1.1-1.6). These determinants can inform policies and actions to improve access to diagnosis for all PLWRD.

Whole-body fasciculation detection in amyotrophic lateral sclerosis using motor unit MRI

OBJECTIVE

Compare fasciculation rates between amyotrophic lateral sclerosis (ALS) patients and healthy controls in body regions relevant for diagnosing ALS using motor unit MRI (MUMRI) at baseline and 6 months follow-up, and relate this to single-channel surface EMG (SEMG).

METHODS

Tongue, biceps brachii, paraspinals and lower legs were assessed with MUMRI and biceps brachii and soleus with SEMG in 10 healthy controls and 10 patients (9 typical ALS, 1 primary lateral sclerosis [PLS]).

RESULTS

MUMRI-detected fasciculation rates in typical ALS patients were higher compared to healthy controls for biceps brachii (2.40 ± 1.90 cm-3min-1vs. 0.04 ± 0.10 cm-3min-1, p = 0.004), paraspinals (1.14 ± 1.61 cm-3min-1vs. 0.02 ± 0.02 cm-3min-1, p = 0.016) and lower legs (1.42 ± 1.27 cm-3min-1vs. 0.13 ± 0.10 cm-3min-1, p = 0.004), but not tongue (1.41 ± 1.94 cm-3min-1vs. 0.18 ± 0.18 cm-3min-1, p = 0.556). The PLS patient showed no fasciculation. At baseline, 6/9 ALS patients had increased fasciculation rates compared to healthy controls in at least 2 body regions. At follow-up every patient had increased fasciculation rates in at least 2 body regions. The MUMRI-detected fasciculation rate correlated with SEMG-detected fasciculation rates (τ = 0.475, p = 0.006).

CONCLUSION

MUMRI can non-invasively image fasciculation in multiple body regions and appears sensitive to disease progression in individual patients.

SIGNIFICANCE

MUMRI has potential as diagnostic tool for ALS.

Diagnostic delay in amyotrophic lateral sclerosis

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a progressive, fatal neurodegenerative disease, and the time from symptom onset to diagnosis remains long. With the advent of disease-modifying treatments, the need to identify and diagnose ALS in a timely fashion has never been greater.

METHODS

We reviewed the literature to define the severity of ALS diagnostic delay, the various factors that contribute to this delay (including patient and physician factors), and the role that site of symptom onset plays in a patient's diagnostic journey.

RESULTS

Diagnostic delay is influenced by general practitioners' lack of recognition of ALS due to disease rarity and heterogenous presentations. As a result, patients are referred to non-neurologists, have unnecessary diagnostic testing, and may ultimately be misdiagnosed. Patient factors include their illness behavior-which impacts diagnostic delay-and their site of symptom onset. Limb-onset patients have the greatest diagnostic delay because they are frequently misdiagnosed with degenerative spine disease or peripheral neuropathy.

CONCLUSION

Prompt ALS diagnosis results in more effective clinical management, with earlier access to disease-modifying therapies, multidisciplinary care, and, if desired, clinical trial involvement. Due to lack of commercially available ALS biomarkers, alternative strategies to identify and triage patients who likely have ALS must be employed. Several diagnostic tools have been developed to encourage general practitioners to consider ALS and make an urgent referral to ALS specialists, bypassing unnecessary referrals to non-neurologists and unnecessary diagnostic workup.

Limited value of serum neurofilament light chain in diagnosing amyotrophic lateral sclerosis

A biomarker specific for the diagnosis of amyotrophic lateral sclerosis must be sensitive across a spectrum of clinical heterogeneity. Neurofilament light chain levels in amyotrophic lateral sclerosis correlate with the rate of disability progression. Previous attempts to establish a diagnostic role for neurofilament light chain have been limited to comparison with healthy individuals or controls with alternative diagnoses unlikely to be confused with amyotrophic lateral sclerosis in real-world clinical practice. In a tertiary amyotrophic lateral sclerosis referral clinic, at first visit, serum was taken for neurofilament light chain measurement after prospectively recording the clinical diagnosis as 'amyotrophic lateral sclerosis', 'primary lateral sclerosis', 'alternative' or 'currently uncertain'. Of 133 referrals, 93 patients were diagnosed with amyotrophic lateral sclerosis (median neurofilament light chain 218.1 pg/ml, interquartile range 130.7-311.9), three primary lateral sclerosis (65.6, 51.5-106.9) and 19 alternative diagnoses (45.2, 13.5-71.9) at first visit. Of 18 initially uncertain diagnoses, eight were subsequently diagnosed with amyotrophic lateral sclerosis (98.5, 45.3-300.1). Neurofilament light chain ≥110.9 pg/ml had a positive predictive value of 0.92 for amyotrophic lateral sclerosis; <110.9 pg/ml had a negative predictive value of 0.48. In a specialized clinic, neurofilament light chain is largely confirmatory to clinical judgement in diagnosing amyotrophic lateral sclerosis and has limited ability to exclude alternative diagnoses. The current, important, value of neurofilament light chain is its potential to stratify patients with amyotrophic lateral sclerosis by disease activity and as a biomarker in therapeutic trials.

