Cognitive-behavioral longitudinal assessment in ALS: the Italian Edinburgh Cognitive and Behavioral ALS screen (ECAS)

High Frequency of Cognitive and Behavioral Impairment in Amyotrophic Lateral Sclerosis Patients with SOD1 Pathogenic Variants

OBJECTIVE

While the cognitive-behavioral characteristics of amyotrophic lateral sclerosis (ALS) patients carrying C9orf72 pathological repeat expansion have been extensively studied, our understanding of those carrying SOD1 variants is mostly based on case reports. The aim of this paper is to extensively explore the cognitive-behavioral characteristics of a cohort of ALS patients carrying pathogenetic variants of SOD1 gene, comparing them to patients without pathogenetic variants of 46 ALS-related genes (wild-type [WT]-ALS) and healthy controls.

METHODS

All ALS patients seen at the Turin ALS expert center in the 2009-2021 period who underwent both cognitive/behavioral and extensive genetic testing were eligible to be included in the study. Only patients with SOD1 pathogenetic variants (n = 28) (SOD1-ALS) and WT-ALS (n = 829) were enrolled in the study. A series of 129 controls was also included.

RESULTS

Among the 28 SOD1-ALS patients, 16 (57.1%) had normal cognitive function, 5 (17.9%) isolated cognitive impairment (ALSci) (17.9%), 6 (21.4%) isolated behavioral impairment (ALSbi), 1 (3.6%) cognitive and behavioral impairment (ALScbi), and no one ALS-FTD. SOD1-ALS performed worse than controls in all explored domains, in particular Social Cognition and Language domains. SOD1-ALS patients had similar scores in all tests compared to WT-ALS, except the Story-based Empathy Task (SET), where they performed worse.

INTERPRETATION

Cognitive-behavioral impairment is much more common in SOD1 patients than previously assumed. SOD1-ALS are characterized by a more frequent impairment of Social Cognition and, less markedly, of Language domains. These findings have relevant implication both in the clinical and in the research setting, also considering recently approved treatment for SOD1-ALS. ANN NEUROL 2024;96:150-158.

Loneliness as neurobehavioral issue in amyotrophic lateral sclerosis

OBJECTIVE

In elderly people loneliness represents a risk factor for dementia and may negatively impact on mental and physical health. The specific contribute of loneliness to cognitive and behavioral functioning have not yet been determined in amyotrophic lateral sclerosis (ALS). Our hypothesis was that loneliness may be related to motor dysfunction with a negative impact on cognitive and behavioral decline, possibly related to specific cortical involvement.

METHODS

In 200 ALS patients (ALSpts) and 50 healthy controls (HCs) we measured loneliness, mood, and quality of life (QoL). ALSpts underwent comprehensive clinical, genetic, and neuropsychological assessment to define phenotypes. Seventy-seven ALSpts performed 3T MRI scans to measure cortical thickness. Between-group, partial correlation and regression analyses were used to examined clinical, neuropsychological, and cortical signatures of loneliness.

RESULTS

Feelings of loneliness were documented in 38% of ALSpts (ALS/L+pts) and in 47% of HCs. In both groups loneliness was associated with anxiety (P < 0.001), depression (P ≤ 0.005), and poor QoL (P < 0.001). ALS/L+pts had similar motor dysfunctions and cognitive abilities than non-lonely ALSpts, but distinct behavioral profiles (P ≤ 0.005) and frontoparietal involvement (P < 0.05). Loneliness in ALS is related to behavioral changes, apathy, and emotional dysregulation (P < 0.001).

INTERPRETATION

Our cross-sectional study indicates that, in ALS, the satisfaction of social environment is associated with a sense of life well-being that is not limited to the motor status, proving instead that loneliness can impact on disease-related neurobehavioral changes with a possible flashback on brain architecture. This suggests that sociality could promote personal resilience against behavioral and affective decline in ALS.

Longitudinal Feasibility of the Montreal Cognitive Assessment (MoCA) in Non-Demented ALS Patients

INTRODUCTION

The present study aimed at testing the longitudinal feasibility of the Montreal Cognitive Assessment (MoCA) in an Italian cohort of non-demented amyotrophic lateral sclerosis (ALS) patients.

METHODS

N = 39 non-demented ALS patients were followed-up at a 5-to-10-month interval (M = 6.8; SD = 1.4) with the MoCA and the Edinburgh Cognitive and Behavioral ALS Screen (ECAS). Practice effects, test-retest reliability, and predictive validity (against follow-up ECAS scores) were assessed. Reliable change indices (RCIs) were derived via a regression-based approach by accounting for retest interval and baseline confounders (i.e., demographics, disease duration, and severity and progression rate).

RESULTS

At retest, 100% and 69.2% of patients completed the ECAS and the MoCA, respectively. Patients who could not complete the MoCA showed a slightly more severe and fast-progressing disease. The MoCA was not subject to practice effects (t[32] = -0.80; p = 0.429) and was reliable at retest (intra-class correlation = 0.82). Moreover, baseline MoCA scores predicted the ECAS at retest. RCIs were successfully derived - with baseline MoCA scores being the only significant predictor of retest performances (ps < 0.001).

CONCLUSIONS

As long as motor disabilities do not undermine its applicability, the MoCA appears to be longitudinally feasible at a 5-to-10-month interval in non-demented ALS patients. However, ALS-specific screeners - such as the ECAS - should be preferred whenever possible.

Frontotemporal-spectrum disorders and functional independence in non-demented ALS patients

BACKGROUND

The present study aimed at determining whether, net of motor confounders, neuropsychological features affect functional independence (FI) in activities of daily living (ADLs) in non-demented amyotrophic lateral sclerosis (ALS) patients.

METHODS

N = 88 ALS patients without frontotemporal dementia were assessed for FI-Katz's Basic ADL Scale (BADL) and Lawton-Brody's Instrumental ADL Scale (IADL)-, cognition-Edinburgh Cognitive and Behavioural ALS Screen (ECAS)-and behaviour-Beaumont Behavioural Inventory and Dimensional Apathy Scale. The association between cognitive and behavioural measures and BADL/IADL scores was assessed by covarying for demographics, anxiety and depression levels, disease duration and motor confounders-i.e. ALS Functional Rating Scale-Revised (ALSFRS-R) scores, progression rate and both King's and Milano-Torino stages.

RESULTS

Higher scores on the ECAS-Language were associated with higher IADL scores (p = 0.005), whilst higher apathetic features-as measured by the Dimensional Apathy Scale (DAS)-were inversely related to the BADL (p = 0.003). Whilst IADL scores were related to all ECAS-Language tasks, the DAS-Initiation was the only subscale associated with BADL scores. Patients with abnormal ECAS-Language (p = 0.023) and DAS (p = 0.008) scores were more functionally dependent than those without.

