Association between motor neuron disease and HIV infection: A systematic review of case reports.

BACKGROUND: Motor neuron disease (MND) is a well-known group of neurodegenerative diseases, with amyotrophic lateral sclerosis (ALS) being the most common form. Since 1985, a possible association between MND/ALS and HIV infection has been described. METHODS: We performed a systematic review of case reports and case series involving people living with HIV with MND/ALS through PubMed, Bireme, Embase, and Lilacs databases. The risk of bias was assessed using the Joanna Briggs Institute (JBI) Critical Appraisal Tool for Case Reports. RESULTS: We analyzed 36 articles presenting 88 cases. The mean age was 41.6 years. Antiretroviral therapy (ART) was used by 89.8% and riluzole by 16.9%. First signs and symptoms were similarly present on cervical/upper (25%) and lumbosacral/lower limbs (23.9%), mostly with fasciculations (69.8%) and hyperreflexia (58.8%). MND had a progressive course in 32.9% patients and a clinical improve in 54.6% following ART. The mean survival of the 32 patients who died was 12.3 months and the mean survival of the living patients was 62 months. Respiratory failure was the main cause of death (35.7%). CONCLUSIONS: MND/ALS may present differently in the people living with HIV as a rapidly progressive disease in younger people but with the potential to improve weakness and survival through antiretroviral therapy.

Extracellular vesicles in neurodegenerative, mental, and other neurological disorders: Perspectives into mechanisms, biomarker potential, and therapeutic implications.

Extracellular vesicles (EVs) are produced, secreted, and targeted by most human cells, including cells that compose nervous system tissues. EVs carry several types of biomolecules, such as lipids, proteins and microRNA, and can function as signaling agents in physiological and pathological processes. In this chapter, we will focus on EVs and their cargo secreted by brain cells, especially neurons and glia, and how these aspects are affected in pathological conditions. The chapter covers neurodegenerative disorders, including Alzheimer's disease, Parkinson's disease and amyotrophic lateral sclerosis, as well as several psychiatric disorders, namely schizophrenia, autism spectrum disorder and major depressive disorder. This chapter also addresses other types of neurological dysfunctions, epilepsy and traumatic brain injury. EVs can cross the blood brain barrier, and thus brain EVs may be detected in more accessible peripheral tissue, such as circulating blood. Alterations in EV composition and contents can therefore impart valuable clues into the molecular etiology of these disorders, and serve biomarkers regarding disease prevalence, progression and treatment. EVs can also be used to carry drugs and biomolecules into brain tissue, considered as a promising drug delivery agent for neurological diseases. Therefore, although this area of research is still in its early development, it offers great potential in further elucidating and in treating neurological disorders.

Corrigendum: Neuroprotection by upregulation of the major histocompatibility complex class I (MHC I) in SOD1G93A mice.

[This corrects the article DOI: 10.3389/fncel.2023.1211486.].

TDP-43 nuclear condensation and neurodegenerative proteinopathies.

RNA-binding proteins (RBPs) can undergo phase separation and form condensates, processes that, in turn, can be critical for their functionality. In a recent study, Huang, Ellis, and colleagues show that cellular stress can trigger transient alterations in nuclear TAR DNA-binding protein 43 (TDP-43), leading to changes crucial for proper neuronal function. These findings have implications for understanding neurological TDP-43 proteinopathies.

Profiles of disease progression and predictors of mortality in Colombian patients with amyotrophic lateral sclerosis: a comprehensive longitudinal study.

Objective: This study aimed to assess the prognostic value of the Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) in predicting mortality and characterizing disease progression patterns in ALS patients in Colombia. Methods: We conducted a retrospective longitudinal analysis of 537 ALS patients from the Roosevelt Institute Rehabilitation Service between October 2008 and October 2022. The study excluded nine patients due to incomplete data, resulting in 528 individuals in the analysis. ALS diagnoses were confirmed using the revised El Escorial and Gold Coast criteria. Disease progression was assessed using the ALSFRS-R, and mortality data were sourced from follow-up calls and a national database. Statistical analysis included Cox proportional hazards models to identify mortality predictors and Growth Mixture Modeling (GMM) to explore ALS progression trajectories. Results: The majority of the cohort (63.8%) deceased within the 84-month follow-up period. Survival analysis revealed that each point increase in the ALSFRS-R rate was associated with a 2.22-fold (95% CI =1.99-2.48, p < 0.001) increased risk of mortality. In the population with data from two clinical visits, the ALSFRS-R rate based on initial assessments predicted mortality more effectively over 36 months than the rate based on two evaluations. GMM identified three distinct progression trajectories: slow, intermediate, and rapid decliners. Conclusions: The ALSFRS-R rate, derived from self-reported symptom onset, significantly predicts mortality, underscoring its value in clinical assessments. This study highlights the heterogeneity in disease progression among Colombian ALS patients, indicating the necessity for personalized treatment approaches based on individual progression trajectories. Further studies are needed to refine these predictive models and improve patient management and outcomes.