Implications of Artificial Intelligence Algorithms in the Diagnosis and Treatment of Motor Neuron Diseases-A Review

Motor neuron diseases (MNDs) are a group of chronic neurological disorders characterized by the progressive failure of the motor system. Currently, these disorders do not have a definitive treatment; therefore, it is of huge importance to propose new and more advanced diagnoses and treatment options for MNDs. Nowadays, artificial intelligence is being applied to solve several real-life problems in different areas, including healthcare. It has shown great potential to accelerate the understanding and management of many health disorders, including neurological ones. Therefore, the main objective of this work is to offer a review of the most important research that has been done on the application of artificial intelligence models for analyzing motor disorders. This review includes a general description of the most commonly used AI algorithms and their usage in MND diagnosis, prognosis, and treatment. Finally, we highlight the main issues that must be overcome to take full advantage of what AI can offer us when dealing with MNDs.

Self-reported factors contributing to delay in ALS diagnosis among primary care providers in a large Ohio-based US healthcare network

OBJECTIVE

This study's primary objective is to identify self-reported factors that contribute to diagnostic delay in ALS among Primary Care Providers (PCPs).

METHODS

A de novo email-based survey was deployed to Ohio-based PCPs in the Cleveland Clinic Health System.

RESULTS

Of the 77 PCP participants [including 30 Advance Practice Providers (APPs)] only: (a) 18% of physicians, and 3% of APPs were very confident or confident with recognizing signs and symptoms of ALS, (b) 13% of physicians, and 21% of APP s felt very confident or confident with distinguishing between a neurologic cause of dysfunction from other possible causes, and (c) 23% of physicians, and 11% of APPs felt very confident or confident with distinguishing between upper and lower motor neuron signs. If presented with a weak patient without a specific diagnosis, PCPs most frequently ordered electrodiagnostic testing, brain MRI, cervical or thoracic spine MRI, and serum creatine kinase. PCPs identified top reasons for delayed ALS diagnosis as: (a) patient's delay in seeking medical help, (b) diagnostic uncertainty (c) waiting time for neurology/neuromuscular medicine (NM) consultation. The most desired strategies to shorten diagnostic delay involved: (a) educating PCPs and other non-neurologist "gatekeeper" providers, (b) improving access to specialist neurology care, and (c) developing a reliable diagnostic test for ALS.

DISCUSSION

Self-reported factors that increase ALS diagnostic delay among PCPs primarily comprise gaps in clinical knowledge and skills required to detect key symptoms and signs, and suboptimal referral access to a neurology/NM provider. These areas represent important opportunities for targeted improvement efforts.

The path to diagnosis in ALS: delay, referrals, alternate diagnoses, and clinical progression

Objective: To provide a detailed and differentiated description of the path to receiving the correct amyotrophic lateral sclerosis (ALS) diagnosis, including delay times, referrals, alternate diagnoses, and clinical progression.Methods: Medical records until the date of ALS diagnosis were reviewed and linked to the Swedish Motor Neuron Disease Quality Registry.Results: The study included 353 Stockholm ALS patients diagnosed in 2016-2021. Patients were divided into four groups: 117 (33.1%) with lower extremity (LE), 85 (24.1%) with upper extremity (UE), 136 (38.5%) with bulbar, and 15 (4.2%) with respiratory onset. The time from onset to diagnosis was 16.0 (9.4-27.5) months in LE, 12.9 (8.8-17.8) months in UE, 11.7 (7.4-16.0) months in bulbar, and 8.3 (4.7-15.6) months in respiratory onset. Patients with UE or LE onset were often referred to orthopedics or a spinal/hand surgery clinic (29.3% for LE and 41.8% for UE), while bulbar patients were more frequently referred to ENT (66.3%). For those with LE or UE onset, the most common alternate diagnosis was spinal/foraminal stenosis whereas myasthenia gravis and stroke were more common for bulbar onset patients. For the respiratory group, cardiopulmonary diagnoses predominated. The proportion of all patients in King's stage 3 or 4 increased from 11.3% to 46.1% from the initial health care visit to diagnosis.Conclusions: There was great variation in the path to ALS diagnosis according to the onset clinical phenotype. In all groups, the diagnostic delay and clinical progression was substantial. We identified subgroups where the delay was the longest and might be reduced.

Advances in sequencing technologies for amyotrophic lateral sclerosis research

Amyotrophic lateral sclerosis (ALS) is caused by upper and lower motor neuron loss and has a fairly rapid disease progression, leading to fatality in an average of 2-5 years after symptom onset. Numerous genes have been implicated in this disease; however, many cases remain unexplained. Several technologies are being used to identify regions of interest and investigate candidate genes. Initial approaches to detect ALS genes include, among others, linkage analysis, Sanger sequencing, and genome-wide association studies. More recently, next-generation sequencing methods, such as whole-exome and whole-genome sequencing, have been introduced. While those methods have been particularly useful in discovering new ALS-linked genes, methodological advances are becoming increasingly important, especially given the complex genetics of ALS. Novel sequencing technologies, like long-read sequencing, are beginning to be used to uncover the contribution of repeat expansions and other types of structural variation, which may help explain missing heritability in ALS. In this review, we discuss how popular and/or upcoming methods are being used to discover ALS genes, highlighting emerging long-read sequencing platforms and their role in aiding our understanding of this challenging disease.