DISCUSSION

Among non-motor features, language changes and apathetic features detrimentally affect FI in non-demented ALS patients.

Clinical usability of the Story-Based Empathy Task (SET) in non-demented ALS patients

BACKGROUND

This study aimed at assessing the clinical usability of the Story-Based Empathy Task (SET) in non-demented amyotrophic lateral sclerosis (ALS) patients.

METHODS

N = 106 non-demented ALS patients and N = 101 healthy controls (HCs) were administered the SET, which includes three subtests assessing Emotion Attribution (SET-EA), Intention Attribution (SET-IA) and causal inference (SET-CI) - the latter being a control task. Patients also underwent the Reading the Mind in the Eyes Test (RMET), the Edinburgh Cognitive and Behavioural ALS Screen (ECAS) and a thorough behavioural and motor-functional evaluation. The diagnostics of the SET-EA and -IA were tested against a defective performance on the RMET. The association between SET subtests and cognitive/behavioural outcomes was examined net of demographic and motor-functional confounders. Case-control discrimination was explored for each SET subtest.

RESULTS

Demographically adjusted SET-EA and -IA scores accurately detected defective RMET performances at the optimal cutoffs of <3.04 (AUC = .84) and <3.61 (AUC = .88), respectively. By contrast, the SET-CI performed poorly in doing so (AUC = .58). The SET-EA converged with the RMET, as well as with ECAS-Executive and -Memory scores, whilst the SET-IA was unrelated to cognitive measures (including the RMET); the SET-CI was related to the ECAS-Language the ECAS-Executive. SET subscores were unrelated to behavioural outcomes. Only the SET-EA discriminated patients from HCs.

CONCLUSIONS

The SET as a whole should not be addressed as a social-cognitive measure in this population. At variance, its subtest tapping on emotional processing - i.e., the SET-EA - is recommended for use as an estimate of social-cognitive abilities in non-demented ALS patients.

Italian reference values and brain correlates of verbal fluency index - vs standard verbal fluency test - to assess executive dysfunction in ALS

Objectives: In amyotrophic lateral sclerosis (ALS), verbal fluency index (Vfi) is used to investigate fluency accounting for motor impairment. This study has three aims: (1) to provide Vfi reference values from a cohort of Italian healthy subjects; (2) to assess the ability of Vfi reference values (vs standard verbal fluency test [VFT]) in distinguishing ALS patients with and without executive dysfunction; and (3) to investigate the association between Vfi and brain structural features of ALS patients. Methods: We included 180 healthy subjects and 157 ALS patients who underwent neuropsychological assessment, including VFT and Vfi, and brain MRI. Healthy subjects were split into four subgroups according to sex and education. For each subgroup, we defined the 95th percentile of Vfi as the cutoff. In ALS, the distributions of "abnormal" cases based on Vfi and standard VFT cutoffs were compared using Fisher's exact test. Using quantile regressions in patients, we assessed the association between Vfi and VFT scores, separately, with gray matter volumes and white matter (WM) tract integrity. Results: Applying Vfi and VFT cutoffs, 9 and 13% of ALS cases, respectively, had abnormal scores (p < 0.001). In ALS, while higher Vfi scores were associated with WM changes of callosal fibers linking supplementary motor area, lower VFT performances related to corticospinal tract alterations. Discussion: We provided Italian reference values for the spoken Vfi. Compared to VFT, Vfis are critical to disentangle motor and cognitive deficits in ALS. In patients, abnormal Vfis were associated with damage to WM tracts specifically involved in ideational information processing.

Bulbar involvement and cognitive features in amyotrophic lateral sclerosis: a retrospective study on 347 patients

Background

This study aimed at clarifying the role of bulbar involvement (BI) as a risk factor for cognitive impairment (CI) in non-demented amyotrophic lateral sclerosis (ALS) patients.

Methods

Data on N = 347 patients were retrospectively collected. Cognition was assessed via the Edinburgh Cognitive and Behavioral ALS Screen (ECAS). On the basis of clinical records and ALS Functional Rating Scale-Revised (ALSFRS-R) scores, BI was characterized as follows: (1) BI at onset-from medical history; (2) BI at testing (an ALSFRS-R-Bulbar score ≤11); (3) dysarthria (a score ≤3 on item 1 of the ALSFRS-R); (4) severity of BI (the total score on the ALSFRS-R-Bulbar); and (5) progression rate of BI (computed as 12-ALSFRS-R-Bulbar/disease duration in months). Logistic regressions were run to predict a below- vs. above-cutoff performance on each ECAS measure based on BI-related features while accounting for sex, disease duration, severity and progression rate of respiratory and spinal involvement and ECAS response modality.

Results

No predictors yielded significance either on the ECAS-Total and -ALS-non-specific or on ECAS-Language/-Fluency or -Visuospatial subscales. BI at testing predicted a higher probability of an abnormal performance on the ECAS-ALS-specific (p = 0.035) and ECAS-Executive Functioning (p = 0.018). Lower ALSFRS-R-Bulbar scores were associated with a defective performance on the ECAS-Memory (p = 0.025). No other BI-related features affected other ECAS performances.

Discussion

In ALS, the occurrence of BI itself, while neither its specific features nor its presence at onset, might selectively represent a risk factor for executive impairment, whilst its severity might be associated with memory deficits.

Equating norms between the ALS Cognitive Behavioral Screen (ALS-CBS™) and the Edinburgh Cognitive and Behavioural ALS Screen (ECAS) in non-demented ALS patients

BACKGROUND

The present study aimed at deriving equating norms to estimate scores on the Edinburgh Cognitive and Behavioural ALS Screen (ECAS) based on those on the ALS Cognitive Behavioral Screen (ALS-CBS™) in an Italian cohort of non-demented ALS patients.

METHODS

ALS-CBS™ and ECAS scores of 293 ALS patients without frontotemporal dementia were retrospectively retrieved. Concurrent validity of the ALS-CBS™ towards the ECAS was tested by covarying for demographics, disease duration and severity, presence of C9orf72 hexanucleotide repeat expansion and behavioural features. A linear-smoothing equipercentile equating (LSEE) model was employed to derive ALS-CBS™-to-ECAS cross-walks. Gaps in LSEE-based estimation were managed via a linear regression-based equating approach. Equivalence between empirical and derived ECAS scores was tested via a two-one-sided test (TOST) procedure for the dependent sample.

