Global, regional, and national burden of motor neuron diseases 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016

Amyotrophic lateral sclerosis in a tricenarian female

Amyotrophic lateral sclerosis (ALS) is a motor neuron disease characterized by the progressive degeneration of the upper and lower motor neurons. This disease is mostly observed in patients of the 6th decade or above, and it is extremely rare to observe this pathology in patients less than 50 years of age. This manuscript depicts the magnetic resonance imaging findings of ALS showing a wine glass sign in a 31-year-old female from a rural area with complaints of progressive limb weakness and muscle wasting.

Amyotrophic lateral sclerosis estimated prevalence cases from 2022 to 2030, data from the national ALS Registry

Objective: To estimate the projected number of ALS cases in the United States from 2022 to 2030. Amyotrophic lateral sclerosis (ALS) is a progressive and fatal neuromuscular disease with no known cure. Because ALS is not a notifiable disease in the United States, the accurate ascertainment of prevalent ALS cases continues to be a challenge. To overcome this, the National ALS Registry (Registry) uses novel methods to estimate newly diagnosed and existing cases in the United States. Methods: We estimated ALS prevalence retrospectively from 2022 to 2024 and prospectively from 2025 to 2030 using prevalence obtained through previous CRC analyses on 2018 Registry data (the most current data available) to generate projected observed, missing, and total cases. Projected prevalent cases were then stratified by age, race, and sex. Results: The number of estimated ALS cases in 2022 was 32,893. By 2030, projected cases increase more than 10%, to 36,308. The largest increase occurs for the population ages 66 years and older, with a 25% increase (from 16,349 cases in 2022 to 20,438 cases in 2030). The projected number of cases classified as "other race" will increase by 15% (from 2,473 cases in 2022 to 2,854 cases in 2030). Conclusions: These estimates of projected ALS cases reflect anticipated changes in the underlying demographics of the United States. Our projections are likely an underestimation because emerging therapeutics and improved healthcare will improve survivability in this vulnerable population. These results should inform policy to more efficiently allocate resources for ALS patients and programs.

Disability-Adjusted Life Years (DALYs) due to Breast, Cervical, Colorectal and Oral Cancers in Taiwan Regions

BACKGROUND

Cancer is a leading cause of death globally, with significant variations in incidence and mortality rates among different cancer types and regions. In Taiwan, breast cancer (BC), cervical cancer (CxCa), colorectal cancer (CRC), and oral cancer (OC) are prevalent and have prompted government-led screening programs to mitigate their impact. This study aims to assess the burden of these cancers at the county scale using disability-adjusted life years (DALYs) as a metric, focusing on the years 2010, 2015, 2018, 2019, and 2020.

METHODS

Data on cancer incidence, mortality, disability weights, and treatment outcomes were sourced from the Taiwan HPA, Ministry of Health and Welfare, and Taiwan Cancer Registry. Years of life lost (YLLs) and years lived with disability (YLDs) were calculated for each cancer, considering age, stage, and treatment. The correlation between cancer screening rates and disease burden also conducted.

RESULTS

The analysis highlights significant trends in cancer mortality, incidence, and disease burden in Taiwan from 2010 to 2020. BC and CRC showed rising ASMR and DALYs rates, while CxCa experienced consistent declines. OC had a fluctuating pattern, particularly in eastern regions. YLLs contributed significantly to DALYs for all cancers, emphasizing premature mortality's role in the disease burden. Screening rates, particularly for BC and CxCa, correlated with changes in burden, with BC rates increasing and CxCa decreasing, reflecting the impact of preventive measures on cancer outcomes.

CONCLUSIONS

The findings underscore the importance of targeted interventions and evidence-informed resource allocation to address regional differences in cancer burden in Taiwan.

Characterization, epidemiology, and factors associated with evolution and survival in patients with amyotrophic lateral sclerosis in southeastern Spain, 2008-2021: a population-based study

OBJECTIVE

To describe the epidemiology, characteristics, and factors associated with the evolution and survival in patients with amyotrophic lateral sclerosis (ALS) in a region of southeastern Spain.

METHODS

An observational study was carried out in people with a diagnosis of ALS in the period 2008-2021 who were registered in the Information System of Rare Diseases of the Region of Murcia (SIER). We calculated crude and standardized incidence rate (SIR) using European Standard Population of 2013 and point prevalence. The Kaplan-Meier method and the log-rank test were used to estimate and compare survival curves.

RESULTS

We identified 374 cases. The mean age at diagnosis was 66.5 ± 11.7 and 50.3% persons were spinal onset. Mean time from the onset of symptoms to diagnosis was 0.9 ± 1.0 years. The global SIR was 1.95/100,000 person-years (95%CI: 1.77-2.12), which was higher in men (ratio 1.34), and the point prevalence in 2021 was 4.57 per 100,000 (95% CI: 4.46-4.68). There were 297 deaths with a mean age of 69.8 ± 10.8. The median survival from clinical onset was 2 years (95%CI: 1.0-3.0). Factors associated with lower survival were bulbar onset (p < 0.001), older age at the onset of symptoms (p < 0.001), and the absence of riluzole treatment (p = 0.003).

CONCLUSIONS

This study is one of few to evaluate the epidemiological, characteristics, and prognostic factors of ALS in Spain, with findings similar to previous population studies. The use of population-based registries offers reliable information on the magnitude, or evolution in these patients.

Incidence and mortality of ALS: a 42-year population-based nationwide study

BACKGROUND AND AIM

Recent studies have suggested that the incidence rate (IR) and the rate of death (MR) of amyotrophic lateral sclerosis (ALS) are increasing. Still, it remains unclear whether this is due to improved case ascertainment or represents a true increase. We examined the development in the incidence and mortality of ALS in Denmark for 42 years.

METHODS

We retrieved individual-level data of all patients aged above 18 years with first-time ALS diagnosed at any Danish department of neurology. The IR and MR were calculated based on data from 1980 to 2021, stratified by gender and age.

RESULTS

We identified 5,943 patients with ALS and identified a total of 5,069 deaths in the nationwide population. Overall, the IR was 3.4 per 100,000 persons per year (95% CI 3.4-3.5). ALS incidence rose gradually during the study period, and the IR was 2.8 times higher (95% CI 2.4-3.2) when comparing the latest period (2018-2021) with the first (1980-1983). Parallel to the IR, the MR increased over time and was associated with male gender and rose with age at diagnosis, peaking in the 70-79-year age group.

CONCLUSION

In Denmark, the IR and MR of ALS increased threefold from 1980 to 2021, with steadily increasing risk related to male gender and in particular to higher age. Considering our aging societies, the number of elderly patients with ALS can be expected to increase considerably.

Machine learning and brain-computer interface approaches in prognosis and individualized care strategies for individuals with amyotrophic lateral sclerosis: A systematic review

Amyotrophic lateral sclerosis (ALS) characterized by progressive degeneration of motor neurons is a debilitating disease, posing substantial challenges in both prognosis and daily life assistance. However, with the advancement of machine learning (ML) which is renowned for tackling many real-world settings, it can offer unprecedented opportunities in prognostic studies and facilitate individuals with ALS in motor-imagery tasks. ML models, such as random forests (RF), have emerged as the most common and effective algorithms for predicting disease progression and survival time in ALS. The findings revealed that RF models had an excellent predictive performance for ALS, with a testing R2 of 0.524 and minimal treatment effects of 0.0717 for patient survival time. Despite significant limitations in sample size, with a maximum of 18 participants, which may not adequately reflect the population diversity being studied, ML approaches have been effectively applied to ALS datasets, and numerous prognostic models have been tested using neuroimaging data, longitudinal datasets, and core clinical variables. In many literatures, the constraints of ML models are seldom explicitly enunciated. Therefore, the main objective of this research is to provide a review of the most significant studies on the usage of ML models for analyzing ALS. This review covers a variation of ML algorithms involved in applications in ALS prognosis besides, leveraging ML to improve the efficacy of brain-computer interfaces (BCIs) for ALS individuals in later stages with restricted voluntary muscular control. The key future advances in individualized care and ALS prognosis may include the advancement of more personalized care aids that enable real-time input and ongoing validation of ML in diverse healthcare contexts.