Proteomic analysis of cerebrospinal fluid of amyotrophic lateral sclerosis patients in the presence of autologous bone marrow derived mesenchymal stem cells.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a fatal and rapidly progressive motoneuron degenerative disorder. There are still no drugs capable of slowing disease evolution or improving life quality of ALS patients. Thus, autologous stem cell therapy has emerged as an alternative treatment regime to be investigated in clinical ALS. METHOD: Using Proteomics and Protein-Protein Interaction Network analyses combined with bioinformatics, the possible cellular mechanisms and molecular targets related to mesenchymal stem cells (MSCs, 1 × 106 cells/kg, intrathecally in the lumbar region of the spine) were investigated in cerebrospinal fluid (CSF) of ALS patients who received intrathecal infusions of autologous bone marrow-derived MSCs thirty days after cell therapy. Data are available via ProteomeXchange with identifier PXD053129. RESULTS: Proteomics revealed 220 deregulated proteins in CSF of ALS subjects treated with MSCs compared to CSF collected from the same patients prior to MSCs infusion. Bioinformatics enriched analyses highlighted events of Extracellular matrix and Cell adhesion molecules as well as related key targets APOA1, APOE, APP, C4A, C5, FGA, FGB, FGG and PLG in the CSF of cell treated ALS subjects. CONCLUSIONS: Extracellular matrix and cell adhesion molecules as well as their related highlighted components have emerged as key targets of autologous MSCs in CSF of ALS patients. TRIAL REGISTRATION: Clinicaltrial.gov identifier NCT0291768. Registered 28 September 2016.

Mitochondrial genome variants associated with amyotrophic lateral sclerosis and their haplogroup distribution.

INTRODUCTION/AIMS: Amyotrophic lateral sclerosis (ALS) may be familial or sporadic, and twin studies have revealed that even sporadic forms have a significant genetic component. Variants in 55 nuclear genes have been associated with ALS and although mitochondrial dysfunction is observed in ALS, variants in mitochondrial genomes (mitogenomes) have not yet been tested for association with ALS. The aim of this study was to determine whether mitogenome variants are associated with ALS. METHODS: We conducted a genome-wide association study (GWAS) in mitogenomes of 1965 ALS patients and 2547 controls. RESULTS: We identified 51 mitogenome variants with p values <10-7, of which 13 had odds ratios (ORs) >1, in genes RNR1, ND1, CO1, CO3, ND5, ND6, and CYB, while 38 variants had OR <1 in genes RNR1, RNA2, ND1, ND2, CO2, ATP8, ATP6, CO3, ND3, ND4, ND5, ND6, and CYB. The frequencies of haplogroups H, U, and L, the most frequent in our ALS data set, were the same in different onset sites (bulbar, limb, spinal, and axial). Also, intra-haplogroup GWAS revealed unique ALS-associated variants in haplogroups L and U. DISCUSSION: Our study shows that mitogenome single nucleotide variants (SNVs) are associated with ALS and suggests that these SNVs could be included in routine genetic testing for ALS and that mitochondrial replacement therapy has the potential to serve as a basis for ALS treatment.

Amyotrophic Lateral Sclerosis (ALS): An Overview of Genetic and Metabolic Signaling Mechanisms.

Amyotrophic Lateral Sclerosis (ALS) is a rare, progressive, and incurable disease. Sporadic (sALS) accounts for ninety percent of ALS cases, while familial ALS (fALS) accounts for around fifteen percent. Reports have identified over 30 different forms of familial ALS. Multiple types of fALS exhibit comparable symptoms with mutations in different genes and possibly with different predominant metabolic signals. Clinical diagnosis takes into account patient history but not genetic mutations, misfolded proteins, or metabolic signaling. As research on genetics and metabolic pathways advances, it is expected that the intricate complexity of ALS will compound further. Clinicians discuss whether a gene's presence is a cause of the disease or just an association or consequence. They believe that a mutant gene alone is insufficient to diagnose ALS. ALS, often perceived as a single disease, appears to be a complex collection of diseases with similar symptoms. This review highlights gene mutations, metabolic pathways, and muscle-neuron interactions.