RESULTS

The ALS-CBS™ predicted the ECAS (β = 0.75), accounting for the vast majority of its variance (60% out of an R² = 0.71). Consistently, a strong, one-to-one linear association between ALS-CBS™ and ECAS scores was detected (r = 0.84; R² = 0.73). The LSEE was able to estimate conversions for the full range of the ALS-CBS™, except for raw scores equal to 1 and 6 - for whom a linear equating-based equation was derived. Empirical ECAS scores were equivalent to those derived with both methods.

DISCUSSION

Italian practitioners and researchers have been herewith provided with valid, straightforward cross-walks to estimate the ECAS based on ALS-CBS™ scores in non-demented ALS patients. Conversions herewith provided will help avoid cross-sectional/longitudinal inconsistencies in test adoption within research, and possibly clinical, settings.

Clinimetrics of the cognitive section of the Italian ALS Cognitive Behavioral Screen (ALS-CBS™)

BACKGROUND

The present study aimed at (1) providing further validity and reliability evidence for the Italian version of the cognitive section of the ALS Cognitive Behavioral Screen (ALS-CBS™) and (2) testing its diagnostics within an Italian ALS cohort, as well as at (3) exploring its capability to discriminate patients from healthy controls (HCs).

METHODS

N = 293 non-demented ALS patients were administered the cognitive sections of the ALS-CBS™ and Edinburgh Cognitive and Behavioural ALS Screen (ECAS). N = 96 HCs demographically matched with N = 96 patients were also administered the cognitive section of the ALS-CBS™. In patients, factorial and construct validity, internal reliability, and diagnostics against a defective score on the cognitive section of the ECAS were tested. Case-control discrimination was assessed via a logistic regression.

RESULTS

ALS-CBS™ cognitive subscales were underpinned by a simple, unidimensional structure, internally reliable (McDonald's ω = 0.74), and mostly related with ECAS executive and fluency scores (r_s = 0.54-0.71). Both raw and age- and education-adjusted scores on the cognitive section of the ALS-CBS™ accurately detected ECAS-defined cognitive impairment (AUC = 0.80 and .88, respectively), yielding optimal error-based, information-based and unitary diagnostics. A cut-off of < 15.374 was identified on adjusted scores. The test was able to discriminate patients from HCs (p < 0.001).

DISCUSSION

The cognitive section of the Italian ALS-CBS™ is a valid, reliable, and diagnostically sound ALS-specific screener for detecting frontotemporal, executive-/attentive-based cognitive inefficiency in non-demented ALS patients, being also able to discriminate them from normotypical individuals.

Diagnostic properties of the Italian ECAS Carer Interview (ECAS-CI)

BACKGROUND

This study aimed at providing diagnostic properties and normative cut-offs for the Italian ECAS Carer Interview (ECAS-CI).

MATERIALS

N = 292 non-demented ALS patients and N = 107 healthy controls (HCs) underwent the ECAS-CI and the Frontal Behavioural Inventory (FBI). Two ECAS-CI measures were addressed: (1) the number of symptoms (NoS; range = 0-13) and (2) that of individual symptom clusters (SC; range = 0-6). Diagnostics were explored against an FBI score ≥ than the 95th percentile of the patients' distribution.

RESULTS

Both the NoS and SC discriminated patient from HCs. High accuracy, sensitivity, and specificity were detected for both the NoS and SC; however, at variance with SC, the NoS showed better post-test features and did not overestimate the occurrence of behavioural changes. The ECAS-CI converged with the FBI and diverged from the cognitive section of the ECAS.

DISCUSSION

The ECAS-CI is a suitable screener for behavioural changes in ALS patients, with the NoS being its best outcome measure (cut-off: ≥ 3).

Cognition in the course of ALS-a meta-analysis

Objective: The goal of this meta-analysis is to improve insight into the development of cognition over the course of ALS and to assess predictors of cognitive performance.Method: A literature search was conducted in Pubmed and Web of Science on 29 July 2019 and 16 March 2021. Data were screened in Endnote^® Version X9 (London, UK). Meta-analyses and meta-regressions were calculated for cross-sectional data using Rstudio^®. Studies were assigned to temporal and physical categories and Hedges' g was calculated for the respective categories to provide an estimate of a cognitive course based on cross-sectional data. Due to low numbers and heterogeneity in reporting, longitudinal studies were analyzed descriptively.Results: A total of N = 45 cross-sectional and N = 13 longitudinal studies were included. Impairments in all cognitive domains, except verbal IQ, were found in ALS patients (PALS). PALS showed stable cognitive performances in cross-sectional and in most longitudinal studies. PALS with symptoms for 18-24 months and PALS who had an ALSFRS-R score of 40-36 were the most frequently reported subgroup regarding neuropsychology. Age was related to visuospatial functioning, and depressiveness to attention. In longitudinal studies, impact of site of onset and cognitive status at baseline on cognitive course was found.Conclusion: Despite vast evidence for cognitive impairment at disease onset in different domains, evidence for evolution of these deficits is rather limited, suggesting that PALS present with cognitive impairment early in the course possibly in a sense of disease trait.

Apathy in amyotrophic lateral sclerosis: systematic review and meta-analysis of frequency, correlates, and outcomes

Objectives: To determine the frequency and correlates of apathy in amyotrophic lateral sclerosis (ALS) and its influence on the prognosis of the disease.Methods: Three databases were searched: MEDLINE, PubMed, and Google Scholar. Quantitative synthesis of the frequency of apathy in ALS was conducted using random effects in Stata (College Station, TX). Meta-regression and subgroup analyses were conducted to investigate the association between frequency of apathy in ALS and different covariates.Results: Fifty-two studies (51 cohorts) were included in the analysis. The pooled frequency of apathy in ALS was 25% (95% confidence interval (CI) 14-35%) according to the studies that used self-rated tools and 34% (95% CI 27-41%) according to studies that used informant-rated tools. The emergence of apathy was associated with cognitive decline and bulbar onset of the disease. There was no consistent relationship between apathy and disease stage or the severity of depression. Structural brain imaging studies established that ALS patients with apathy exhibited more prominent changes with structural and functional brain imaging particularly involving fronto-subcortical regions of the brain. Overall, apathy worsened the long-term prognosis of ALS.Discussion: Apathy affects up to a third of ALS patients аnd develops in the context of progressive neurodegeneration. Increased awareness and understanding of non-motor symptoms in ALS highlights the potential utility of apathy as an outcome measure in future clinical trial design.

Norwegian version of the Edinburgh cognitive and behavioural ALS screen: Construct validity, internal consistency, inter-rater, and test-retest reliability

BACKGROUND

Research collaboration highlight a need for validated tests in other languages than English. Translation and culture adjustments may threaten essential features of the original instrument.