Efficacy of pain management strategies in adults with Amyotrophic Lateral Sclerosis (ALS): A Systematic Review

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive muscle weakness. Presence of pain in ALS patients is heterogeneously reported in studies, and mostly underrepresented in symptom scales. The aim of this study is to evaluate the efficacy of pharmacological and non-pharmacological therapeutic modalities for pain management in patients with ALS. A systematic review was conducted in four databases; PubMed, Scopus, Clinicaltrials.gov, and Cochrane-Ovid. Five randomized controlled clinical trials were included regarding pharmacological and non-pharmacological pain management interventions in adult patients with confirmed diagnosis of ALS in whom pain was objectively evaluated. Risk of bias assessment was evaluated using the RoB2.0 tool. Eligible studies were reported as a descriptive analysis. This systematic review was registered with PROSPERO ID: CRD42024495009. Five clinical trials regarding pain management strategies in ALS were eligible for analysis. Two out of five were non-pharmacological approaches whilst the remaining three provided pharmacological therapies. Of these, Mexiletine was efficient in terms of pain relief, particularly between 600 and 900 mg per day, whereas Mecasin showed no pain relief at both, high and low doses. Non-pharmacological therapies, such as exercise and osteopathic manual treatment also lacked efficacy in regard to pain management. Clinical trials focusing on pain management strategies for ALS patients are limited. Medical professionals, understandably focused on immediate life-threatening aspects, may inadvertently sideline the nuanced and intricate dimension of pain experienced by patients with ALS.

Geographical, gender and age inequalities in non-communicable diseases both at national and provincial levels in Iran

Over 80% of deaths due to non-communicable diseases (NCDs) occur in low and middle-income countries, indicating an inequality in the health care system around the world. Conducted studies at provincial level in developed countries have shown that mortality rates due to this group of diseases are higher in the populations with lower education, income, and social class. NCDs account for 71.3% of total world deaths in 2016 and 79.2% of total deaths in Iran in the same year. Improving the health of Iranian population and reducing the number of communicable diseases over the past decades have made NCDs as a major health problem in Iran. In this study, we describe the status of most lethal NCDs in the country at national and provincial level. In addition, study on the inequality of deaths due to NCDs at provincial level in Iran showed that there is a considerable difference between different provinces. Furthermore, there is an age inequality so that mortality of main NCDs increased dramatically after the age of 70. Therefore, health policy makers and decision makers should adopt appropriate policies to reduce gender, geographic and age disparities to reduce gender and inter-provincial inequalities in Iran.

Air pollution exposure and mortality from neurodegenerative diseases in the Netherlands: A population-based cohort study

BACKGROUND

Long-term exposure to ambient air pollution has been linked with all-cause mortality and cardiovascular and respiratory diseases. Suggestive associations between ambient air pollutants and neurodegeneration have also been reported, but due to the small effect and relatively rare outcomes evidence is yet inconclusive. Our aim was to investigate the associations between long-term air pollution exposure and mortality from neurodegenerative diseases.

METHODS

A Dutch national cohort of 10.8 million adults aged ≥30 years was followed from 2013 until 2019. Annual average concentrations of air pollutants (ultra-fine particles (UFP), nitrogen dioxide (NO2), fine particles (PM2.5 and PM10) and elemental carbon (EC)) were estimated at the home address at baseline, using land-use regression models. The outcome variables were mortality due to amyotrophic lateral sclerosis (ALS), Parkinson's disease, non-vascular dementia, Alzheimer's disease, and multiple sclerosis (MS). Hazard ratios (HR) were estimated using Cox models, adjusting for individual and area-level socio-economic status covariates.

RESULTS

We had a follow-up of 71 million person-years. The adjusted HRs for non-vascular dementia were significantly increased for NO2 (1.03; 95% confidence interval (CI) 1.02-1.05) and PM2.5 (1.02; 95%CI 1.01-1.03) per interquartile range (IQR; 6.52 and 1.47 μg/m3, respectively). The association with PM2.5 was also positive for ALS (1.02; 95%CI 0.97-1.07). These associations remained positive in sensitivity analyses and two-pollutant models. UFP was not associated with any outcome. No association with air pollution was found for Parkinson's disease and MS. Inverse associations were found for Alzheimer's disease.

CONCLUSION

Our findings, using a cohort of more than 10 million people, provide further support for associations between long-term exposure to air pollutants (PM2.5 and particularly NO2) and mortality of non-vascular dementia. No associations were found for Parkinson and MS and an inverse association was observed for Alzheimer's disease.

Recognising dying in motor neurone disease: A scoping review

INTRODUCTION

Timely identification of dying in motor neurone disease enables optimal care, yet we know that healthcare professionals can fail to recognise when death is approaching. Clinical factors help predict the end of life in other terminal conditions. Examining these principles in motor neurone disease would help guide more accurate recognition of this critical phase.

AIM

To examine and map out what is known about dying in patients with motor neurone disease, and the recognition of dying by healthcare professionals.

DESIGN

A scoping review was conducted following the Arksey and O'Malley methodological framework.

DATA SOURCES

Four electronic databases (MEDLINE, Scopus, PsycINFO and CINAHL) and grey literature were searched on the 10th May 2023. Reference lists and citations were also reviewed.

RESULTS

From 1512 articles, 13 studies were included. Dyspnoea, anxiety and pain were the most common symptoms associated with the dying phase. Worsening respiratory function, the development of specific new symptoms and deteriorating symptom control suggested approaching death. No studies reported changes in vital signs or biomarkers associated with dying. Barriers to the recognition of dying by healthcare professionals included a rapid and unpredictable terminal decline.

CONCLUSIONS

Dying in motor neurone disease is associated with patterns of symptoms and signs, however evidence is limited compared with other terminal conditions and requires further exploration. The characteristic sudden and unpredictable terminal decline is a key barrier to recognition of dying by healthcare professionals. Optimising advance care planning is one approach to navigate these complex, unpredictable clinical situations.

A systematic review of studies that estimated the burden of chronic non-communicable rare diseases using disability-adjusted life years

BACKGROUND

Initiatives aiming to assess the impact of rare diseases on population health might be hampered due to the complexity of disability-adjusted life years (DALYs) estimation. This study aimed to give insight into the epidemiological data sources and methodological approaches used in studies that estimated DALYs for chronic non-communicable rare diseases (CNCRD), and compare its results.

METHODS

A literature strategy was developed for peer-review search in Embase and Medline, and also performed on grey literature databases and population health and/or rare disease-focused websites. We included studies that determined the burden of CNCRD listed on the Orphanet's and/or the Genetic and Rare Diseases information center (GARD) websites. We excluded communicable and occupational diseases, rare cancers, and cost-effectiveness/benefit studies. Two researchers independently screened the identified records and extracted data from the final included studies. We used the Guidelines for Accurate and Transparent Health Estimates Reporting (GATHER) statement to assess the quality of reporting of the included studies. The data synthesis depicted the studies' characteristics, their distribution by geographic coverage and the group of disease(s) they focused on, the methods and data input sources used and estimated DALY per case.

RESULTS

In total, 533 titles were screened, and 18 studies were included. These studies covered 19 different CNCRDs, of which most fell in the disease category "Diseases of the nervous system". Diverse methodological approaches and data input sources were observed among burden of CNCRD studies. A wide range of DALY per case was observed across the different studies and diseases included.

CONCLUSIONS

A low number of burden of CNCRD studies was observed and most estimates resulted from multi-country studies, underlining the importance of international cooperation to further CNCRD research. This study revealed a lack of epidemiological data and harmonization of methods which hampers comparisons across burden of CNCRD studies.

A Model-Based Economic Evaluation of Hypothetical Treatments for Amyotrophic Lateral Sclerosis in the UK: Implications for Pricing of New and Emerging Health Technologies

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a devastating disease which leads to loss of muscle function and paralysis. Historically, clinical drug development has been unsuccessful, but promising disease-modifying therapies (DMTs) may be on the horizon.

OBJECTIVES

The aims of this study were to estimate survival, quality-adjusted life-years (QALYs) and costs under current care, and to explore the conditions under which new therapies might be considered cost effective.

METHODS

We developed a health economic model to evaluate the cost effectiveness of future ALS treatments from a UK National Health Service and Personal Social Services perspective over a lifetime horizon using data from the ALS-CarE study. Costs were valued at 2021/22 prices. Two hypothetical interventions were evaluated: a DMT which delays progression and mortality, and a symptomatic therapy which improves utility only. Sensitivity analysis was conducted to identify key drivers of cost effectiveness.