Diagnostic delay in rare diseases: data from the Spanish rare diseases patient registry

BACKGROUND

According to the International Rare Diseases Research Consortium (IRDiRC), a known rare disease (RD) should be diagnosable within a year. This study sought: firstly, to ascertain how long it takes to obtain the diagnosis of a RD in Spain, along with its associated time trend; and secondly, to identify and measure diagnostic delay (defined by the IRDiRC as any period exceeding a year) by reference to the characteristics of RDs and the persons affected by them.

METHODS

Using data sourced from the Spanish Rare Diseases Patient Registry, we performed a descriptive analysis of the time elapsed between symptom onset and diagnosis of each RD, by sex, age and date of symptom onset, and type of RD. We analysed the time trend across the period 1960-2021 and possible change points, using a Joinpoint regression model and assuming a Poisson distribution. The multivariate analysis was completed with backward stepwise logistic regression.

RESULTS

Detailed information was obtained on 3304 persons with RDs: 56.4% had experienced delay in diagnosis of their RDs, with the mean time taken being 6.18 years (median = 2; IQR 0.2-7.5). Both the percentage of patients with diagnostic delay and the average time to diagnosis underwent a significant reduction across the study period (p < 0.001). There was a higher percentage of diagnostic delays: in women (OR 1.25; 95% CI 1.07-1.45); in cases with symptom onset at age 30-44 years (OR 1.48; 95% CI 1.19-1.84): and when analysed by type of RD, in mental and behavioural disorders (OR 4.21; 95% CI 2.26-7.85), followed by RDs of the nervous system (OR 1.39; 95% CI 1.02-1.88).

CONCLUSIONS

This is the first study to quantify time to diagnosis of RDs in Spain, based on data from a national registry open to any RD. Since over half of all persons affected by RDs experience delay in diagnosis, new studies are needed to ascertain the factors associated with this delay and the implications this has on the lives of patients and their families.

Effect of neurofilament analysis on the diagnostic delay in amyotrophic lateral sclerosis

AIMS

The aim of this study was to investigate whether neurofilament light (NfL) and phosphorylated neurofilament heavy (pNfH) in cerebrospinal fluid (CSF), sampled prior to referral to a neuromuscular reference center (NMRC), shorten the diagnostic delay in patients with amyotrophic lateral sclerosis.

METHODS

In this retrospective study, patients with ALS were included with (i) determination of neurofilaments (Nfs) before referral to the NMRC (preC-Nfs ALS, n = 58), (ii) determination of Nfs at the NMRC (C-Nfs, n = 54) or (iii) with no determination of Nfs (C-No Nfs, n = 180). Fifty-six disease controls were included.

RESULTS

The preC-Nfs cohort had CSF sampled 2.2 months (range: 0.6-12.0 months) before referral to the NMRC. In this cohort, the diagnostic delay was significantly shorter [median (range): 8.24 (2.37-49.7) months] than in the C-Nfs cases [median (range): 11.4 (2.93-86.5) months; p < 0.05], but not in the C-No Nfs cases. When including the disease progression rate and the presence of a genetic mutation as covariates, the difference ceased to exist (p = 0.14). pNfH and NfL levels in the preC-Nfs cohort were significantly higher than in disease controls (p < 0.0001). Both Nfs showed a similar discriminating performance.

CONCLUSIONS

CSF Nfs assessed before the diagnosis of ALS at a NMRC decreased the diagnostic delay in specific cases by 3 months and only when other covariates were not taken into account.

Hastening the Diagnosis of Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a chronic progressive neurodegenerative disease. Neurologists generally see patients as requested and as schedules allow. This practice is part of the reason it takes approximately 12 months from onset of new progressive weakness to receive a definitive diagnosis of ALS. It is well recognized that the disease of ALS starts long before symptom onset. In mutant SOD1 transgenic mice, early loss of motor neurons and compensatory morphological changes precede a rapid loss of motor neurons that coincides with symptom onset. In a human autopsy study, anterior roots in the "presymptomatic" stage indicate that ∼20% loss of motor neurons had already occurred. Sera collected from individuals who later developed ALS and sera from presymptomatic members of families with ALS harboring pathogenic gene variants demonstrated high neurofilament (Nf) levels, again suggesting that the neurodegenerative process is already active at a clinically presymptomatic stage. Potential benefits of hastening the diagnosis of ALS include earlier initiation of therapy to slow the fundamental neurodegenerative process. Such effects are observed in treatment with riluzole, edaravone, methylcobalamin, and sodium phenylbutyrate-taurursodiol in patient care and clinical trial settings. Early initiation of multidisciplinary care results in cost savings and prolonged survival. Early diagnosis after symptom onset also seems to reduce psychological distress. Hence, how can we facilitate an earlier diagnosis of ALS? We already have the necessary tools. New and simple ALS diagnostic criteria (Gold Coast Criteria) have been introduced along with genetic testing. At least 2 studies provide Class II evidence that establishes the reliability and sensitivity of CSF and/or serum Nf levels in supporting a diagnosis of ALS. Challenges, however, still exist as to how to facilitate earlier recognition of possible ALS by primary care physicians and other nonneurologist providers and how to foster a sense of urgency among neurologists to accelerate the diagnostic process. In this article, we provide a number of recommendations that we hope will help achieve these ends.