OBJECTIVE

To assess the internal consistency, inter-rater and test-retest reliability, and construct validity of the Norwegian version of the Edinburgh Cognitive and Behavioural Amyotrophic Lateral Sclerosis (ALS) Screen (ECAS-N).

METHODS

Performance of 71 subjects with ALS, 85 healthy controls (HC) and 6 controls with Alzheimer's disease (AD) were assessed with the ECAS-N. Test-retest interval was four months. Internal consistency was evaluated using Cronbach's alpha; reliability was assessed using intraclass correlation coefficient (ICC), Cohen's kappa, and Bland Altman plot. Five hypothesis, including the Montreal Cognitive Assessment (MoCA) screen, was evaluated for construct validity.

RESULTS

ECAS-N total score produced a Cronbach's alpha of 0.65, had excellent inter-rater reliability (ICC = 0.99) and acceptable test-retest reliability (ICC = 0.73). Construct validity analysis suggested valid use of the ECAS-N to distinguish people with ALS-specific cognitive impairment from HC (p = 0.001) and those with AD (p = 0.002). The MoCA and ECAS-N were moderately correlated (r = 0.53).

CONCLUSION

The ECAS-N has potential to be used by different testers in clinical practice and research to screen patients with ALS who speak Norwegian and for documenting cognitive impairment over time.

Mild behavioral impairment as a potential marker of predementia risk states in motor neuron diseases

BACKGROUND AND PURPOSE

Mild behavioral impairment (MBI) has been increasingly regarded as the neurobehavioral axis of predementia risk states, but a specific investigation of its detection as a potential marker of prodromal dementia in motor neuron diseases (MNDs) is still lacking. The aims of our study were therefore to explore MBI in MNDs both at onset and over the disease course, and to evaluate its relationship with baseline and longitudinal cognitive features.

METHODS

Sixty MND patients with cognitive/behavioral, mood, and motor examinations were recruited and followed longitudinally for up to 15 months. Associations between baseline MBI symptoms and clinical features were tested using the Spearman correlation coefficient. Based on longitudinal data, relative deltas of variation for each cognitive measure were generated, and linear regression models were then used to evaluate the role of baseline MBI symptoms in predicting longitudinal rates of cognitive decline.

RESULTS

At disease onset, the most impaired MBI domain was affective/emotional dysregulation, followed by impulse dyscontrol, apathy, and social inappropriateness. Greater MBI symptoms correlated with more severe baseline motor, cognitive/behavioral, and mood disturbances (p values from <0.001 to 0.05). Longitudinally, the greatest decline was observed in the affective/emotional dysregulation domain, followed by impulse dyscontrol, apathy, and social inappropriateness. Greater MBI symptoms at onset were significant predictors of more severe longitudinal cognitive decline in both amyotrophic lateral sclerosis (ALS)-specific and ALS-nonspecific functions (p values from <0.001 to 0.03).

CONCLUSIONS

MBI represents a valuable clinical marker of incident cognitive decline in MNDs, and its evaluation has good potential for detecting dementia in its preclinical/prodromal phase.

Defining cognitive impairment in amyotrophic lateral sclerosis: an evaluation of empirical approaches

Objective: Amyotrophic lateral sclerosis (ALS) is a multi-system disorder characterized primarily by motor neuron degeneration, but may be accompanied by cognitive dysfunction. Statistically appropriate criteria for establishing cognitive impairment (CI) in ALS are lacking. We evaluate quantile regression (QR), that accounts for age and education, relative to a traditional two standard deviation (SD) cutoff for defining CI. Methods: QR of cross-sectional data from a multi-center North American Control (NAC) cohort of 269 healthy adults was used to model the 5th percentile of cognitive scores on the Edinburgh Cognitive and Behavioral ALS Screen (ECAS). The QR approach was compared to traditional two SD cutoff approach using the same NAC cohort (2SD-NAC) and to existing UK-based normative data derived using the 2SD approach (2SD-UK) to assess the impact of cohort selection and statistical model in identifying CI in 182 ALS patients. Results: QR-NAC models revealed that age and education impact cognitive performance on the ECAS. Based on QR-NAC normative cutoffs, the frequency of CI in the 182 PENN ALS patients was 15.9% for ALS specific, 12.6% for ALS nonspecific, and 15.4% for ECAS total. This frequency of CI is substantially more conservative in comparison to the 2SD-UK (20.3%-34.6%) and modestly more conservative to the 2SD-NAC (14.3%-16.5%) approaches for estimating CI. Conclusions: The choice of normative cohort has a substantial impact and choice of statistical method a modest impact on defining CI in ALS. This report establishes normative ECAS thresholds to identify whether ALS patients in the North American population have CI.

Translation, cultural adaptation, and validation of a screening test for cognitive and behavioural changes in amyotrophic lateral sclerosis

PURPOSE

To describe challenges of translating and culturally adapting the Edinburgh Cognitive and Behavioural Amyotrophic Lateral Sclerosis (ALS) Screen into Norwegian (ECAS-N), evaluate its content validity; provide age- and education-balanced norms for verbal fluency and cut-off values for abnormal performance.

MATERIALS AND METHODS

Translation to Norwegian and back-translation to English complied with standard methods. Patients and ALS experts evaluated the relevance, comprehensiveness and comprehensibility of the translated ECAS (ECAS-N). Content validity indexes at the item level (I-CVI), scale level (S-CVI) and inter-rater agreement were calculated. Performance of controls determined norms for written and spoken verbal fluency (n = 559) and cut-off scores for abnormal performance (n = 85).

RESULTS

High levels of content validity was achieved for all items of the ECAS-N, I-CVI, S-CVI and inter-rater agreement was 87.5%. Age- and education-balanced norms for written and spoken verbal fluency were produced. Cut-off scores of abnormal performance were slightly lower than the original ECAS.

CONCLUSIONS

The ECAS-N holds promise for detecting cognitive and behavioural impairment in Norwegian patients with ALS. Cut-off scores are situational and could slightly vary between different cultures. The ECAS-N can be used in international research, but researchers should be aware of the differences between the tests applied in the studies.Implications for rehabilitationThe ECAS-N, a Norwegian version of the English-language ECAS was produced for clinical use in Norway.Rigorous translation methods were used, and expert-judged modifications were made for Norwegian-specific culture and language nuances.Determination of ECAS-N cut-off scores for abnormal cognition was guided by a biostatistician, are slightly lower than the original ECAS, and are based on results from an objectively calculated number of healthy Norwegians.A nuanced picture of cognitive impairment in ALS drawn from a well-developed scale as the ECAS-N can contribute to a management process better tailored to patients'- and carers' individual needs.