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.

Trehalose Protects against Superoxide Dismutase 1 Proteinopathy in an Amyotrophic Lateral Sclerosis Model.

This work aimed to study the effect of trehalose in protecting cells against Sod1 proteinopathy associated with amyotrophic lateral sclerosis (ALS). Humanized yeast cells in which native Sod1 was replaced by wild-type human Sod1 or an ALS mutant (WT-A4V Sod1 heterodimer) were used as the experimental model. Cells were treated with 10% trehalose (p/v) before or after the appearance of hSod1 proteinopathy induced by oxidative stress. In both conditions, trehalose reduced the number of cells with Sod1 inclusions, increased Sod1 activity, and decreased the levels of intracellular oxidation, demonstrating that trehalose avoids Sod1 misfolding and loss of function in response to oxidative stress. The survival rates of ALS Sod1 cells stressed in the presence of trehalose were 60% higher than in their absence. Treatment with trehalose after the appearance of Sod1 inclusions in cells expressing WT Sod1 doubled longevity; after 5 days, non-treated cells did not survive, but 15% of cells treated with sugar were still alive. Altogether, our results emphasize the potential of trehalose as a novel therapy, which might be applied preventively in ALS patients with a family history of the disease or after diagnosis in ALS patients who discover the disease following the first symptoms.

Tongue pressure is a strong predictor of recommendation for gastrostomy in amyotrophic lateral sclerosis.

INTRODUCTION/AIMS: Objective and practical biomarkers to determine the need for gastrostomy in patients with amyotrophic lateral sclerosis (ALS) are lacking. Tongue pressure (TP) is a promising biomarker because it is associated with bulbar dysfunction. The aims of this study were to evaluate the association of TP with the need for gastrostomy, and to determine its optimal cut-off value. METHODS: This prospective observational study included participants with ALS taking nutrition orally. TP was evaluated using the Iowa Oral Performance Instrument. Need for gastrostomy as determined by a multidisciplinary team during a 12-month follow up period was recorded. Associations between TP and need for gastrostomy placement were performed. ROC curve analysis determined the optimal cut-off value of TP to predict gastrostomy. RESULTS: Of 208 screened participants, 119 were included. Gastrostomy was indicated in 45% (53), in a 12-month follow up period. TP of ≤20 kPA was a strong predictor of gastrostomy indication (OR 11.8, CI 95% [4.61, 34.7], p < .001). The association persisted even after adjustment for weight loss, pneumonia, prolonged feeding duration, Revised ALS Functional Rating Scale score, and American Speech-Language-Hearing Association scale score (OR 4.51, CI 95% [1.50, 14.9], p = .009). By receiver operating characteristic curve analysis, 20 kPA represented the optimal cut-off value (sensitivity 0.75, specificity 0.89). DISCUSSION: TP is a strong independent predictor of gastrostomy indication in the subsequent 12 months in patients with ALS, with good sensitivity and specificity at a cutoff value of ≤20 kPA, suggesting that it may be a promising biomarker in clinical practice.

The connection between gut microbiota and its metabolites with neurodegenerative diseases in humans.

The aging of populations is a global phenomenon that follows a possible increase in the incidence of neurodegenerative diseases. Alzheimer's, Parkinson's, Multiple Sclerosis, Amyotrophic Lateral Sclerosis, and Huntington's diseases are some neurodegenerative disorders that aging could initiate or aggravate. Recent research has indicated that intestinal microbiota dysbiosis can trigger metabolism and brain functioning, contributing to the etiopathogenesis of those neurodegenerative diseases. The intestinal microbiota and its metabolites show significant functions in various aspects, such as the immune system modulation (development and maturation), the maintenance of the intestinal barrier integrity, the modulation of neuromuscular functions in the intestine, and the facilitation of essential metabolic processes for both the microbiota and humans. The primary evidence supporting the connection between intestinal microbiota and its metabolites with neurodegenerative diseases are epidemiological observations and animal models experimentation. This paper reviews up-to-date evidence on the correlation between the microbiota-gut-brain axis and neurodegenerative diseases, with a specially focus on gut metabolites. Dysbiosis can increase inflammatory cytokines and bacterial metabolites, altering intestinal and blood-brain barrier permeability and causing neuroinflammation, thus facilitating the pathogenesis of neurodegenerative diseases. Clinical data supporting this evidence still needs to be improved. Most of the works found are descriptive and associated with the presence of phyla or species of bacteria with neurodegenerative diseases. Despite the limitations of recent research, the potential for elucidating clinical questions that have thus far eluded clarification within prevailing pathophysiological frameworks of health and disease is promising through investigation of the interplay between the host and microbiota.