Misdiagnoses in a Brazilian population with amyotrophic lateral sclerosis

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that affects the upper and lower motor neurons. The correct diagnosis at the onset of the disease is sometimes very difficult, due to the symptoms being very similar to those of other neurological syndromes.

OBJECTIVE

This study aimed to analyze the initial manifestations, the specialty of the first physician visited due the initial complaint, the misdiagnoses, as well as the unnecessary surgical interventions in a new ALS Brazilian population.

METHODS

The medical records of 173 patients with typical ALS were reviewed.

RESULTS

The present study demonstrated that other symptoms, besides weakness, were very frequent as initial presentation of ALS, and orthopedics was the medical specialty most sought by patients at the onset of symptoms. Our frequency of misdiagnoses was 69.7%, and in 7.1% of them, an unnecessary surgical intervention was performed.

CONCLUSIONS

Amyotrophic lateral sclerosis presents a very large pool of signs and symptoms; therefore, there is an urgent need of increasing the disease awareness to other specialties due to the high frequency of misdiagnoses observed in clinical practice.

Pain in amyotrophic lateral sclerosis: a narrative review

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative condition characterized by loss of motor neurons, resulting in motor weakness of the limbs and/or bulbar muscles. Pain is a prevalent but neglected symptom of ALS, and it has a significant negative impact on the quality of life of patients and their caregivers. This review outlines the epidemiology, clinical characteristics, underlying mechanisms, and management strategies of pain in ALS to improve clinical practice and patient outcomes related to pain. Pain is a prevalent symptom among patients with ALS, with a variable reported prevalence. It may occur at any stage of the disease and can involve any part of the body without a specific pattern. Primary pain includes neuropathic pain and pain from spasticity or cramps, while secondary pain is mainly nociceptive, occurring with the progression of muscle weakness and atrophy, prolonged immobility causing degenerative changes in joints and connective tissue, and long-term home mechanical ventilation. Prior to treatment, the exact patterns and causes of pain must first be identified, and the treatment should be tailored to each patient. Treatment options can be classified into pharmacological treatments, including nonsteroidal anti-inflammatory drugs, antiepileptic drugs, drugs for cramps or spasticity, and opioid; and nonpharmacological treatments, including positioning, splints, joint injections, and physical therapy. The development of standardized and specific assessment tools for pain-specific to ALS is required, as are further studies on treatments to reduce pain, diminish suffering, and improve the quality of life of patients with ALS.

Diagnostic Process in Rare Diseases: Determinants Associated with Diagnostic Delay

Many people living with rare disease (RD) report a difficult diagnostic process from the symptom onset until they obtain the definitive diagnosis. The aim of this study was thus to ascertain the diagnostic process in RDs, and explore the determinants related with having to wait for more than one year in this process (defined as “diagnostic delay”). We conducted a case–control study, using a purpose-designed form from the Spanish Rare Diseases Patient Registry for data-collection purposes. A descriptive analysis was performed and multivariate backward logistic regression models fitted. Based on data on 1216 patients living with RDs, we identified a series of determinants associated with experiencing diagnostic delay. These included: having to travel to see a specialist other than that usually consulted in the patient’s home province (OR 2.1; 95%CI 1.6–2.9); visiting more than 10 specialists (OR 2.6; 95%CI 1.7–4.0); being diagnosed in a region other than that of the patient’s residence at the date of symptom onset (OR 2.3; 95%CI 1.5–3.6); suffering from a RD of the nervous system (OR 1.4; 95%CI 1.0–1.8). In terms of time taken to see a specialist, waiting more than 6 months to be referred from the first medical visit was the period of time which most contributed to diagnostic delay (PAR 30.2%). In conclusion, this is the first paper to use a collaborative study based on a nationwide registry to address the diagnostic process of patients living with RDs. While the evidence shows that the diagnostic process experienced by these persons is complex, more studies are needed to determine the implications that this has for their lives and those of their families at a social, educational, occupational, psychological, and financial level.

Early and progressive dysfunction revealed by in vivo neurite imaging in the rNLS8 TDP-43 mouse model of ALS

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Are neurite density and dispersion altered in amyotropic lateral sclerosis (ALS)?

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Both measures are affected in the rNLS8 TDP-43 mouse model of ALS.

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Diffusion tensor imaging metrics were also affected.

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Group-wise changes were observed early in the disease course.

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Together these diffusion imaging metrics may aid in the timelier diagnosis of ALS.