Medulla oblongata volume as a promising predictor of survival in amyotrophic lateral sclerosis

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Brainstem volumes reflect the disease severity expressed as ALSFRS-r (total score and its bulbar and spinal subscores).

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Medulla oblongata volume demonstrated a significant accuracy to discriminate long and short survivors ALS patients.

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Brainstem volumes may reflect the impairment of corticospinal and corticobulbar tracts as well as lower bulbar motor neurons. Furthermore, medulla oblongata could be used as an early predictor of survival in ALS patients.

Background

Unconventional magnetic resonance imaging studies of the brainstem have recently acquired a growing interest in amyotrophic lateral sclerosis (ALS) pathology since they provide a unique opportunity to evaluate motor tract degeneration and bulbar lower motor neuron involvement. The aim of this study was to investigate the role of brainstem structures as accurate biomarkers of disease severity and predictors of survival.

Materials and Methods

A total of 60 ALS patients and 30 healthy controls subjects (CS) were recruited in this study. Patients were divided in two subgroups according to the onset of the disease: 42 spinal (S-ALS) and 18 bulbar (B-ALS). All subjects underwent 3D-structural MRI. Brainstem volume both of the entire cohort of ALS patients and S-ALS and B-ALS onset were compared with those of CS. In addition the two ALS subgroups were tested for differences in brainstem volumes.

Volumetric, vertex-wise, and voxel-based approaches were implemented to assess correlations between MR structural features and clinical characteristics expressed as ALSFRS-r and its bulbar (ALSFSR-r-B) and spinal subscores (ALSFSR-r-S). ROC curves were performed to test the accuracy of midbrain, pons, and medulla oblongata volumes able to discriminate patients dichotomized into long and short survivors by using Two-Steps cluster analysis. Univariate and multivariate survival analyses were carried out to test the prognostic role of brainstem structures’ volume, trichotomized by applying a k-means clustering algorithm.

Results

Both the entire cohort of ALS patients and B-ALS and S-ALS showed significant lower volumes of both medulla oblongata and pons compared to CS. Furthermore, B-ALS showed a significant lower volume of medulla oblongata, compared to S-ALS. Lower score of ALSFRS-r correlated to atrophy in the anterior compartment of midbrain, pons, and medulla oblongata, as well as in the posterior portion of only this latter region. ALSFSR-r-S positively correlated with shape deformation and density reduction of the anterior portion of the entire brainstem, along the corticospinal tracts. ALSFSR-r-B instead showed a positive correlation with shape deformation of the floor of the fourth ventricle in the medulla oblongata and the crus cerebri in the midbrain. Only medulla oblongata volume demonstrated a significant accuracy to discriminate long and short survivors ALS patients (ROC AUC 0.76, p < 0.001). Univariate and multivariate analysis confirmed the survival predictive role of the medulla oblongata (log rank test p: 0.003).

Discussions

Our findings suggest that brainstem volume may reflect the impairment of corticospinal and corticobulbar tracts as well as lower bulbar motor neurons. Furthermore, medulla oblongata could be used as an early predictor of survival in ALS patients.

The diagnostic value of the Italian version of the Edinburgh Cognitive and Behavioral ALS Screen (ECAS)

Objectives: The diagnostic capabilities of specific cognitive screeners are clinically crucial for an early detection of frontotemporal features in amyotrophic lateral sclerosis (ALS) patients. This study aimed at providing diagnostic properties of the cognitive section of the Edinburgh Cognitive and Behavioral ALS Screen (ECAS) in Italian ALS patients.Methods: Eighty-nine consecutive Italian ALS patients were classified according to Strong et al. (2017) criteria with a comprehensive neuropsychological assessment. The Italian version of ECAS was also administered, and its accuracy, sensitivity (SE), specificity (SP), negative and positive predictive values (PPV; NPV) and likelihood ratios (LR+; LR-) were computed against clinical diagnoses.Results: The ECAS and its subscales yielded moderate-to-high accuracy (AUC = .7-.87). High SP was overall found (81.8%-100%). The most sensitive measures were ALS-specific and Executive (73.9-78.3%) subscales, while the least were the ALS-non-specific subscales (8.7-17.4%). ECAS measures showed good PPVs (60%-100%) and NPVs (75.9%-91.5%). Acceptable LRs were found (LR+: 6.97-4.3; LR-: .29-.91), with total and ALS-specific measures yielding the best estimates.Conclusions: This is the first study demonstrating the diagnostic value of the ECAS against a thorough neuropsychological assessment in Italy. ECAS-total and -ALS-specific scores are diagnostically sound as to both intrinsic and post-test features, whereas ALS-non-specific measures perform slightly worse.

Developments in the assessment of non-motor disease progression in amyotrophic lateral sclerosis

INTRODUCTION

The burden of non-motor symptoms is a major determinant of quality of life and outcome in amyotrophic lateral sclerosis (ALS) and has profound negative effect also on caregivers.

AREAS COVERED

Non-motor symptoms in ALS include cognitive impairment, neurobehavioral symptoms, depression and anxiety, suicidal ideation, pain, disordered sleep, fatigue, weight loss and reduced appetite, and autonomic dysfunctions. This review summarizes the measures used for the assessment of non-motor symptoms and their properties and recaps the frequency and progression of these symptoms along the course of ALS.

EXPERT OPINION

Non-motor symptoms in ALS represent a major component of the disease and span over several domains. These symptoms require a high level of medical attention and should be checked at each visit using ad hoc questionnaires and proactively treated. Several instruments assessing non-motor symptoms have been used in ALS. Specific screening questionnaires for non-motor symptoms can be used for monitoring patients during telehealth visits and for remote surveillance through sensors and apps installed on smartphones. Novel trials for non-motor symptoms treatment specifically designed for ALS are necessary to increase and refine the therapeutic armamentarium. Finally, scales assessing the most frequent and burdensome non-motor symptoms should be included in clinical trials.