Consideraciones bioéticas en el manejo de la esclerosis lateral amiotrófica: Una aproximación al quehacer fonoaudiológico

Introducción: La esclerosis lateral amiotrófica (ELA) es la forma más común de enfermedad degenerativa de motoneurona en la edad adulta y es considerada una enfermedad terminal. Por lo mismo, el accionar del fonoaudiólogo debe considerar el respeto a los principios bioéticos básicos para garantizar una asistencia adecuada. Objetivo: Conocer aquellas consideraciones bioéticas relacionadas al manejo y estudio de personas con ELA para luego brindar una aproximación hacia el quehacer fonoaudiológico. Método: Se efectuó una búsqueda bibliográfica en las bases de datos PubMed, Scopus y SciELO. Se filtraron artículos publicados desde 2000 hasta junio de 2023 y fueron seleccionados aquellos que abordaban algún componente bioético en población con ELA. Resultados: Aspectos relacionados al uso del consentimiento informado y a la toma de decisiones compartidas destacaron como elementos esenciales para apoyar la autonomía de las personas. Conclusión: Una correcta comunicación y una toma de decisiones compartida son claves para respetar la autonomía de las personas. A su vez, la estandarización de procedimientos mediante la investigación clínica permitirá aportar al cumplimiento de los principios bioéticos de beneficencia y no maleficencia, indispensables para la práctica profesional.

Introduction: Amyotrophic lateral sclerosis (ALS) is the most common form of degenerative motor neuron disease in adulthood and is considered a terminal disease. For this reason, the actions of the speech therapist must consider respect for basic bioethical principles to guarantee adequate assistance. Objective: To know those bioethical considerations related to the management and study of people with ALS to then provide an approach to speech therapy. Methodology: A bibliographic search was carried out in the PubMed, Scopus, and SciELO databases. Articles published from 2000 to June 2023 were filtered and those that addressed a bioethical component in the population with ALS were selected. Results: Aspects related to the use of informed consent and shared decision-making stood out as essential elements to support people's autonomy. Conclusion: Proper communication and shared decision-making are key to respecting people's autonomy. In turn, the standardization of procedures through clinical research will contribute to compliance with the bioethical principles of beneficence and non-maleficence, essential for professional practice.

A homozygous p.Val120Leu (c.358G > C) SOD1 mutation led to slowly progressive amyotrophic lateral sclerosis in a Brazilian family.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease usually associated with severe weakness and death within 2-5 years. SOD1 mutations cause hereditary ALS in autosomal dominant and rarely in recessive pattern. We describe a new phenotype of slowly progressive fALS due to homozygous SOD1 mutations (c.358G > C, p.Val120Leu) in a Brazilian family. We reviewed the medical chart and interviewed the index patient and other relatives. A 41-year-old man developed weakness in his legs, leading to frequent falls, followed over the next few months with progressive arm fasciculations and muscle atrophy. The SOD1 enzymatic activity in erythrocytes was slightly decreased. A genetic test panel disclosed homozygous SOD1 mutations (c.358G > C, p.Val120Leu). His asymptomatic parents also carried one mutant allele and 2 brothers and a sister had died with ALS. We reported a new family with homozygous SOD1 mutation and slowly progressive ALS course. Further studies are necessary to confirm whether this mutation can also lead to disease in heterozygosis with incomplete penetrance.

The familial amyotrophic lateral sclerosis-associated A4V SOD1 mutant is not able to regulate aerobic glycolysis.

Under certain stress conditions, astrocytes operate in aerobic glycolysis, a process controlled by pyruvate dehydrogenase (PDH) inhibition through its E1 α subunit (Pda1) phosphorylation. This supplies lactate to neurons, which save glucose to obtain NADPH to, among other roles, counteract reactive oxygen species. A failure in this metabolic cooperation causes severe damage to neurons. In this work, using humanized Saccharomyces cerevisiae cells in which its endogenous Cu/Zn Superoxide Dismutase (SOD1) was replaced by human ortholog, we investigated the role of human SOD1 (hSOD1) in aerobic glycolysis regulation and its implications to amyotrophic lateral sclerosis (ALS), a neurodegenerative disease. Yeast cells ferment glucose even in the presence of oxygen and switch to respiratory metabolism after glucose exhaustion. However, like cells of SOD1-knockout strain, cells expressing A4V mutant of hSOD1 growing on glucose showed a respiratory phenotype, i.e., low glucose and high oxygen consumptions and low intracellular oxidation levels in response to peroxide stress, contrary to cells expressing wild-type (WT) SOD1 (yeast or human). The A4V mutation in hSOD1 is linked to ALS. In contrast to WT SOD1 strains, PDH activity of both sod1Δ and A4V hSOD1 cells did not change in response to a metabolic shift toward oxidative metabolism, which was associated to lower Pda1 phosphorylation levels under growth on glucose. Taken together, our results suggest that A4V mutant cannot regulate aerobic glycolysis via Pda1 phosphorylation the same way WT hSOD1, which might be linked to problems observed in the motor neurons of ALS patients with the SOD1 A4V mutation.