RESULTS

Starting from King's stage 2, patients receiving current care accrue an estimated 2.27 life-years, 0.75 QALYs and lifetime costs of £68,047. Assuming a 50% reduction in progression rates and a UK-converted estimate of the price of edaravone, the incremental cost-effectiveness ratio for a new DMT versus current care is likely to exceed £735,000 per QALY gained. Symptomatic therapies may be more likely to achieve acceptable levels of cost effectiveness.

CONCLUSIONS

Regardless of efficacy, DMTs may struggle to demonstrate cost effectiveness, even at a low price. The cost effectiveness of DMTs is likely to be strongly influenced by drug price, the magnitude and durability of relative treatment effects, treatment starting/stopping rules and any additional utility benefits over current care.

Incidence of amyotrophic lateral sclerosis in Chile

OBJECTIVE

This study aimed to estimate amyotrophic lateral sclerosis (ALS) incidence and survival rates in the Metropolitan region of Chile.

METHODS

We conducted a cohort study of ALS cases in the Metropolitan Region from 2016 to 2019. A total of 219 ALS patients were recruited from Corporación ELA-Chile registry, in collaboration with neurologists from Sociedad de Neurología, Psiquiatría y Neurocirugía de Chile. We calculated incidence rates by sex and age and determined median survival from onset and diagnosis. Survival analysis used the Kaplan-Meier statistic, estimating hazard ratios for age, sex, time from symptom onset and from diagnosis using a Weibull regression model. All analyses were done using R 4.1.0.

RESULTS

Overall, ALS diagnosis incidence was 0.97 cases per 100,000 inhabitants, peaking in the 70-79 age group and declining thereafter. The male-to-female ratio was 1.23. The median time to death from diagnosis was 2.3 years (95% confidence interval [CI]: 1.9-2.5), and from the first symptom, it was 3.1 years (95% CI: 2.8-3.5).

CONCLUSIONS

This is the first population-based study reporting ALS incidence and survival rates in Chile's Metropolitan region. Incidence resembled other Latin American studies. Median survival from diagnosis and from the first symptom were in line with previous findings. Our results corroborated lower ALS rates in Latin America, consistent with prior research.

Incidence of amyotrophic lateral sclerosis before and during the COVID-19 pandemic: evidence from an 8-year population-based study in Central Italy based on healthcare utilization databases

BACKGROUND

Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disorder with a high multidimensional burden, with an obscure etiopathogenesis.

METHODS

We designed a longitudinal, population-based study of people residing in Central Italy (Marche Region) who were beneficiaries of the National Health System. People with an unprecedented ALS hospitalization (335.20 ICD-9 CM) or tagged with an ALS exemption between 2014 and 2021 were considered incident cases. ALS cases residing in the region for <3 years or with an active ALS exemption or hospitalized for ALS before 2014 were excluded. We used secondary sources to identify new ALS diagnoses. The regional referral center for ALS's database was used to test the accuracy of secondary sources in detecting cases. ALS mean incidence was compared to that reported in similar studies conducted in Italy. The incidence rate trend adjusted by sex and age was evaluated using the Poisson regression model.

RESULTS

We detected 425 new ALS cases (median age: 70y) in the 2014-2021 period, with a mean incidence of 3.5:100,000 py (95%CI: 3.2-3.8; M:F = 1.2), similar to that reported in similar studies conducted in Italy. No trend was observed during 2014-2019. After including 2020-2021 in the model, we observed a mean decrease in incidence of 5.8% (95% CI 2.0%; 9.5%, p = 0.003).

CONCLUSION

We show a decrease in the incidence rate of ALS in Marche, during the 2014-2021 period, as a possible outcome of a delayed neurological assessment and diagnosis during the pandemic. An ad hoc developed identification algorithm, based on healthcare utilization databases, is a valuable tool to assess the health impact of global contingencies.

Impact of Cognitive Impairment on Quality of Life in Multiple Sclerosis Patients-A Comprehensive Review

Multiple sclerosis (MS) is characterized by a variety of symptoms that have a major impact on quality of life (QoL) even in early stages. In addition to individual motor, sensory, visual disturbances, and brainstem and sphincter disorders, which are expressed through the widely used Expanded Disability Status Scale (EDSS), other manifestations of MS have a detrimental effect on overall functioning and quality of life, such as cognitive impairment, depression, anxiety, fatigue, and pain. However, when talking about QoL, categorical definitions cannot be used because although the concept is generally understood, it is highly nuanced. Suffering from MS can significantly reduce QoL. Numerous research studies have focused on trying to identify and assess which are the elements that most affect the loss of QoL in MS people. However, in addition to the fact that the measurement of QoL can be subjective, it is very difficult to consider these elements in isolation, as they are interrelated. One such limiting factor of QoL that has been investigated is cognitive impairment (CI). This has been shown to have an impact on the lives of MS people, although the different approaches that have been taken to assess CI have evident limitations.

Acceptance and Commitment Therapy plus usual care for improving quality of life in people with motor neuron disease (COMMEND): a multicentre, parallel, randomised controlled trial in the UK

BACKGROUND

Motor neuron disease is a progressive, fatal neurodegenerative disease for which there is no cure. Acceptance and Commitment Therapy (ACT) is a psychological therapy incorporating acceptance, mindfulness, and behaviour change techniques. We aimed to evaluate the effectiveness of ACT plus usual care, compared with usual care alone, for improving quality of life in people with motor neuron disease.

METHODS

We conducted a parallel, multicentre, two-arm randomised controlled trial in 16 UK motor neuron disease care centres or clinics. Eligible participants were aged 18 years or older with a diagnosis of definite or laboratory-supported probable, clinically probable, or possible familial or sporadic amyotrophic lateral sclerosis; progressive muscular atrophy; or primary lateral sclerosis; which met the World Federation of Neurology's El Escorial diagnostic criteria. Participants were randomly assigned (1:1) to receive up to eight sessions of ACT adapted for people with motor neuron disease plus usual care or usual care alone by a web-based system, stratified by site. Participants were followed up at 6 months and 9 months post-randomisation. Outcome assessors and trial statisticians were masked to treatment allocation. The primary outcome was quality of life using the McGill Quality of Life Questionnaire-Revised (MQOL-R) at 6 months post-randomisation. Primary analyses were multi-level modelling and modified intention to treat among participants with available data. This trial was pre-registered with the ISRCTN Registry (ISRCTN12655391).

FINDINGS

Between Sept 18, 2019, and Aug 31, 2022, 435 people with motor neuron disease were approached for the study, of whom 206 (47%) were assessed for eligibility, and 191 were recruited. 97 (51%) participants were randomly assigned to ACT plus usual care and 94 (49%) were assigned to usual care alone. 80 (42%) of 191 participants were female and 111 (58%) were male, and the mean age was 63·1 years (SD 11·0). 155 (81%) participants had primary outcome data at 6 months post-randomisation. After controlling for baseline scores, age, sex, and therapist clustering, ACT plus usual care was superior to usual care alone for quality of life at 6 months (adjusted mean difference on the MQOL-R of 0·66 [95% CI 0·22-1·10]; d=0·46 [0·16-0·77]; p=0·0031). Moderate effect sizes were clinically meaningful. 75 adverse events were reported, 38 of which were serious, but no adverse events were deemed to be associated with the intervention.

INTERPRETATION

ACT plus usual care is clinically effective for maintaining or improving quality of life in people with motor neuron disease. As further evidence emerges confirming these findings, health-care providers should consider how access to ACT, adapted for the specific needs of people with motor neuron disease, could be provided within motor neuron disease clinical services.

FUNDING

National Institute for Health and Care Research Health Technology Assessment and Motor Neurone Disease Association.

Increased incidence of motor neuron disease in Sweden: a population-based study during 2002-2021

BACKGROUND

Motor neuron diseases (MND), with amyotrophic lateral sclerosis constituting most cases, are rare conditions of unknown etiology. There have been reports of an increase in incidence during the latter half of the twentieth century in various Western countries, including Sweden. This study provides updated data on the incidence of MND in Sweden during the last 20 years.