Cognitive and behavioural impairment in amyotrophic lateral sclerosis: A landmark of the disease? A mini review of longitudinal studies

Amyotrophic lateral sclerosis (ALS) is a heterogeneous neurodegenerative disease marked by progressive loss of motor abilities. Approximately half of patents with ALS experience cognitive (ALSci) or behavioural impairment (ALSbi) during the course of the disease, with a small percentage developing overt frontotemporal dementia (FTD). ALSci and/or ALSbi can occur simultaneously with motor neuron degeneration or develop in advanced stages of the disease, but it can even precede motor involvement in some cases, namely in ALS patients meeting criteria for FTD. Despite clear evidence that cognitive/behavioural impairment may appear early in the course of ALS, no prominent deterioration seems to occur with disease progression. Longitudinal studies have failed to reach conclusive results on the progression of cognitive and behavioural involvement in ALS. This may be due to some structural limitations of the studies, such as attrition rate, practice effect, short-time interval between neuropsychological assessments, but it can also be due to the heterogeneity of ALS phenotypes. The objective of this review is to provide a comprehensive and critical analysis of results of longitudinal studies highlighting cognitive and behavioural domains mainly affected by neurodegeneration pointing out the determinants that might be associate with the development and worsening of frontotemporal symptoms in ALS. At this regard, older age, rapidly progressing ALS, bulbar-onset, advanced disease stages are among factors mainly associated with cognitive and behavioural involvement. Moreover, the progression of cognitive and behavioural deficits seems to be not directly related to the slope of motor disability, thus suggesting the independence of neuropsychological and motor functional decline in ALS. Cognitive and motor involvement may indeed present with distinct trajectories suggesting a differential vulnerability of motor and non-motor cortical networks. In this scenario, determining the progression of extra-motor involvement in ALS may help refine understanding of the clinical implications of cognitive and behavioural abnormalities, and provide clues to the aetiology of the disease.

Cognitive dysfunction in amyotrophic lateral sclerosis: can we predict it?

Background and aim

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder characterized by the degeneration of both upper and lower motoneurons in the brain and spinal cord leading to motor and extra-motor symptoms. Although traditionally considered a pure motor disease, recent evidences suggest that ALS is a multisystem disorder. Neuropsychological alterations, in fact, are observed in more than 50% of patients: while executive dysfunctions have been firstly identified, alterations in verbal fluency, behavior, and pragmatic and social cognition have also been described. Detecting and monitoring ALS cognitive and behavioral impairment even at early disease stages is likely to have staging and prognostic implications, and it may impact the enrollment in future clinical trials. During the last 10 years, humoral, radiological, neurophysiological, and genetic biomarkers have been reported in ALS, and some of them seem to potentially correlate to cognitive and behavioral impairment of patients. In this review, we sought to give an up-to-date state of the art of neuropsychological alterations in ALS: we will describe tests used to detect cognitive and behavioral impairment, and we will focus on promising non-invasive biomarkers to detect pre-clinical cognitive decline.

Conclusions

To date, the research on humoral, radiological, neurophysiological, and genetic correlates of neuropsychological alterations is at the early stage, and no conclusive longitudinal data have been published. Further and longitudinal studies on easily accessible and quantifiable biomarkers are needed to clarify the time course and the evolution of cognitive and behavioral impairments of ALS patients.

Compensating for verbal-motor deficits in neuropsychological assessment in movement disorders: sensitivity and specificity of the ECAS in Parkinson's and Huntington's diseases

INTRODUCTION

The study aims at investigating psychometric properties of the Edinburgh cognitive and behavioural ALS screen (ECAS) in Parkinson's (PD) and Huntington's (HD) diseases. The sensitivity and specificity of the ECAS in highlighting HD and PD cognitive-behavioural features and in differentiating between these two populations and from healthy controls (HC) were evaluated. Moreover, correlations between the ECAS and traditional cognitive measures, together with core clinical features, were analysed.

METHODS

Seventy-three PD patients, 38 HD patients, and 49 education-matched healthy participants were enrolled. Participants were administered the ECAS, together with other cognitive screening tools and psychological questionnaires. Patients' behavioural assessment was also carried out with carers.

RESULTS

The ECAS distinguished between HD patients and HC and between the two clinical syndromes with high sensitivity and specificity. Even if the diagnostic accuracy of the ECAS in distinguishing between PD and HC was low, the PD cognitive phenotype was very well described by the ECAS performances. Convergent validity of the ECAS against other traditional cognitive screening was observed, as well as correlations with psychological aspects and typical clinical features, especially for the HD group.

CONCLUSIONS

The ECAS represents a rapid and feasible tool, useful also in other neurodegenerative disorders affecting verbal-motor abilities than the amyotrophic lateral sclerosis such as PD and HD. Clinical applications in these neurodegenerative conditions require further investigations and, probably, some adaptations of the original test.

Longitudinal clinical and neuroanatomical correlates of memory impairment in motor neuron disease

Memory impairment in motor neuron disease (MND) is still an underrecognized feature and has traditionally been attributed to executive dysfunction. Here, we investigate the rate of memory impairment in a longitudinal cohort of MND patients, its relationship to other cognitive functions and the underlying neuroanatomical correlates. 142 patients with MND and 99 healthy controls (HC) underwent comprehensive neuropsychological testing and structural MRI at 3T up to four times over a period of 18 months. Linear-mixed effects models were fitted to identify changes at baseline and over time in episodic memory function (learning, immediate and delayed recall, recognition), composed cognitive scores (memory, verbal fluency, executive function), and memory-related structural brain regions (hippocampus, entorhinal cortex, parahippocampal gyrus). Associations between episodic memory performance and volumetric or cortical thickness changes of these regions were computed using Pearson's r. Learning, immediate and delayed recall, as well as recognition performance were significantly reduced in MND when compared to controls at baseline. Performances in these subtests improved over time although MND showed less improvement than controls. This relationship did not change when only "classical" ALS patients were considered. Patients with MND showed thinning of the right parahippocampal gyrus (PhG) in comparison to controls that was progressing over time. Bilateral hippocampal atrophy was observed in MND patients with memory impairment after splitting the group according to their overall episodic memory performance, with the right hippocampus shrinking over time. In MND patients, the bilateral hippocampal atrophy was associated with impairment in learning, recall, and recognition at baseline. In contrast, left PhG thinning was associated with a poorer learning performance. These results show that episodic memory impairment in MND is a frequent cognitive dysfunction. Since deficits are not clearly declining with disease course, an early involvement of this cognitive domain in the disease seems probable. The memory performance-dependent atrophy of the hippocampus and PhG provide evidence for a widespread involvement of these non-motor cortical areas in disease pathology.

Metabolic brain changes across different levels of cognitive impairment in ALS: a 18F-FDG-PET study

OBJECTIVE

To identify the metabolic changes related to the various levels of cognitive deficits in amyotrophic lateral sclerosis (ALS) using 18F-2-fluoro-2-deoxy-D-glucose positron emission tomography (18F-FDG-PET) imaging.