Language impairment in sporadic and familial (type 8) amyotrophic lateral sclerosis: A comparative study.

INTRODUCTION/AIMS: Language is frequently affected in patients with sporadic amyotrophic lateral sclerosis (sALS), with reduced performance in naming, syntactic comprehension, grammatical expression, and orthographic processing. However, the language profile of patients with familial type 8 ALS (ALS8), linked to p.P56S VAPB mutation, remains unclear. We investigated language in patients with ALS8 by examining their auditory comprehension and verbal production. METHODS: We included three groups of participants: (1) patients with sALS (n = 20), (2) patients with familial ALS8 (n = 22), and (3) healthy controls (n = 21). The groups were matched for age, sex, and education level. All participants underwent a comprehensive language battery, including the Boston Diagnostic Aphasia Examination, the reduced Token test, letter fluency, categorical fluency (animals), word definition from the Cambridge Semantic Memory Research Battery, and a narrative discourse analysis. Participants also were evaluated using Addenbrooke's Cognitive Exam-Revised Version, the Hospital Anxiety and Depression Scale, and the ALS Functional Rating Scale-Revised. RESULTS: Compared to controls, sALS and ALS8 patients had impaired performance on oral (syntactic and phonological processing) comprehension and inappropriate discourse cohesion. sALS and ALS8 did not differ in any language measure. There was no correlation between language scores and functional and psychiatric scales. DISCUSSION: ALS8 patients exhibit language deficits that are independent of motor features. These findings are consistent with the current evidence suggesting that ALS8 has prominent non-motor features.

Knockdown of tgfb1a partially improves ALS phenotype in a transient zebrafish model.

Amyotrophic lateral sclerosis (ALS) corresponds to a neurodegenerative disorder marked by the progressive degeneration of both upper and lower motor neurons located in the brain, brainstem, and spinal cord. ALS can be broadly categorized into two main types: sporadic ALS (sALS), which constitutes approximately 90% of all cases, and familial ALS (fALS), which represents the remaining 10% of cases. Transforming growth factor type-ß (TGF-ß) is a cytokine involved in various cellular processes and pathological contexts, including inflammation and fibrosis. Elevated levels of TGF-ß have been observed in the plasma and cerebrospinal fluid (CSF) of both ALS patients and mouse models. In this perspective, we explore the impact of the TGF-ß signaling pathway using a transient zebrafish model for ALS. Our findings reveal that the knockdown of tgfb1a lead to a partial prevention of motor axon abnormalities and locomotor deficits in a transient ALS zebrafish model at 48 h post-fertilization (hpf). In this context, we delve into the proposed distinct roles of TGF-ß in the progression of ALS. Indeed, some evidence suggests a dual role for TGF-ß in ALS progression. Initially, it seems to exert a neuroprotective effect in the early stages, but paradoxically, it may contribute to disease progression in later stages. Consequently, we suggest that the TGF-ß signaling pathway emerges as an attractive therapeutic target for treating ALS. Nevertheless, further research is crucial to comprehensively understand the nuanced role of TGF-ß in the pathological context.

Exploring antioxidant strategies in the pathogenesis of ALS.

The central nervous system is essential for maintaining homeostasis and controlling the body's physiological functions. However, its biochemical characteristics make it highly vulnerable to oxidative damage, which is a common factor in neurodegenerative diseases like amyotrophic lateral sclerosis (ALS). ALS is a leading cause of motor neuron disease, characterized by a rapidly progressing and incurable condition. ALS often results in death from respiratory failure within 3-5 years from the onset of the first symptoms, underscoring the urgent need to address this medical challenge. The aim of this study is to present available data supporting the role of oxidative stress in the mechanisms underlying ALS and to discuss potential antioxidant therapies currently in development. These therapies aim to improve the quality of life and life expectancy for patients affected by this devastating disease.

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.