METHODS

Data was obtained from the Swedish National Patient Register on individuals diagnosed with MND from 2002 to 2021 and analysed in relation to group level data for the entire Swedish population. Incidence rates were calculated and presented in relation to year, age, sex, and region.

RESULTS

In the early 2000s, there was a crude incidence rate of 3.5-3.7 per 100,000 person-years, which then increased to 4.0-4.6 from 2008 onward. Age standardization to the starting year (2002) partially mitigated this increase. The incidence rate was greater among men compared to women and was highest within the age range of 70 to 84 years. There were indications of a higher incidence rate in the northernmost parts of the country, although the difference was not statistically significant.

CONCLUSIONS

The incidence rate of MND in Sweden now seems to have surpassed 4 cases per 100,000 person-years. This is higher when compared to both other European countries and previous Swedish studies. It remains to be determined if this increase reflects an actual increasing incidence of MND in Sweden or is due to other factors such as better registry coverage.

Geographical distribution of clinical trials in amyotrophic lateral sclerosis: a scoping review

Introduction: Clinical trials location is determined by many factors, including the availability of patient populations, regulatory environment, scientific expertise, and cost considerations. In clinical drug development of amyotrophic lateral sclerosis (ALS), where genetic differences have been described and may be related to geographic setting, this could have implications for the clinical interpretation of results in underrepresented geographic settings. Objective: The aim of this study was to review country participation in ALS clinical research based on available data from clinical trial registries and databases. Methods: We performed a scoping review with available information about clinical trials on ALS in ClinicalTrials.gov (CT), EU clinical trials register (EudraCT), WHO International Clinical Trials Registry Platform (ICTRP) and Web of Science (WOS). Inclusion criteria were clinical trials in phase 2 and 3 to treat ALS, recruiting or active not recruiting, from 23/06/2018 to 23/06/2023. Results: The total number of clinical trials identified were 188; 54 studies in CT, 38 in EudraCT, 47 in ICTRP and 49 in WOS. We identified 77 clinical trials after deleting duplicates and applying exclusion criteria. The countries with most studies conducted were the US with 35 studies (10.9%), followed by the United Kingdom, Belgium, France and Germany with 21 studies each one of them (6.5%). Conclusion: The data obtained in our review showed a non-homogeneous distribution in clinical trials at the international level, which may influence the interpretation of the results obtained.

Clinical biomarker-based biological ageing and future risk of neurological disorders in the UK Biobank

BACKGROUND

Many common neurological disorders are associated with advancing chronological age, but their association with biological age (BA) remains poorly understood.

METHODS

We studied 325 870 participants in the UK Biobank without a diagnosed neurological condition at baseline and generated three previously-described measures of BA based on 18 routinely measured clinical biomarkers (PhenoAge, Klemera-Doubal method age (KDMAge), homeostatic dysregulation age). Using survival models, we assessed the effect of advanced BA on incident neurological diagnoses, including all-cause and cause-specific dementia, ischaemic stroke, Parkinson's disease and motor neuron disease.

RESULTS

During a mean follow-up of 9.0 years, there were 1397 incident cases of dementia and 2515 of ischaemic stroke, with smaller case numbers of other diagnoses. The strongest associations with a 1 SD in BA residual were seen for all-cause dementia (KDMAge HR=1.19, 95% CI=1.11 to 1.26), vascular dementia (1.41, 1.25 to 1.60) and ischaemic stroke (1.39, 1.34 to 1.46). Weaker associations were seen for Alzheimer's disease and motor neuron disease, while, in contrast, HRs for Parkinson's disease tended to be <1. Results were largely consistent after adjustment for disease-specific covariates including common cardiometabolic risk factors.

CONCLUSIONS

Advanced BA calculated from routine clinical biomarker results increases the risk of subsequent neurological diagnoses including all-cause dementia and ischaemic stroke.

LAENALS: epidemiological and clinical features of amyotrophic lateral sclerosis in Latin America

OBJECTIVE

The Latin American Epidemiologic study of ALS (LAENALS) aims to gather data on ALS epidemiology, phenotype, and risk factors in Cuba, Chile, and Uruguay, to understand the impact of genetic and environmental factors on ALS.

METHODS

A harmonized data collection protocol was generated, and a Latin-American Spanish language Register was constructed. Patient data were collected in Uruguay in 2018, in Chile from 2017 to 2019, and in Cuba between 2017 and 2018. Statistical analysis was performed using SPSS 25.0.0 software. Crude cumulative incidence, standardized incidence, and prevalence were calculated in the population aged 15 years and older.

RESULTS

During 2017-2019, 90 people with ALS from Uruguay (55.6% men), 219 from Chile (54.6% men), and 49 from Cuba (55.1% men) were included. The cumulative crude incidence in 2018 was 1.73/100,000 persons in Uruguay, 1.08 in Chile and 0.195 in Cuba. Crude prevalence in 2018 was 2.19 per 100,000 persons in Uruguay, 1.39 in Chile and 0.55 in Cuba. Mean age at onset was 61.8 ± 11.96 SD years in Uruguay, 61.9 ± 10.4 SD years in Chile, and 60.21 ± 12.45 SD years in Cuba (p = 0.75). Median survival from onset was 32.43 months (21.93 - 42.36) in Uruguay, 24 months (13.5 - 33.5) in Chile, and 29 months (15 - 42.5) in Cuba (p = 0.006).

CONCLUSIONS

These preliminary data from LAENALS confirm the lower incidence and prevalence of ALS in counties with admixed populations. The LAENALS database is now open to other Latin American countries for harmonized prospective data collection.

Genetic analyses identify brain imaging-derived phenotypes associated with the risk of amyotrophic lateral sclerosis

Brain imaging-derived phenotypes have been suggested to be associated with amyotrophic lateral sclerosis in observational studies, but whether these associations are causal remains unclear. We aimed to assess the potential bidirectional causal associations between imaging-derived phenotypes and amyotrophic lateral sclerosis using bidirectional 2-sample Mendelian randomization analyses. Summary statistics for 469 imaging-derived phenotypes (33,224 individuals) and amyotrophic lateral sclerosis (20,806 cases and 59,804 controls) were obtained from 2 large-scale genome-wide association studies of European ancestry. We used the inverse-variance weighted Mendelian randomization method in the main analysis to assess the bidirectional associations between imaging-derived phenotypes and amyotrophic lateral sclerosis, followed by several sensitivity analyses for robustness validation. In the forward Mendelian randomization analyses, we found that genetically determined high orientation dispersion index in the right cerebral peduncle was associated with the increased risk of amyotrophic lateral sclerosis (odds ratio = 1.30, 95% confidence interval = 1.16-1.45, P = 2.26 × 10-6). In addition, the reverse Mendelian randomization analysis indicated that amyotrophic lateral sclerosis had no effect on 469 imaging-derived phenotypes. Mendelian randomization-Egger regression analysis showed no directional pleiotropy for the association between high orientation dispersion index in the right cerebral peduncle and amyotrophic lateral sclerosis, and sensitivity analyses with different Mendelian randomization models further confirmed these findings. The present systematic bidirectional Mendelian randomization analysis showed that high orientation dispersion index in the right cerebral peduncle might be the potential causal mediator of amyotrophic lateral sclerosis, which may provide predictive guidance for the prevention of amyotrophic lateral sclerosis. Further studies are warranted to replicate our findings and clarify the underlying mechanisms.

Machine learning hypothesis-generation for patient stratification and target discovery in rare disease: our experience with Open Science in ALS

Introduction

Advances in machine learning (ML) methodologies, combined with multidisciplinary collaborations across biological and physical sciences, has the potential to propel drug discovery and development. Open Science fosters this collaboration by releasing datasets and methods into the public space; however, further education and widespread acceptance and adoption of Open Science approaches are necessary to tackle the plethora of known disease states.

Motivation

In addition to providing much needed insights into potential therapeutic protein targets, we also aim to demonstrate that small patient datasets have the potential to provide insights that usually require many samples (>5,000). There are many such datasets available and novel advancements in ML can provide valuable insights from these patient datasets.

Problem statement

Using a public dataset made available by patient advocacy group AnswerALS and a multidisciplinary Open Science approach with a systems biology augmented ML technology, we aim to validate previously reported drug targets in ALS and provide novel insights about ALS subpopulations and potential drug targets using a unique combination of ML methods and graph theory.