METHODS

274 ALS patients underwent neuropsychological assessment and brain 18F-FDG-PET at diagnosis. According to the criteria published in 2017, cognitive status was classified as ALS with normal cognition (ALS-Cn, n=132), ALS with behavioural impairment (ALS-Bi, n=66), ALS with cognitive impairment (ALS-Ci, n=30), ALS with cognitive and behavioural impairment (ALS-Cbi, n=26), ALS with frontotemporal dementia (ALS-FTD, n=20). We compared each group displaying some degree of cognitive and/or behavioural impairment to ALS-Cn patients, including age at PET, sex and ALS Functional Rating Scale-Revised as covariates.

RESULTS

We identified frontal lobe relative hypometabolism in cognitively impaired patients that resulted more extensive and significant across the continuum from ALS-Ci, through ALS-Cbi, to ALS-FTD. ALS-FTD patients also showed cerebellar relative hypermetabolism. ALS-Bi patients did not show any difference compared with ALS-Cn.

CONCLUSIONS

These data support the concept that patients with cognitive impairment have a more widespread neurodegenerative process compared with patients with a pure motor disease: the more severe the cognitive impairment, the more diffuse the metabolic changes. Otherwise, metabolic changes related to pure behavioural impairment need further characterisation.

The 6-min walk test as a new outcome measure in Amyotrophic lateral sclerosis

One of the issues highlighted in amyotrophic lateral sclerosis (ALS) clinical trials is the lack of appropriate outcome measures. The aim of this multicentric study was to evaluate the 6-min walk test (6MWT) as tool to monitor the natural history of a cohort of ALS patients followed up over a 6-month interval. Forty-four ambulant patients were assessed at baseline and after 1, 3 and 6 months. Eight out of forty-four lost the ability to walk before the end of the study. The 6MWT and the objective measures linked to motor function, such as 10 m walking test (10MWT) and Time-up and go (TUG), the ALSFRS-R and the ALSFRS-R items 7–9 showed a good responsiveness to change over the 6-month interval. There was a strong correlation between 6 and 10MWT, TUG, ALSFRS-R, ALSFRS-R items 7–9 and FVC% at baseline. There was no correlation with Edinburgh Cognitive and Behavioural ALS Screen (ECAS) and Modified Borg Scale (MBS). The Δ of 6MWT from T0 to T6 significantly correlated with the Δs of 10MWT and TUG. There was no correlation with the Δs of ALSFRS-R, ALSFRS-R items 7 9, ECAS, MBS and FVC%. The discordance between changes of the 6MWT and ALSFRS-R at 6 month highlights the different content validity among these instruments. The concordance among 6MWT, 10MWT and TUG indicates that the 6MWT is an objective, sensitive and robust tool to measure motor performances in a longitudinal setting. The main limitations of our study were the small sample size and the high percentage of patients (18%) lost at follow-up. Therefore, further studies on larger cohorts, and exploring the relation between 6MWT and need of ventilator support or survival could strengthen our results.

Psychometric Properties of Cognitive Assessment in Amyotrophic Lateral Sclerosis: A Systematic Review

Purpose

We aimed to list all tests used to assess cognitive change in patients with amyotrophic lateral sclerosis (ALS) and to provide a descriptive synthesis of the psychometric properties of tests that were evaluated in a population of ALS patients.

Materials and Methods

The protocol is registered in PROSPERO (ID: CRD42017055603). We systematically search for literature in 11 databases. Full-text articles, in any language, with original research were included. All included articles were scrutinised by two independent authors. Disagreement was resolved by consensus. The framework of Lezak informed conceptualises of the tests identified. To evaluate methodological quality, we used the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN). Data were synthesised using criteria proposed by the Cochrane Back Review Group.

Results

Of 319 included articles, 46 articles reported information on the psychometric properties of cognitive tests used in patients with ALS. We found that the highest level of evidence was supported for the Reading the Mind in the Eye Test (RME), Addenbrooke’s Cognitive Evaluation (ACE) and Frontal Assessment Battery (FAB). Moderate level of evidence was found for the screening tests; Edinburgh Cognitive and Behavioural ALS Screen (ECAS) and the Montreal Cognitive Assessment (MoCA).

Conclusion

The screening test, ECAS and the social cognition test, RME, may have some advantages over other tests that have been used for assessing cognitive change in ALS patients. Recommendations of ALS-specific tests with sound psychometric properties are urgently needed.

Decline of cognitive and behavioral functions in amyotrophic lateral sclerosis: a longitudinal study

Background: A cognitive impairment, ranging from frontotemporal dementia (FTD) to milder forms of dysexecutive or behavioral dysfunction, is detected in 30-50% of patients affected by amyotrophic lateral sclerosis (ALS) at diagnosis. Such condition considerably influences the prognosis, and possibly impacts on the decision-making process with regards to end-of-life choices. The aim of our study is to examine the changes of cognitive and behavioral impairment in a large population of ALS from the time of diagnosis to a 6-month follow-up (IQR 5.5-9.0 months), and to examine to what extent the progression of cognitive impairment affects survival time and rate of disease progression.Methods: We recruited 146 ALS patients classified according to revised criteria of ALS and FTD spectrum disorder. In a multidisciplinary setting, during two subsequent visits we examined clinical features with ALSFRS-r score, FVC% and BMI, and cognitive status with an extensive neuropsychological evaluation.Results: At second examination, one-third of patients showed a worsening of cognitive impairment, namely 88% of ALSbi, 27% of ALSci, 40% of ALScbi, and, interestingly, also 24% of cognitive normal ALS developed a significant cognitive dysfunction. We find that those who changed their cognitive status presented a lower ALSFRS-r score at t1 and a shorter survival time compared to those who did not change, regardless of the type of cognitive impairment.Conclusion: We show how cognitive disorders in ALS patients can not only be present at diagnosis, but also manifest during disease and influence the progression of motor deficit and the prognosis.

An overview of screening instruments for cognition and behavior in patients with ALS: selecting the appropriate tool for clinical practice

Objective: Patients with amyotrophic lateral sclerosis (ALS) not only show motor deficits, but may also have cognitive and/or behavioral impairments. Recognizing these impairments is crucial as they are associated with lower quality of life, shorter survival, and increased caregiver burden. Therefore, ALS-specific neuropsychological screening instruments have been developed that can account for motor and speech difficulties. This study provides an overview and comparison of these screeners. Methods: A systematic review was conducted using Medline and Embase. Articles describing cognitive/behavioral screening instruments assessed in ALS patients were included. Screening instruments were compared on multiple factors, such as domains, adaptability, required time, and validation. Results: We included 99 articles, reporting on nine cognitive screeners (i.e. ACE-R, ALS-BCA, ALS-CBS, ECAS, FAB, MMSE, MoCA, PSSFTS, and UCSF-SB), of which five ALS-specific. Furthermore, eight behavioral screeners (i.e. ALS-FTD-Q, AES, BBI, DAS, FBI, FrSBe, MiND-B, and NPI) were reported on, of which three ALS-specific. Conclusion: Considering the broad range of cognitive domains, adaptability, and satisfying validity, the ALS-CBS and ECAS appear to be the most suitable screeners to detect cognitive and behavioral changes in ALS. The BBI appears to be the best option to screen for behavioral changes in ALS, since all relevant domains are assessed, motor-related problems are considered, and has a satisfactory validity. The MiND-B and ALS-FTD-Q are promising as well. In general, all screening instruments would benefit from additional validation research to gain greater insights into test characteristics and to aid clinicians in selecting screening tools for use in clinical practice.