Amyotrophic lateral sclerosis (ALS) is characterized by transactive response DNA-binding protein 43 (TDP-43) pathology, progressive loss of motor neurons and muscle dysfunction. Symptom onset can be insidious and diagnosis challenging. Conventional neuroimaging is used to exclude ALS mimics, however more advanced neuroimaging techniques may facilitate an earlier diagnosis. Here, we investigate the potential for neurite orientation dispersion and density imaging and diffusion tensor imaging (DTI) to detect microstructural changes in an experimental model of ALS with neuronal doxycycline (Dox)-suppressible overexpression of human TDP-43 (hTDP-43). In vivo diffusion-weighted imaging (DWI) was acquired 1- and 3- weeks following the initiation of hTDP-43 expression (post-Dox) to investigate whether neurite density imaging (NDI) and orientation dispersion imaging (ODI) are affected early in this preclinical model of ALS and if so, how these metrics compare to those derived from the diffusion tensor. Tract-based spatial statistics at 1-week post-Dox, i.e. very early in the disease stage, demonstrated increased NDI in TDP-43 mice but no change in ODI or DTI metrics. At 3-weeks post-Dox, a reduced pattern of increased NDI was observed along with widespread increases in ODI, and decreased fractional anisotropy (FA), apparent diffusion coefficient (ADC) and axial diffusivity (AD). A hypothesis driven analysis of the bilateral corticospinal tracts demonstrated that at 1-week post-Dox, ODI was significantly increased caudally but decreased in the motor cortex of TDP-43 mice. Decreased cortical ODI had normalized by 3-weeks post-Dox and only significant increases were observed. A similar, but inverse pattern in FA was also observed. Together, these results suggest a non-monotonic relationship between DWI metrics and pathophysiological progression with TDP-43 mice exhibiting significantly altered diffusion metrics consistent with early inflammation followed by progressive axonal degeneration. Importantly, significant group-wise changes were observed in the earliest stages of disease when subtle pathology may be more elusive to traditional structural imaging techniques.

The Cure VCP Scientific Conference 2021: Molecular and clinical insights into neurodegeneration and myopathy linked to multisystem proteinopathy-1 (MSP-1)

The 2021 VCP Scientific Conference took place virtually from September 9–10, 2021. This conference, planned and organized by the nonprofit patient advocacy group Cure VCP Disease, Inc. (https://www.curevcp.org), was the first VCP focused meeting since the 215th ENMC International Workshop VCP-related multi-system proteinopathy in 2016 (Evangelista et al., 2016). Mutations in VCP cause a complex and heterogenous disease termed inclusion body myopathy (IBM) with Paget’s disease of the bone (PDB) and frontotemporal dementia (FTD) (IBMPFD), or multisystem proteinopathy 1 (MSP-1) Kimonis (n.d.), Kovach et al. (2001), Kimonis et al. (2000). In addition, VCP mutations also cause other age-related neurodegenerative disorders including amyptrophic lateral sclerosis (ALS), Parkinsonism, Charcot-Marie type II-B, vacuolar tauopathy among others (Korb et al., 2022). The objectives of this conference were as follows: (1) to provide a forum that facilitates sharing of published and unpublished information on physiological roles of p97/VCP, and on how mutations of VCP lead to diseases; (2) to bolster understanding of mechanisms involved in p97/VCP-relevant diseases and to enable identification of therapeutics to treat these conditions; (3) to identify gaps and barriers of further discoveries and translational research in the p97/VCP field; (4) to set a concrete basic and translational research agenda for future studies including crucial discussions on biomarker discoveries and patient longitudinal studies to facilitate near-term clinical trials; (5) to accelerate cross-disciplinary research collaborations among p97/VCP researchers; (6) to enable attendees to learn about new tools and reagents with the potential to facilitate p97/VCP research; (7) to assist trainees in propelling their research and to foster mentorship from leaders in the field; and (8) to promote diversity and inclusion of under-represented minorities in p97/VCP research as diversity is critically important for strong scientific research. Given the range of topics, the VCP Scientific Conference brought together over one hundred and forty individuals representing a diverse group of research scientists, trainees, medical practitioners, industry representatives, and patient advocates. Twenty-five institutions with individuals from thirteen countries attended this virtual meeting. In this report, we summarize the major topics presented at this conference by a range of experts.

Natural history and remarkable psychiatric state of late-onset amyotrophic lateral sclerosis in China

OBJECTIVE

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease affecting motor neurons. The proportion of late-onset ALS in China were low and may have distinct clinical and genetic manifestations. We aimed to investigate the natural history and remarkable psychiatric state of ALS with age at onset over 60 years in China.

MATERIALS AND METHODS

We collected all ALS cases from 2017 to 2020 in our center and focused on late-onset ALS patients particularly, by analyzing the clinical data, including the ALS onset and disease progression. Anxiety, depression, cognitive function, and sleep quality were assessed to reflect the psychiatric state.

RESULTS

A total of 193 late-onset ALS patients were included in this study. The median age at onset of late-onset ALS was 65 years with the quartile from 62 to 68 years. When compared with 446 non-late-onset ALS, late-onset ALS showed distinct clinical presentation, with lower ALS Functional Rating Scale-Revised at diagnosis and faster rate of progression. Remarkably, late-onset ALS were suffering from worse psychiatric state, including serious anxiety and depression, as well as worse cognitive function with sleep quality. The abnormal psychiatric state was more pronounced in female patients of late-onset.

CONCLUSIONS

In the current study, ALS patients with late-onset showed unique clinical features. Severe psychiatric conditions and faster progression in the early stage of the disease of late-onset ALS indicated the need for more social and psychiatric support in this population.