Methodology

We use NetraAI to generate hypotheses about specific patient subpopulations, which were then refined and validated through a combination of ML techniques, systems biology methods, and expert input.

Results

We extracted 8 target classes, each comprising of several genes that shed light into ALS pathophysiology and represent new avenues for treatment. These target classes are broadly categorized as inflammation, epigenetic, heat shock, neuromuscular junction, autophagy, apoptosis, axonal transport, and excitotoxicity. These findings are not mutually exclusive, and instead represent a systematic view of ALS pathophysiology. Based on these findings, we suggest that simultaneous targeting of ALS has the potential to mitigate ALS progression, with the plausibility of maintaining and sustaining an improved quality of life (QoL) for ALS patients. Even further, we identified subpopulations based on disease onset.

Conclusion

In the spirit of Open Science, this work aims to bridge the knowledge gap in ALS pathophysiology to aid in diagnostic, prognostic, and therapeutic strategies and pave the way for the development of personalized treatments tailored to the individual's needs.

Selective vulnerability of motor neuron types and functional groups to degeneration in amyotrophic lateral sclerosis: review of the neurobiological mechanisms and functional correlates

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative condition characterised by a progressive loss of motor neurons controlling voluntary muscle activity. The disease manifests through a variety of motor dysfunctions related to the extent of damage and loss of neurons at different anatomical locations. Despite extensive research, it remains unclear why some motor neurons are especially susceptible to the disease, while others are affected less or even spared. In this article, we review the neurobiological mechanisms, neurochemical profiles, and morpho-functional characteristics of various motor neuron groups and types of motor units implicated in their differential exposure to degeneration. We discuss specific cell-autonomous (intrinsic) and extrinsic factors influencing the vulnerability gradient of motor units and motor neuron types to ALS, with their impact on disease manifestation, course, and prognosis, as revealed in preclinical and clinical studies. We consider the outstanding challenges and emerging opportunities for interpreting the phenotypic and mechanistic variability of the disease to identify targets for clinical interventions.

Pathomechanistic Networks of Motor System Injury in Amyotrophic Lateral Sclerosis

Amyotrophic Lateral Sclerosis (ALS) is the most common, adult-onset, progressive motor neurodegenerative disorder that results in death within 3 years of the clinical diagnosis. Due to the clinicopathological heterogeneity, any reliable biomarkers for diagnosis or prognosis of ALS have not been identified till date. Moreover, the only three clinically approved treatments are not uniformly effective in slowing the disease progression. Over the last 15 years, there has been a rapid advancement in research on the complex pathomechanistic landscape of ALS that has opened up new avenues for successful clinical translation of targeted therapeutics. Multiple studies suggest that the age-dependent interaction of risk-associated genes with environmental factors and endogenous modifiers is critical to the multi-step process of ALS pathogenesis. In this review, we provide an updated discussion on the dysregulated cross-talk between intracellular homeostasis processes, the unique molecular networks across selectively vulnerable cell types, and the multisystemic nature of ALS pathomechanisms. Importantly, this work highlights the alteration in epigenetic and epitranscriptomic landscape due to gene-environment interactions, which have been largely overlooked in the context of ALS pathology. Finally, we suggest that precision medicine research in ALS will be largely benefitted from the stratification of patient groups based on the clinical phenotype, onset and progression, genome, exposome, and metabolic identities.

Metformin: The Winding Path from Understanding Its Molecular Mechanisms to Proving Therapeutic Benefits in Neurodegenerative Disorders

Metformin, a widely prescribed medication for type 2 diabetes, has garnered increasing attention for its potential neuroprotective properties due to the growing demand for treatments for Alzheimer's, Parkinson's, and motor neuron diseases. This review synthesizes experimental and clinical studies on metformin's mechanisms of action and potential therapeutic benefits for neurodegenerative disorders. A comprehensive search of electronic databases, including PubMed, MEDLINE, Embase, and Cochrane library, focused on key phrases such as "metformin", "neuroprotection", and "neurodegenerative diseases", with data up to September 2023. Recent research on metformin's glucoregulatory mechanisms reveals new molecular targets, including the activation of the LKB1-AMPK signaling pathway, which is crucial for chronic administration of metformin. The pleiotropic impact may involve other stress kinases that are acutely activated. The precise role of respiratory chain complexes (I and IV), of the mitochondrial targets, or of the lysosomes in metformin effects remains to be established by further research. Research on extrahepatic targets like the gut and microbiota, as well as its antioxidant and immunomodulatory properties, is crucial for understanding neurodegenerative disorders. Experimental data on animal models shows promising results, but clinical studies are inconclusive. Understanding the molecular targets and mechanisms of its effects could help design clinical trials to explore and, hopefully, prove its therapeutic effects in neurodegenerative conditions.

Estimated Familial Amyotrophic Lateral Sclerosis Proportion: A Literature Review and Meta-analysis

Background and Objectives

Amyotrophic lateral sclerosis (ALS) is a rare neurodegenerative disorder. Familial (fALS) cases are usually reported to constitute 5%-10% of all ALS cases; however, no recent literature review or meta-analysis of this proportion (referred to throughout as "proportion fALS") has been conducted. Our objective was to estimate the proportion fALS by geographic region and to assess the effect of study characteristics on the estimates.

Methods

A comprehensive literature review was performed to identify all original studies reporting the number of fALS cases in an ALS cohort. The results were stratified by geographic region, study design (case series or population-based), and decade of study publication. Subgroup analyses were conducted according to family history criteria used to define fALS. We report pooled estimates of the proportion fALS from random-effects meta-analyses when >2 studies are available and I2 is < 90%; weighted averages and ranges are otherwise presented.

Results

The overall pooled proportion fALS based on a total 165 studies was 8% (0%, 71%). The proportion fALS was 9% (0%, 71%) among 107 case series and 5% (4%, 6%) among 58 population-based studies. Among population-based studies, proportion fALS by geographic region was 6% (5%, 7%; N = 37) for Europe, 5% (3%, 7%; N = 5) for Latin America, and 5% (4%, 7%; N = 12) for North America. Criteria used to define fALS were reported by 21 population-based studies (36%), and proportion fALS was 5% (4%, 5%; N = 9) for first-degree relative, 7% (4%, 11%; N = 4) for first or second-degree relative, and 11% (N = 1) for more distant ALS family history. Population-based studies published in the 2000s or earlier generated a lower pooled proportion fALS than studies published in the 2010s or later.

Discussion

The results suggest that variability in the reported proportion fALS in the literature may be, in part, due to the differences in geography, study design, fALS definition, and decade of case ascertainment. Few studies outside of European ancestral populations were available. The proportion fALS was marginally higher among case series compared with population-based studies, likely because of referral bias. Criteria used to define fALS were largely unreported. Consensus criteria for fALS and additional population-based studies in non-European ancestral populations are needed.

Progranulin and GPNMB: interactions in endo-lysosome function and inflammation in neurodegenerative disease

BACKGROUND

Alterations in progranulin (PGRN) expression are associated with multiple neurodegenerative diseases (NDs), including frontotemporal dementia (FTD), Alzheimer's disease (AD), Parkinson's disease (PD), and lysosomal storage disorders (LSDs). Recently, the loss of PGRN was shown to result in endo-lysosomal system dysfunction and an age-dependent increase in the expression of another protein associated with NDs, glycoprotein non-metastatic B (GPNMB).

MAIN BODY

It is unclear what role GPNMB plays in the context of PGRN insufficiency and how they interact and contribute to the development or progression of NDs. This review focuses on the interplay between these two critical proteins within the context of endo-lysosomal health, immune function, and inflammation in their contribution to NDs.

SHORT CONCLUSION

PGRN and GPNMB are interrelated proteins that regulate disease-relevant processes and may have value as therapeutic targets to delay disease progression or extend therapeutic windows.

