Validation of the Neuronorma battery for neuropsychological assessment in multiple sclerosis

European cross-cultural neuropsychological test battery (CNTB) for the assessment of cognitive impairment in multiple sclerosis: Cognitive phenotyping and classification supported by machine learning techniques

BACKGROUND

The European Cross-Cultural Neuropsychological Test Battery (CNTB) has been proposed as a comprehensive battery for cognitive assessment, reducing the potential impact of cultural variables. In this validation study, we aimed to evaluate the diagnostic capacity of CNTB for the assessment of participants with multiple sclerosis (pwMS) compared to the Neuronorma battery (NN) according to the International Classification of Cognitive Disorders in MS criteria, and to develop machine learning (ML) algorithms to improve the diagnostic capacity of CNTB and to select the most relevant tests.

METHODS

Sixty pwMS and 60 healthy controls (HC) with no differences in sex, age, or years of education were enrolled. All participants completed the CNTB and pwMS were also examined with NN, depression, and fatigue scales. Impaired domains and cognitive phenotypes were defined following ICCoDiMS based on CNTB scores and compared to NN, according to -1SD and -1.5SD cutoff scores. To select the most relevant tests, random forest (RF) was performed for different binary classifications.

RESULTS

PwMS showed a lower performance compared to HC with medium-large effect sizes, in episodic memory, executive function, attention, and processing speed, in accordance with their characteristic cognitive profile. There were no differences in impaired domains or cognitive phenotypes between CNTB and NN, highlighting the role of episodic memory, executive function, attention, and processing speed tests. The most relevant tests identified by RF were consistent with inter-group comparisons and allowed a better classification than SD cutoff scores.

CONCLUSION

CNTB is a valid test for cognitive diagnosis in pwMS, including key tests for the most frequently impaired cognitive domains in MS. The use of ML techniques may also be useful to improve diagnosis, especially in some tests with lower sensitivity.

Cognitive dysfunction characteristics of multiple sclerosis with aging

BACKGROUND

We aimed to investigate the characteristics of cognitive impairment in older people with multiple sclerosis (MS).

METHODS

Cross-sectional study that included participants that were examined with a common and comprehensive neuropsychological protocol. The subjects were matched by sociodemographic variables and the following groups were generated for comparisons: young MS versus healthy controls (HC) (n = 246), old MS versus HC (n = 198), young MS vs old MS (n = 226), MS vs Alzheimer's disease (AD)(n = 70), and MS vs Parkinson's disease (PD) (n = 62). The ICCoDiMS criteria were used to define cognitive impairment in MS.

RESULTS

Cognitive impairment was more frequent in young than old patients (70.8 % vs 52.2 %). Attention and speed processing is the most frequent cognitive domain impaired in MS (54.9 % of young MS vs 32.7 % of old MS). The frequency of impairment in attention/processing speed (54.9 % vs 32.7 %) and episodic memory (27.9 % vs 14.3) was higher in the young group than in the old group. There were no statistically significant differences in the distribution of impairment in executive function (46.0 % vs 35.3 %), visuospatial (17.9 % vs 9.5 %), and language (12.4 % vs 17.7 %). In those patients meeting the criteria for cognitive impairment, young MS patients showed lower performance in attention/processing speed tests. Conversely, old MS patients showed lower performance in episodic memory, verbal fluency, and planning. There were no differences in the correlations between SDMT and other neuropsychological tests in young and old patients, which suggests similar cognitive processes underlying SDMT performance in both groups. There were differences between old MS and prodromal AD, especially in episodic memory, while the cognitive profile of old MS was largely shared with PD.

CONCLUSIONS

Our study found that the cognitive profile of MS is defined by a characteristic impairment in attention and processing speed, which is present during the lifespan. The impairment in processing speed is less prominent in old age, whereas the impairment of other cognitive functions becomes more relevant. These findings suggest potential differences in the pathophysiological processes associated with cognitive impairment between young and old ages that warrant further investigation.