TDP-43 Cytoplasmic Translocation in the Skin Fibroblasts of ALS Patients

Diagnosis of ALS is based on clinical symptoms when motoneuron degeneration is significant. Therefore, new approaches for early diagnosis are needed. We aimed to assess if alterations in appearance and cellular localization of cutaneous TDP-43 may represent a biomarker for ALS. Skin biopsies from 64 subjects were analyzed: 44 ALS patients, 10 healthy controls (HC) and 10 neurological controls (NC) (Parkinson’s disease and multiple sclerosis). TDP-43 immunoreactivity in epidermis and dermis was analyzed, as well as the percentage of cells with TDP-43 cytoplasmic localization. We detected a higher amount of TDP-43 in epidermis (p < 0.001) and in both layers of dermis (p < 0.001), as well as a higher percentage of TDP-43 cytoplasmic positive cells (p < 0.001) in the ALS group compared to HC and NC groups. Dermal cells containing TDP-43 were fibroblasts as identified by co-labeling against vimentin. ROC analyses (AUC 0.867, p < 0.001; CI 95% 0.800–0.935) showed that detection of 24.1% cells with cytoplasmic TDP-43 positivity in the dermis had 85% sensitivity and 80% specificity for detecting ALS. We have identified significantly increased TDP-43 levels in epidermis and in the cytoplasm of dermal cells of ALS patients. Our findings provide support for the use of TDP-43 in skin biopsies as a potential biomarker.

Delayed Diagnosis and Diagnostic Pathway of ALS Patients in Portugal: Where Can We Improve?

Background: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease with unsatisfactory treatment options. Best management and recruitment into clinical trials requires early diagnosis. However, diagnosis is often delayed. Analysis of the diagnostic pathway and identification of the causes of diagnostic delay are imperative. Methods: We studied a cohort of 580 ALS patients followed up in our ALS clinic in Lisbon. Demographic, disease, and sociocultural factors were collected. Time from first symptom onset to diagnosis, the specialist's assessment, and investigations requested were analyzed. Predictors of diagnostic delay were evaluated by multivariate linear regression, adjusting for potential confounders. Results: The median diagnostic delay from first symptom onset was 10 months. Spinal-onset, slower disease progression, cognitive symptoms at onset, and lower income were associated with increased diagnostic delay. Most patients were first assessed by general practitioners. Patients who were first evaluated by a neurologist were more likely to be correctly diagnosed, decreasing time to diagnosis. Electromyography was decisive in establishing the diagnosis. Conclusions: Late referral from non-neurologists to a neurologist is a potentially modifiable factor contributing to significant diagnostic delay. Educational interventions targeted to non-neurologists physicians, in order to increase awareness of ALS and, consequently, promote early referral to a neurologist at a tertiary center, will be important in reducing diagnostic delay.

Neuroprotective Effects of Shenqi Fuzheng Injection in a Transgenic SOD1-G93A Mouse Model of Amyotrophic Lateral Sclerosis

Background: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease, in the pathogenesis of which oxidative stress (OS) was believed to play a key role. Shenqi Fuzheng Injection (SFI) concocted from two kinds of Chinese medicinal herbs, Radix Codonopsis and Radix Astragali, was proven to be eligible to reduce the OS injury and increase the activity of the nuclear factor-erythroid-2–related factor 2 (Nrf2) pathway, an antioxidant enzymes inducer.

Objective: We aim to investigate the effects and potential mechanisms underlying the action of SFI on a well-established transgenic mouse model of ALS.

Methods: Transgenic SOD1-G93A mice were intraperitoneally injected with SFI (40 ml/kg) three times a week from 87 days of age. Motor function, survival, pathological manifestations in the brain, and Nrf2 pathway-related assessments of the mice were performed.

Results: SFI treatment efficiently postponed the disease onset (p = 0.022) and extended the overall survival (p = 0.038) of the SOD1-G93A mice. Moreover, SFI significantly reduced motor neuron loss (p < 0.001) and astrocytic activation (p < 0.05) in the motor cortex of the brain of SOD1-G93A mice at 130 days of age. The protective effects of SFI in the SOD1-G93A mice were associated with decreasing the level of malondialdehyde (p < 0.05) and increasing the levels of superoxide dismutase (p < 0.05), Nrf2 (p < 0.05), heme oxygenase-1 (p < 0.05), and glutathione S-transferase (p < 0.05) in the SOD1-G93A mice.

Conclusion: The SFI treatment efficiently extended the overall survival and improved the pathological manifestations of the brain via alleviating the OS injury and activating the Nrf2 pathway in the animal model of ALS, which made SFI a potentially promising candidate for ALS treatment.