CRISPR/Cas9 Directed Reprogramming of iPSC for Accelerated Motor Neuron Differentiation Leads to Dysregulation of Neuronal Fate Patterning and Function

Neurodegeneration causes a significant disease burden and there are few therapeutic interventions available for reversing or slowing the disease progression. Induced pluripotent stem cells (iPSCs) hold significant potential since they are sourced from adult tissue and have the capacity to be differentiated into numerous cell lineages, including motor neurons. This differentiation process traditionally relies on cell lineage patterning factors to be supplied in the differentiation media. Genetic engineering of iPSC with the introduction of recombinant master regulators of motor neuron (MN) differentiation has the potential to shorten and streamline cell developmental programs. We have established stable iPSC cell lines with transient induction of exogenous LHX3 and ISL1 from the Tet-activator regulatory region and have demonstrated that induction of the transgenes is not sufficient for the development of mature MNs in the absence of neuron patterning factors. Comparative global transcriptome analysis of MN development from native and Lhx-ISL1 modified iPSC cultures demonstrated that the genetic manipulation helped to streamline the neuronal patterning process. However, leaky gene expression of the exogenous MN master regulators in iPSC resulted in the premature activation of genetic pathways characteristic of the mature MN function. Dysregulation of metabolic and regulatory pathways within the developmental process affected the MN electrophysiological responses.

A Hyperflexible Electrode Array for Long-Term Recording and Decoding of Intraspinal Neuronal Activity

Neural interfaces for stable access to the spinal cord (SC) electrical activity can benefit patients with motor dysfunctions. Invasive high-density electrodes can directly extract signals from SC neuronal populations that can be used for the facilitation, adjustment, and reconstruction of motor actions. However, developing neural interfaces that can achieve high channel counts and long-term intraspinal recording remains technically challenging. Here, a biocompatible SC hyperflexible electrode array (SHEA) with an ultrathin structure that minimizes mechanical mismatch between the interface and SC tissue and enables stable single-unit recording for more than 2 months in mice is demonstrated. These results show that SHEA maintains stable impedance, signal-to-noise ratio, single-unit yield, and spike amplitude after implantation into mouse SC. Gait analysis and histology show that SHEA implantation induces negligible behavioral effects and Inflammation. Additionally, multi-unit signals recorded from the SC ventral horn can predict the mouse's movement trajectory with a high decoding coefficient of up to 0.95. Moreover, during step cycles, it is found that the neural trajectory of spikes and low-frequency local field potential (LFP) signal exhibits periodic geometry patterns. Thus, SHEA can offer an efficient and reliable SC neural interface for monitoring and potentially modulating SC neuronal activity associated with motor dysfunctions.

Mitochondria, a Key Target in Amyotrophic Lateral Sclerosis Pathogenesis

Mitochondrial dysfunction occurs in numerous neurodegenerative diseases, particularly amyotrophic lateral sclerosis (ALS), where it contributes to motor neuron (MN) death. Of all the factors involved in ALS, mitochondria have been considered as a major player, as secondary mitochondrial dysfunction has been found in various models and patients. Abnormal mitochondrial morphology, defects in mitochondrial dynamics, altered activities of respiratory chain enzymes and increased production of reactive oxygen species have been described. Moreover, the identification of CHCHD10 variants in ALS patients was the first genetic evidence that a mitochondrial defect may be a primary cause of MN damage and directly links mitochondrial dysfunction to the pathogenesis of ALS. In this review, we focus on the role of mitochondria in ALS and highlight the pathogenic variants of ALS genes associated with impaired mitochondrial functions. The multiple pathways demonstrated in ALS pathogenesis suggest that all converge to a common endpoint leading to MN loss. This may explain the disappointing results obtained with treatments targeting a single pathological process. Fighting against mitochondrial dysfunction appears to be a promising avenue for developing combined therapies in the future.

Palliative Care in Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disease of the motor neurons. Given the evolutive characteristics of this disease, palliative care principles should be a foundation of ALS care. A multidisciplinary medical intervention is of paramount importance in the different phases of disease. The involvement of the palliative care team improves quality of life and symptoms, and prognosis. Early initiation is of paramount importance to ensuring patient-centered care, when the patient has still the capability to communicate effectively and participate in his medical care. Advance care planning supports patients and family members in understanding and sharing their preferences according to their personal values and life goals regarding future medical treatment. The principal problems which require intensive supportive care include cognitive disturbances, psychological distress, pain, sialorrhrea, nutrition, and ventilatory support. Communication skills of health-care professionals are mandatory to manage the inevitability of death. Palliative sedation has peculiar aspects in this population, particularly with the decision of withdrawing ventilatory support.

Sodium butyrate does not protect spinal motor neurons from AMPA-induced excitotoxic degeneration in vivo

Motor neuron (MN) loss is the primary pathological hallmark of amyotrophic lateral sclerosis (ALS). Histone deacetylase 4 (HDAC4) is one of several factors involved in nerve-muscle communication during MN loss, hindering muscle reinnervation, as shown in humans and in animal models of ALS, and may explain the differential progression observed in patients with ALS - rapid versus slow progression. In this work, we inhibited HDAC4 activity through the administration of a pan-histone deacetylase inhibitor, sodium butyrate, in an in vivo model of chronic spinal MN death induced by AMPA-mediated excitotoxicity. We infused AMPA into the spinal cord at low and high doses, which mimic the rapid and slow progression observed in humans, respectively. We found that muscle HDAC4 expression was increased by high-dose infusion of AMPA. Treatment of animals with sodium butyrate further decreased expression of muscle HDAC4, although non-significantly, and did not prevent the paralysis or the MN loss induced by AMPA infusion. These results inform on the role of muscle HDAC4 in MN degeneration in vivo and provide insights for the search for more suitable therapeutic strategies.

C9ORF72 Gene GGGGCC Hexanucleotide Expansion: A High Clinical Variability from Amyotrophic Lateral Sclerosis to Frontotemporal Dementia

The expanded GGGGCC hexanucleotide repeat (HRE) in the non-coding region of the C9ORF72 gene (C9ORF72-HRE) is the most common genetic cause of familial forms of amyotrophic lateral sclerosis (ALS), FTD, and concurrent ALS and FTD (ALS-FTD), in addition to contributing to the sporadic forms of these diseases. Both syndromes overlap not only genetically, but also sharing similar clinical and neuropathological findings, being considered as a spectrum. In this paper we describe the clinical-genetic findings in a Basque family with different manifestations within the spectrum, our difficulties in reaching the diagnosis, and a narrative review, carried out as a consequence, of the main features associated with C9ORF72-HRE. Family members underwent a detailed clinical assessment, neurological examination, and genetic analysis by repeat-primed PCR. We studied 10 relatives of a symptomatic carrier of the C9ORF72-HRE expansion. Two of them presented the expansion in the pathological range, one of them was symptomatic whereas the other one remained asymptomatic at 72 years. Given the great intrafamilial clinical variability of C9ORF72-HRE, the characterization of patients and family members with particular clinical and genetic subgroups within ALS and FTD becomes a bottleneck for medication development, in particular for genetically focused medicines for ALS and FTD.

Neurological disorders and disability in Pakistan: A cross-sectional multicenter study

BACKGROUND/OBJECTIVE

The aim of this study is to identify frequencies of various neurological disorders (NDs) and associated disability in patients attending neurologic clinics in rural and urban centers in Pakistan.

METHODS

This is an observational study conducted in 39 neurological centers in both rural and urban areas, public and private health sectors all over Pakistan. This study was conducted between august 2017 to December 2019.

RESULTS

A total of 28,845 adults were enrolled. Mean age of the study participants was 46.2 ± 17.2 years, 15,252 (52.9%) were men and 13,593 (47.1%) were women. Most common comorbid medical condition was hypertension 7622(26.4%) followed by Diabetes 3409(11.8%). Among neurological diagnoses, vascular diseases (20%) were the most common followed by Headache disorders (18.6%), Epilepsy (12.5%), nerve and root diseases (12.4%), Psychiatric diseases (10%), Dementias (8%) and movement disorders (7.9%). Half of the patients 15,503(53.7%) had no neurological disability, while minor disability was present in 10,442(36.2%) of cases. Moderate to severe disability was present in 2876(10%) cases. Headache disorders, psychiatric diseases, muscle pain/muscle related disorders and demyelinating diseases were more common in women. Vascular diseases, movement disorders and Dementias were more common in 46 years and above age group whereas headache disorders, Epilepsy and Psychiatric disorders were more prevalent in <46 years age groups.

CONCLUSION

Vascular diseases are the most common presentation of patients in neurology clinics followed by headache disorders and epilepsies. Minor disability was present in 36% while moderate to severe disability was present in 10% cases.