Cognitive profile in multiple sclerosis and post-COVID condition: a comparative study using a unified taxonomy

Post-COVID condition (PCC) and multiple sclerosis (MS) share some clinical and demographic features, including cognitive symptoms and fatigue. Some pathophysiological mechanisms well-known in MS, such as autoimmunity, neuroinflammation and myelin damage, have also been implicated in PCC. In this study, we aimed to compare the cognitive phenotypes of two large cohorts of patients with PCC and MS, and to evaluate the relationship between fatigue and cognitive performance. Cross-sectional study including 218 patients with PCC and 218 with MS matched by age, sex, and years of education. Patients were evaluated with a comprehensive neuropsychological protocol and were categorized according to the International Classification of Cognitive Disorders system. Fatigue and depression were also assessed. Cognitive profiles of PCC and MS largely overlapped, with a greater impairment in episodic memory in MS, but with small effect sizes. The most salient deficits in both disorders were in attention and processing speed. The severity of fatigue was greater in patients with PCC. Still, the correlations between fatigue severity and neuropsychological tests were more prominent in the case of MS. There were no differences in the severity of depression among groups. Our study found similar cognitive profiles in PCC and MS. Fatigue was more severe in PCC, but was more associated with cognitive performance in MS. Further comparative studies addressing the mechanisms related to cognitive dysfunction and fatigue may be of interest to advance the knowledge of these disorders and develop new therapies.

Validation of the Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS) in individuals with multiple sclerosis from Mexico

BACKGROUND

Cognitive impairment is observed in 43-70 % of Multiple sclerosis (MS) patients. One of the most widely used batteries for cognitive assessment in this population is the Brief International Cognitive Assessment for MS (BICAMS). The objective of this study was to validate and assess the reliability of the BICAMS in a Mexican population with MS and to obtain and provide regression-based norms.

METHODS

One hundred healthy controls (HCs) and 100 patients with multiple sclerosis participated in the present study, and groups were matched for age, years of education and sex. Subjects completed all three tests of the BICAMS. Test-retest measures were obtained from 30 patients to test reliability.

RESULTS

The sample´s average age was 43.39 ± 6.03 years old, and the average years of education was 12.55 ± 2.52 years. Approximately 63 % of the participants were female. The groups did not differ in age, years of education, or sex. The MS group performed significantly worse than the HCs group on all three neuropsychological tests. A significant difference was observed for the SDMT (t = 10.166; p=<0.001), CVLT-II (t = 10.949; p=<0.001), and BVMT-R (t = 2.636; p = 0.009). For all comparisons, the effect size (d) for each test was calculated as follows: SDMT= 0.58 and CVLT-II= 0.61. The test-retest coefficients for each test were as follows: SDMT: r = 0.95; CVLT-II: r = 0.84; and BVMT-R = 0.81.

CONCLUSION

The BICAMS can provide information on cognitive impairment in MS patients, and this information can be used by neuropsychologists for cognitive rehabilitation in different domains.

Effects of exergaming on cognition, lower limb functional coordination, and stepping time in people with multiple sclerosis: a randomized controlled trial

PURPOSE

To compare the effects of exergaming versus conventional exercises on cognition, lower-limb functional coordination, and stepping time in people with multiple sclerosis (PwMS).

METHODS

Thirty-six PwMS were randomly assigned to either intervention (n = 18) or control (n = 18) group and received 18 training sessions during six weeks. The intervention group performed exergames that required multidirectional timed-stepping, weight-shifting, and walking while the control group performed conventional matched exercises. Trail making test (TMT part A, B; TMT-A, TMT-B, TMT B-A), six-spot step test (SSST), and choice stepping reaction time (CSRT-including reaction time (RT), movement time (MVT), and total response time (TRT)) were assessed pre- and post-intervention (short-term), and after three-month follow-up (mid-term).

RESULTS

The intervention group showed faster TMT-B (p = 0.003) and TMT B-A (p = 0.002) at post-intervention and faster SSST at both post-intervention (p = 0.002) and follow-up (p = 0.04). The CSRT components showed no between-group differences at post-intervention; however, at follow-up, the intervention group had lower TRT (p = 0.046) and MVT (p = 0.015). TMT-A and RT had no significant between-group differences.