1H Magnetic Resonance Spectroscopy to Understand the Biological Basis of ALS, Diagnose Patients Earlier, and Monitor Disease Progression

At present, limited biomarkers exist to reliably understand, diagnose, and monitor the progression of amyotrophic lateral sclerosis (ALS), a fatal neurological disease characterized by motor neuron death. Standard MRI technology can only be used to exclude a diagnosis of ALS, but ¹H-MRS technology, which measures neurochemical composition, may provide the unique ability to reveal biomarkers that are specific to ALS and sensitive enough to diagnose patients at early stages in disease progression. In this review, we present a summary of current theories of how mitochondrial energetics and an altered glutamate/GABA neurotransmitter flux balance play a role in the pathogenesis of ALS. The theories are synthesized into a model that predicts how pathogenesis impacts glutamate and GABA concentrations. When compared with the results of all MRS studies published to date that measure the absolute concentrations of these neurochemicals in ALS patients, results were variable. However, when normalized for neuronal volume using the MRS biomarker N-acetyl aspartate (NAA), there is clear evidence for an elevation of neuronal glutamate in nine out of thirteen studies reviewed, an observation consistent with the predictions of the model of increased activity of glutamatergic neurons and excitotoxicity. We propose that this increase in neuronal glutamate concentration, in combination with decreased neuronal volume, is specific to the pathology of ALS. In addition, when normalized to glutamate levels, there is clear evidence for a decrease in neuronal GABA in three out of four possible studies reviewed, a finding consistent with a loss of inhibitory regulation contributing to excessive neuronal excitability. The combination of a decreased GABA/Glx ratio with an elevated Glx/NAA ratio may enhance the specificity for ¹H-MRS detection of ALS and ability to monitor glutamatergic and GABAergic targeted therapeutics. Additional longitudinal studies calculating the exact value of these ratios are needed to test these hypotheses and understand how ratios may change over the course of disease progression. Proposed modifications to the experimental design of the reviewed ¹H MRS studies may also increase the sensitivity of the technology to changes in these neurochemicals, particularly in early stages of disease progression.

Health services utilization prior to amyotrophic lateral sclerosis diagnosis: A province-wide study of individuals treated with riluzole in Ontario, Canada

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.

Estimated Prevalence and Incidence of Amyotrophic Lateral Sclerosis and SOD1 and C9orf72 Genetic Variants

INTRODUCTION

Amyotrophic lateral sclerosis (ALS) is a rare neurological disorder characterized by progressive deterioration of motor neurons. Assessment of the size/geographic distribution of the ALS population, including ALS with genetic origin, is needed to understand the burden of the disease and the need for clinical intervention and therapy.

OBJECTIVES

The main objective of this study was to estimate the number of prevalent and incident ALS cases overall and superoxide dismutase 1 (SOD1) and chromosome 9 open reading frame 72 (C9orf72) ALS in 22 countries across Europe (Belgium, France, Germany, Ireland, Italy, Netherlands, Norway, Russia, Spain, Sweden, and UK), North America (USA and Canada), Latin America (Argentina, Brazil, Colombia, Mexico, and Uruguay), and Asia (China, Japan, South Korea, and Taiwan).

METHODS

A comprehensive literature search was conducted to identify population-based studies reporting ALS prevalence and/or incidence rates. Pooled prevalence and incidence rates were obtained using a meta-analysis approach at the country and regional geographic level. A country-level pooled estimate was used when ≥2 studies were available per country and geographic regional pooled estimates were used otherwise. The proportion of cases with a SOD1 or C9orf72 mutation among sporadic (sALS) and familial (fALS) cases were obtained from a previous systematic review and meta-analysis.

RESULTS

Pooled prevalence rates (per 100,000 persons) and incidence rates (per 100,000 person-years) were 6.22 and 2.31 for Europe, 5.20 and 2.35 for North America, 3.41 and 1.25 for Latin America, 3.01 and 0.93 for Asian countries excluding Japan, and 7.96 and 1.76 for Japan, respectively. Significant heterogeneity in reported incidence and prevalence was observed within and between countries/geographic regions. The estimated number of 2020 ALS cases across the 22 countries is 121,028 prevalent and 41,128 incident cases. The total estimated number of prevalent SOD1 cases is 2,876 cases, of which, 1,342 (47%) were fALS and 1,534 (53%) were sALS, and the number of incident SOD1 cases is 946 (434 [46%] fALS and 512 [54%] sALS). The total estimated number of prevalent C9orf72 cases is 4,545 (1,198 [26%] fALS, 3,347 [74%] sALS), and the number of incident C9orf72 cases is 1,706 (450 [26%] fALS and 1,256 [74%] sALS).

DISCUSSION

The estimated number of patients with SOD1 and C9orf72 ALS suggests that although the proportions of SOD1 and C9orf72 are higher among those with fALS, the majority of SOD1 and C9orf72 ALS cases may be found among those with sALS (about 53 and 74%, respectively). These results suggest that classification of fALS based on reported family history does not capture the full picture of ALS of genetic origin.