Global Prevalence and Incidence of Amyotrophic Lateral Sclerosis: A Systematic Review

BACKGROUND AND OBJECTIVES

Amyotrophic lateral sclerosis (ALS) is a rare neurodegenerative disorder affecting upper and lower motor neurons. Due to its rarity and rapidly progressive nature, studying the epidemiology of ALS is challenging, and a comprehensive picture of the global burden of this disease is lacking. The objective of this systematic review was to describe the global incidence and prevalence of ALS.

METHODS

We searched MEDLINE, Embase, Global Health, PsycInfo, Cochrane Library, and CINAHL to identify articles published between January 1, 2010, and May 6, 2021. Studies that were population based and reported estimates of prevalence, incidence, and/or mortality of ALS were eligible for inclusion. This study focuses on the incidence and prevalence. Quality assessment was performed using a tool developed to evaluate methodology relevant to prevalence and incidence studies. This review was registered with PROSPERO, CRD42021250559.

RESULTS

This search generated 6,238 articles, of which 140 were selected for data extraction and quality assessment. Of these, 85 articles reported on the incidence and 61 on the prevalence of ALS. Incidence ranged from 0.26 per 100,000 person-years in Ecuador to 23.46 per 100,000 person-years in Japan. Point prevalence ranged from 1.57 per 100,000 in Iran to 11.80 per 100,000 in the United States. Many articles identified cases with ALS from multiple data sources.

DISCUSSION

There is variation in reported incidence and prevalence estimates of ALS across the world. While registries are an important and powerful tool to quantify disease burden, such resources are not available everywhere. This results in gaps in reporting of the global epidemiology of ALS, as highlighted by the degree of variation (and quality) in estimates of incidence and prevalence reported in this review.

Motor cortex hemodynamic response to goal-oriented and non-goal-oriented tasks in healthy subjects

Background

Motor disorders are one of the world's major scourges, and neuromotor rehabilitation is paramount for prevention and monitoring plans. In this scenario, exercises and motor tasks to be performed by patients are crucial to follow and assess treatments' progression and efficacy. Nowadays, in clinical environments, quantitative assessment of motor cortex activities during task execution is rare, due to the bulkiness of instrumentation and the need for immobility during measurements [e.g., functional magnetic resonance imaging (MRI)]. Functional near-infrared spectroscopy (fNIRS) can contribute to a better understanding of how neuromotor processes work by measuring motor cortex activity non-invasively in freely moving subjects.

Aim

Exploit fNIRS to measure functional activation of the motor cortex area during arm-raising actions.

Design

All subjects performed three different upper limbs motor tasks: arm raising (non-goal-oriented), arm raising and grasping (goal oriented), and assisted arm raising (passive task). Each task was repeated ten times. The block design for each task was divided into 5 seconds of baseline, 5 seconds of activity, and 15 seconds of recovery.

Population

Sixteen healthy subjects (11 males and 5 females) with an average (+/- standard deviation) of 37.9 (+/- 13.0) years old.

Methods

Cerebral hemodynamic responses have been recorded in two locations, motor cortex (activation area) and prefrontal cortex (control location) exploiting commercial time-domain fNIRS devices. Haemodynamic signals were analyzed, separating the brain cortex hemodynamic response from extracerebral hemodynamic variations.

Results

The hemodynamic response was recorded in the cortical motor area for goal-oriented and not-goaloriented tasks, while no response was noticed in the control location (prefrontal cortex position).

Conclusions

This study provides a basis for canonical upper limb motor cortex activations that can be potentially compared to pathological cerebral responses in patients. It also highlights the potential use of TD-fNIRS to study goal-oriented versus non-goaloriented motor tasks. Impact: the findings of this study may have implications for clinical rehabilitation by providing a better understanding of the neural mechanisms underlying goal-oriented versus non-goal-oriented motor tasks. This may lead to more effective rehabilitation strategies for individuals with motor disorders and a more effective diagnosis of motor dysfunction supported by objective and quantitative neurophysiological readings.

Analysis of the spatial distribution of amyotrophic lateral sclerosis in Virginia

Objective: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder that is usually fatal. Environmental exposures have been posited in the etiology of ALS, but few studies have modeled the spatial risk of ALS over large geographic areas. In this paper, our goal was to analyze the spatial distribution of ALS in Virginia and identify any areas with significantly elevated risk using Virginia ALS Association administrative data. Methods: We used Bayesian hierarchical spatial regression models to estimate the relative risk for ALS in Virginia census tracts, adjusting for several covariates posited to be associated with the disease. We used an intrinsic conditional autoregressive prior to allow for spatial correlation in the risk estimates and stabilize estimates over space. Results: Considerable variation in ALS risk existed across Virginia, with greater relative risk found in the central and western parts of the state. We identified significantly elevated relative risk in a number of census tracts. In particular, Henrico, Albemarle, and Botetourt counties all contained at least four census tracts with significantly elevated risk. Conclusions: We identified several areas with significantly elevated ALS risk across Virginia census tracts. These results can inform future studies of potential environmental triggers for the disease, whose etiology is still being understood.

CRISPR/Cas9: implication for modeling and therapy of amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a deadly neurological disease with a complicated and variable pathophysiology yet to be fully understood. There is currently no effective treatment available to either slow or terminate it. However, recent advances in ALS genomics have linked genes to phenotypes, encouraging the creation of novel therapeutic approaches and giving researchers more tools to create efficient animal models. Genetically engineered rodent models replicating ALS disease pathology have a high predictive value for translational research. This review addresses the history of the evolution of gene editing tools, the most recent ALS disease models, and the application of CRISPR/Cas9 against ALS disease.

Gender differences in clinical features at the initial examination of late-onset amyotrophic lateral sclerosis

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that mainly affects motor neurons in the brain and spinal cord. With the advent of aging societies, the proportion of elderly patients with ALS is expected to increase.

METHODS

We retrospectively compared the clinical characteristics at the initial examination of patients with onset of ALS at age 74 years or younger (early onset) and those aged 75 years or older at onset (late-onset) at a single regional ALS diagnostic center in Japan.

RESULTS

The phenotype of late-onset ALS differed between males and females, with late-onset females having more bulbar-onset ALS and significantly lower body mass index, late-onset males having more frequent bulbar and respiratory symptoms at the initial examination, and significantly lower forced vital capacity at the initial examination in both groups compared to early onset patients.

CONCLUSION

For late-onset patients, maintenance of skeletal muscle mass by early intervention for bulbar and respiratory symptoms may be useful for prolonging survival; however, a prospective analysis is warranted.

Characteristic and management motor neuron disease in the largest tertiary hospital in the Philippines: A one-year period cross sectional analytic study

BACKGROUND

Motor neuron disease (MND) is largely understudied in many underdeveloped and developing countries, including the Philippines. The practice and management of MND is generally insufficient, and thus, the quality of life of these patients are consequently compromised.

OBJECTIVES

The aim of this study is to determine the clinical profile and describe the management of MND patients seen in the largest tertiary hospital in the Philippines for one year.

METHODS

This is a cross-sectional study of MND patients diagnosed clinically and via electromyogram-nerve conduction study (EMG NCS) in the Philippine General Hospital (PGH) from January to December 2022. Clinical characteristics, diagnostics and management information were obtained and summarized.

RESULTS

The incidence of MND in our neurophysiology unit was 4.3% (28/648), with amyotrophic lateral sclerosis (ALS) being the most common variant (67.9%, n = 19). Male to Female ratio was 1:1, with the median age of onset of 55 (36-72) years old and median onset duration to diagnosis of 1.5 (0.25-8) years. Limb onset was more prevalent (82.14%, n = 23) with upper limbs initially involved (79.1%, n = 18). Split hand syndrome was found in almost half (53.6%) of the patients. The median ALS functional rating score-revised (ALSFRS-R) and medical research council (MRC) scores were 34 (8-47) and 42(16-60) respectively while the median King's clinical stage was 3 (1-4). Only half of the patients were able to undergo magnetic resonance imaging (MRI) and only one had neuromuscular ultrasound. Only one of the 28 patients was able to take riluzole, and only one was on oxygen support. None had gastrostomy and none used non-invasive ventilation.