ALS Cognitive Behavioral Screen (ALS-CBS): normative values for the Italian population and clinical usability

Amyotrophic lateral sclerosis (ALS) patients often express cognitive and behavioral dysfunctions within the so-called "frontotemporal spectrum disorders." Guidelines recommend screening of such dysfunctions, albeit only ALS dedicated tools are eventually suitable, due to the profound motor limitations induced by the disease. ALS Cognitive Behavioral Screen (ALS-CBS) is such a screening tool but normative data are not available, limiting its widespread implementation. Our aim consisted in producing normative data for the Italian version of the ALS-CBS. The scale was administered to n = 458 healthy controls with different age and education. Following translation and back translation of the original version of the test, normative data and correction scores for the ALS-CBS cognitive subtest (ALS-CBSci) were generated. Furthermore, n = 100 ALS consecutive outpatients with a wide range of cognitive and motor severity underwent to the ALS-CBS, besides FAB and Weigl sorting test (WST), in order to check its usability. Completion rate was 100% for ALS-CBS and WST, and 68% for the FAB. Corrected ALS-CBS scores showed 12% detection rate of significant cognitive dysfunction with a moderate kappa with FAB and WST. For the ALS-CBS behavioral subtest (ALS-CBSbi), a caregiver was available for n = 81 ALS patients and asked to complete the subset. The detection rate for behavioral dysfunction was 55.5%, and a mild correlation between with the Caregiver Burden Inventory was present (r = - 0.26, p = 0.04). In conclusion, we offer here normative data for the ALS-CBS, a handy tool for screening frontotemporal spectrum dysfunctions in ALS patients, and confirm its usability and validity in an outpatient setting.

Cognitive, Emotional and Psychological Manifestations in Amyotrophic Lateral Sclerosis at Baseline and Overtime: A Review

It is now well recognized that, in addition to motor impairment, amyotrophic lateral sclerosis (ALS) may cause extra-motor clinical signs and symptoms. These can include the alteration of certain cognitive functions, impaired social cognition, and changes in the perception and processing of emotions. Where these extra-motor manifestations occur in ALS, they usually do so from disease onset. In about 10% of cases, the cognitive and behavioral changes meet the diagnostic criteria for frontotemporal dementia. The timecourse of behavioral and cognitive involvement in ALS is unclear. Whereas longitudinal studies have failed to show cognitive decline over time, some cross-sectional studies have demonstrated poorer cognitive performances in the advanced stages of the disease. Neuroimaging studies show that in ALS, extra-motor signs and symptoms are associated with specific brain lesions, but little is known about how they change over time. Finally, patients with ALS appear less depressed than might be expected, given the prognosis. Moreover, many patients achieve satisfactory psychosocial adjustment throughout the course of the disease, regardless of their degree of motor disability. There are scant longitudinal data on extra-motor impairment in ALS, and to our knowledge, no systematic review on this subject has yet been published. Even so, a better understanding of patients' clinical trajectory is essential if they are to be provided with tailored care and given the best possible support. We therefore undertook to review the evidence for extra-motor changes and their time course in ALS, in both the cognitive, emotional and psychological domains, with a view to identifying mechanisms that may help these patients cope with their disease.

Cognitive impairment across ALS clinical stages in a population-based cohort

OBJECTIVE

To assess the association of the degree of severity of motor impairment to that of cognitive impairment in a large cohort of patients with amyotrophic lateral sclerosis (ALS).

METHODS

This is a population-based cross-sectional study on patients with ALS incident in Piemonte, Italy, between 2007 and 2015. Cognitive status was classified according to the revised ALS-FTD Consensus Criteria. The King system and the Milano Torino Staging system (MiToS) were used for defining the severity of motor impairment.

RESULTS

Of the 797 patients included in the study, 163 (20.5%) had ALS-frontotemporal dementia (FTD), 38 (4.8%) cognitive and behavioral impairment (ALScbi), 132 (16.6%) cognitive impairment (ALSci), 63 (7.9%) behavioral impairment (ALSbi), 16 (2.0%) nonexecutive impairment, and 385 (48.2%) were cognitively normal. According to King staging, the frequency of cases with ALS-FTD progressively increased from 16.5% in stage 1-44.4% in stage 4; conversely, the frequency of ALSci, ALSbi, and ALScbi increased from King stage 1 to King stage 3 and decreased thereafter. A similar pattern was observed with the MiToS staging. ALS-FTD was more frequent in patients with bulbar involvement at time of cognitive testing. Patients with C9ORF72 expansion (n = 61) showed more severe cognitive impairment with increasing King and MiToS stages.

CONCLUSION

Our findings suggest that ALS motor and cognitive components may worsen in parallel, and that cognitive impairment becomes more pronounced when bulbar function is involved. Our data support the hypothesis that ALS pathology disseminates in a regional ordered sequence, through a cortico-efferent spreading model.

Tracking a Fast-Moving Disease: Longitudinal Markers, Monitoring, and Clinical Trial Endpoints in ALS

Amyotrophic lateral sclerosis (ALS) encompasses a heterogeneous group of phenotypes with different progression rates, varying degree of extra-motor involvement and divergent progression patterns. The natural history of ALS is increasingly evaluated by large, multi-time point longitudinal studies, many of which now incorporate presymptomatic and post-mortem assessments. These studies not only have the potential to characterize patterns of anatomical propagation, molecular mechanisms of disease spread, but also to identify pragmatic monitoring markers. Sensitive markers of progressive neurodegenerative change are indispensable for clinical trials and individualized patient care. Biofluid markers, neuroimaging indices, electrophysiological markers, rating scales, questionnaires, and other disease-specific instruments have divergent sensitivity profiles. The discussion of candidate monitoring markers in ALS has a dual academic and clinical relevance, and is particularly timely given the increasing number of pharmacological trials. The objective of this paper is to provide a comprehensive and critical review of longitudinal studies in ALS, focusing on the sensitivity profile of established and emerging monitoring markers.