Clinical features and incidence trends of amyotrophic lateral sclerosis in Navarre, Spain, 2007-2018: a population-based study

Objective: Amyotrophic Lateral Sclerosis (ALS) is a heterogeneous neurodegenerative disorder with a median survival of 3 years. The aim of our study is to analyze the incidence, age-related phenotype and clinical onset, geographical distribution, survival and diagnostic delay of ALS in Navarre. Methods: This is a population-based observational retrospective study, including all residents of Navarre (a northern Spanish region) from 2007 to 2018, who were followed until 30th September 2020. Results: We observed a global incidence 2.47/100,000 person-years, with an upward trend throughout the study, with the highest being in the age group of 70-74 years old. Point prevalence in December 2018 was 6.64/100,000 inhabitants (95%CI: 4.52-8.45). Upper limbs weakness onset was the most frequent in young people (<60 years), and bulbar, lower limbs weakness, generalized and respiratory associated with older age. Bulbar phenotype is the most frequent in women and in 80+ group. The median survival from clinical onset was 27.7 months (95%CI: 24.0-31.4), higher in spinal phenotype and younger onset age, and the diagnosis delay was 10.0 months (95%CI: 8.9-11.2) from clinical onset. Conclusions: We have observed a trend of increasing incidence in older people where the bulbar phenotype and female predominance.

Otolaryngologist's role in the diagnosis of amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a progressive and late-onset fatal neurodegenerative disease characterised by selective death of motor neurons. The aetiology of ALS is still unknown and it is extremely heterogeneous in genetics and clinical presentation, being the respiratory failure the usual cause of death. We describe a case of a 61-year-old male patient referred to the otolaryngology consultation for a 6-month history of progressive solid dysphagia and dysphonia. The patient presented several voice alterations such as a dysarthric speech with hypernasal voice which evoked the hypothesis of a neuromuscular disease. That patient was observed by a neurologist and was submitted to an electromyography that confirmed the ALS diagnosis. This case highlights the key role of otolaryngologists in the diagnosis of ALS, in a way that many patients with a bulbar ALS form are initially studied by an otolaryngologist.

Early Referral to an ALS Center Reduces Several Months the Diagnostic Delay: A Multicenter-Based Study

Objective: To analyze those factors contributing to the diagnostic delay in ALS. Methods: Consecutive ALS patients were categorized as those studied in departmental hospitals and those studied in a referral ALS center. Demographic and clinical variables, together with data of the diagnostic pathway were collected. Multivariable models were used to assess their effect in the time between symptoms onset and the first neurologist visit (time symptoms-neurologist), in the time between the first neurologist visit and the diagnosis (time neurologist-diagnosis) and in the diagnostic delay. Results: 166 ALS patients with a median diagnostic delay of 11.53 months (IQR: 6.68, 15.23) were included. The median diagnostic delay was 8.57 months (5.16, 11.61) in the referral center vs. 12.08 months (6.87, 16.8) in departmental centers. Bulbar onset, fast progression rate, upper motor neuron predominant phenotype and an early referral to the neurologist were associated with a shorter time between symptoms-neurologist. Being studied in a referral center was associated with a shorter time between neurologist-diagnosis. Comorbidities, familial ALS, bulbar onset, early referral to the neurologist and being studied in a referral center were associated with a shorter diagnostic delay. For patients studied in departmental hospitals, fast progression rate was also strongly associated with a shorter time between neurologist-diagnosis and diagnostic delay. Conclusion: Unmodifiable factors (comorbidities, familial ALS, bulbar onset, and progression rate) as well as modifiable factors (early referral to the neurologist and the evaluation in an ALS referral center) have an independent effect in the diagnostic delay. The universalization of ALS Units is probably the most efficient measure to reduce the diagnostic delay.

Time to diagnosis and factors affecting diagnostic delay in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a progressive, degenerative neuromuscular disease with limited treatment options. The diagnosis of ALS can be challenging for numerous reasons, resulting in delays that may compromise optimal management and enrollment into clinical trials. Several studies have examined the process and challenges regarding the clinical diagnosis of ALS. Twenty-one studies that were almost exclusively from the English literature published between 1990 and 2020 were identified via PubMed using relevant search terms and included patient populations from the United States, Canada, Japan, Egypt, and several countries in South America and Europe. Probable or definitive ALS patients were identified using El Escorial or revised El Escorial/Airlie House Criteria. Time to diagnosis or diagnostic delay was defined as mean or median time from patient-reported first symptom onset to formal diagnosis by a physician, as recorded in medical records. The typical time to diagnosis was 10-16 months from symptom onset. Several points of delay in the diagnosis course were identified, including specialist referrals and misdiagnoses, often resulting in unnecessary procedures and surgeries. Bulbar onset was noted to significantly reduce time to ALS diagnosis. Future interventions and potential research opportunities were reviewed.

Amyotrophic lateral sclerosis care and research in the United States during the COVID-19 pandemic: Challenges and opportunities

Coronavirus disease 2019 has created unprecedented challenges for amyotrophic lateral sclerosis (ALS) clinical care and research in the United States. Traditional evaluations for making an ALS diagnosis, measuring progression, and planning interventions rely on in‐person visits that may now be unsafe or impossible. Evidence‐ and experience‐based treatment options, such as multidisciplinary team care, feeding tubes, wheelchairs, home health, and hospice, have become more difficult to obtain and in some places are unavailable. In addition, the pandemic has impacted ALS clinical trials by impairing the ability to obtain measurements for trial eligibility, to monitor safety and efficacy outcomes, and to dispense study drug, as these also often rely on in‐person visits. We review opportunities for overcoming some of these challenges through telemedicine and novel measurements. These can reoptimize ALS care and research in the current setting and during future events that may limit travel and face‐to‐face interactions.