CONCLUSION

This study showed that the management of MND in the Philippines is largely inadequate and further improvement in the health care system in handling rare neurologic cases must be implemented to enhance their quality of life.

Amyotrophic lateral sclerosis: a neurodegenerative disorder poised for successful therapeutic translation

Amyotrophic lateral sclerosis (ALS) is a devastating disease caused by degeneration of motor neurons. As with all major neurodegenerative disorders, development of disease-modifying therapies has proven challenging for multiple reasons. Nevertheless, ALS is one of the few neurodegenerative diseases for which disease-modifying therapies are approved. Significant discoveries and advances have been made in ALS preclinical models, genetics, pathology, biomarkers, imaging and clinical readouts over the last 10-15 years. At the same time, novel therapeutic paradigms are being applied in areas of high unmet medical need, including neurodegenerative disorders. These developments have evolved our knowledge base, allowing identification of targeted candidate therapies for ALS with diverse mechanisms of action. In this Review, we discuss how this advanced knowledge, aligned with new approaches, can enable effective translation of therapeutic agents from preclinical studies through to clinical benefit for patients with ALS. We anticipate that this approach in ALS will also positively impact the field of drug discovery for neurodegenerative disorders more broadly.

Methods for informing people with amyotrophic lateral sclerosis/motor neuron disease of their diagnosis

BACKGROUND

Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease (MND), causes increasing physical impairment and disability. People with ALS/MND face huge physical challenges, and the diagnosis can be a source of great psychological distress for both people with ALS/MND and their carers. In such a context, how news of the diagnosis is broken is important. At present, there are no systematic reviews of methods for informing people with ALS/MND of their diagnosis.

OBJECTIVES

To examine the effects and effectiveness of different methods for informing people of a diagnosis of amyotrophic lateral sclerosis/motor neuron disease (ALS/MND), including effects on the person's knowledge and understanding of their disease, its treatment, and care; and on coping and adjustment to the effects of ALS/MND, its treatment, and care.

SEARCH METHODS

We searched the Neuromuscular Specialised Register, CENTRAL, MEDLINE, Embase, PsycINFO, and two trials registers (February 2022). We contacted individuals or organisations to locate studies. We contacted study authors to obtain additional unpublished data.

SELECTION CRITERIA

We planned to include randomised controlled trials (RCTs) and quasi-RCTs of techniques for informing people with ALS/MND of their diagnosis. We planned to include adults (aged 17 years or over) with ALS/MND, according to the El Escorial criteria.

DATA COLLECTION AND ANALYSIS

Three review authors independently reviewed the results of the search to identify RCTs, and three review authors identified non-randomised studies to include in the discussion section. We planned that two review authors would independently extract data, and three would assess the risk of bias in any included trials.

MAIN RESULTS

We did not identify any RCTs that met our inclusion criteria.

AUTHORS' CONCLUSIONS

There are no RCTs that evaluate different communication strategies for breaking the bad news for people diagnosed with ALS/MND. Focused research studies are needed to assess the effectiveness and efficacy of different communication methods.

Early-onset, conjugal, twin-discordant, and clusters of sporadic ALS: Pathway to discovery of etiology via lifetime exposome research

The identity and role of environmental factors in the etiology of sporadic amyotrophic lateral sclerosis (sALS) is poorly understood outside of three former high-incidence foci of Western Pacific ALS and a hotspot of sALS in the French Alps. In both instances, there is a strong association with exposure to DNA-damaging (genotoxic) chemicals years or decades prior to clinical onset of motor neuron disease. In light of this recent understanding, we discuss published geographic clusters of ALS, conjugal cases, single-affected twins, and young-onset cases in relation to their demographic, geographic and environmental associations but also whether, in theory, there was the possibility of exposure to genotoxic chemicals of natural or synthetic origin. Special opportunities to test for such exposures in sALS exist in southeast France, northwest Italy, Finland, the U.S. East North Central States, and in the U.S. Air Force and Space Force. Given the degree and timing of exposure to an environmental trigger of ALS may be related to the age at which the disease is expressed, research should focus on the lifetime exposome (from conception to clinical onset) of young sALS cases. Multidisciplinary research of this type may lead to the identification of ALS causation, mechanism, and primary prevention, as well as to early detection of impending ALS and pre-clinical treatment to slow development of this fatal neurological disease.

Measuring disability in amyotrophic lateral sclerosis/motor neuron disease: the WHODAS 2.0-36, WHODAS 2.0-32, and WHODAS 2.0-12

Aim: To investigate whether the World Health Organization Disability Assessment Schedule 2.0 (WHODAS) can provide interval level measurement of disability in Amyotrophic Lateral Sclerosis (ALS), allowing parametric analyses. Methods: Data on the WHODAS 12, 32, and 36-item versions, from 1120 patients studied at one or more time points, were fit to the Rasch model and comparisons made against ALSFRS-R, King's staging, and mortality. Trajectory modeling was undertaken for a newly diagnosed (≤6 months) cohort of 454 individuals. Results: Total scores for WHODAS 32 and 36-item versions can be converted to interval level measurement suitable for individual clinical use, and the 12-item WHODAS total for group use. The 36-item version is shown to be equivalent to the 32-item version. Expected correlations were seen with King's staging, ALSFRS-R, and EQ-5D-5L. Trajectory analysis of disability (WHODAS 2.0) showed three clearly demarcated groups with differences in King's staging, depressive symptomatology and mortality, but not age. Conclusions: The WHODAS 2.0 is a brief patient reported outcome measure which can be used to measure disability in ALS. Provided the patient answers all 36 (32 if not working) items, the conversion table produces an interval level estimate for parametric analyses. The different trajectories demonstrated from diagnosis support the concept of a prodromal period, and suggest the WHODAS 2.0 could be used for surveillance of at risk populations, such as those with genetic predisposition.

Prevalence of motor neuron diseases in gout patients: a nationwide population-based cohort study

BACKGROUND

Increased uric acid may have a protective effect in motor neuron diseases (MNDs). The association between gout, characterized by hyperuricemia, and MNDs was not investigated previously. To estimate the prevalence of MNDs in gout patients using the Health Insurance and Review Assessment (HIRA) database, a nationwide database of South Korea.

METHODS

The current descriptive study was conducted using the HIRA database. Subjects diagnosed with gout from 2011 to 2018 were included in this study. Among them, the annual prevalence of MNDs was analyzed, stratified by age and sex. Comorbidities including the Charlson Comorbidity Index score and type of prescribed gout-related drug were also demonstrated.

RESULTS

The age-adjusted prevalence of MNDs per 10⁵ persons ranged from 0.598 (95% confidence interval (CI): - 0.231-1.426) to 2.534 (95% CI: 1.100-3.968) between 2011 and 2018. Compared to previous reports, the prevalence of MNDs, especially amyotrophic lateral sclerosis (ALS), in gout patients was significantly lower than in the general population. None of the female gout patients were diagnosed with MNDs. Cerebrovascular accidents, vascular risk factors including hypertension, dyslipidemia, and diabetic complications, and the use of uric acid-lowering agents were more common in gout patients with MNDs than in those without MNDs.

CONCLUSION

This study adds to the evidence of MND prevalence in gout patients. Gout might have a protective effect against the risk of MNDs.

Exosomes-Based Nanomedicine for Neurodegenerative Diseases: Current Insights and Future Challenges

Neurodegenerative diseases constitute a group of pathologies whose etiology remains unknown in many cases, and there are no treatments that stop the progression of such diseases. Moreover, the existence of the blood-brain barrier is an impediment to the penetration of exogenous molecules, including those found in many drugs. Exosomes are extracellular vesicles secreted by a wide variety of cells, and their primary functions include intercellular communication, immune responses, human reproduction, and synaptic plasticity. Due to their natural origin and molecular similarities with most cell types, exosomes have emerged as promising therapeutic tools for numerous diseases. Specifically, neurodegenerative diseases have shown to be a potential target for this nanomedicine strategy due to the difficult access to the brain and the strategy's pathophysiological complexity. In this regard, this review explores the most important biological-origin drug delivery systems, innovative isolation methods of exosomes, their physicochemical characterization, drug loading, cutting-edge functionalization strategies to target them within the brain, the latest research studies in neurodegenerative diseases, and the future challenges of exosomes as nanomedicine-based therapeutic tools.