CONCLUSIONS

In short-term, exergames led to more improvements in complex attention, executive function, and lower-limb functional coordination comparing to the matched conventional exercises. In mid-term, exergaming was more effective for improving stepping time and lower-limb functional coordination. However, the two approaches did not show any superiority over each other for improving simple attention and RT.Implications for rehabilitationWhen designed properly, exergames have great potential to improve attention and executive function of people with multiple sclerosis (PwMS), at least in the short-term.Exergames seem like an appropriate option for improving lower limb coordination and decreasing choice stepping response time among PwMS in the mid-term.Exergames do not have superiority in improving the choice stepping reaction time compared to their matched conventional treatment.

A proposed new taxonomy of cognitive phenotypes in multiple sclerosis: The International Classification of Cognitive Disorders in MS (IC-CoDiMS)

BACKGROUND

Characterization of cognitive impairment (CI) in multiple sclerosis into distinct phenotypes holds promise for individualized treatments and biomarker exploration.

OBJECTIVE

Apply a previously validated, neuropsychologically driven diagnostic algorithm to identify a taxonomy of the type of cognitive phenotypes in multiple sclerosis.

METHODS

An algorithm developed and validated in other neurological diseases was applied to a cohort of 1281 people with multiple sclerosis who underwent clinical neuropsychological evaluation across three multiple sclerosis centers. A domain was marked impaired if scores on two tests within the domain fell below one of the two thresholds of interest (compared to controls; -1.0 SD and -1.5 SD below the mean). Results were then tabulated for each participant to determine the type of impairments across the sample.

RESULTS

At -1 SD threshold, 48.7% were intact, 21.6% had single-domain, 14.3% bi-domain, and 15.4% multi-domain impairment. At -1.5 SD threshold, 72.9% were intact, 14.0% had single-domain, 8.2% bi-domain, and 5.0% multi-domain impairment. Processing speed was the most frequent single-domain impairment, followed by executive function and memory.

CONCLUSIONS

These findings advance the taxonomy of cognitive phenotypes in multiple sclerosis and clarify the type and distribution of possible cognitive diagnoses, pave the way for further investigation of associated biomarkers, and provide clinically meaningful information to guide individualized treatment and rehabilitation.

Multi-Disease Validation of the RUDAS for Cognitive Screening in Alzheimer's Disease, Parkinson's Disease, and Multiple Sclerosis

BACKGROUND

The Rowland Universal Dementia Assessment Scale (RUDAS) is a cognitive test with favorable diagnostic properties for detecting dementia and a low influence of education and cultural biases.

OBJECTIVE

We aimed to validate the RUDAS in people with Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS).

METHODS

We enrolled one hundred and fifty participants (60 with AD, 30 with PD, 60 with MS, and 120 healthy controls (HC)). All clinical groups completed a comprehensive neuropsychological battery, RUDAS, and standard cognitive tests of each disorder: MMSE, SCOPA-COG, and Symbol Digit Modalities Test. Intergroup comparisons between clinical groups and HC and ROC curves were estimated. Random Forest algorithms were trained and validated to detect cognitive impairment using RUDAS and rank the most relevant scores.

RESULTS

The RUDAS scores were lower in patients with AD, and patients with PD and MS showed cognitive impairment compared to healthy controls. Effect sizes were generally large. The total score was the most discriminative, followed by the memory score. Correlations with standardized neuropsychological tests were moderate to high. Random Forest algorithms obtained accuracies over 80-90% using the RUDAS for diagnosing AD and cognitive impairment associated with PD and MS.

CONCLUSION

Our results suggest the RUDAS is a valid test candidate for multi-disease cognitive screening tool in AD, PD, and MS.

Validation of the Norma Latina Neuropsychological Assessment Battery in Patients with Alzheimer's Disease in Mexico

To our knowledge, this is the first study reported in the literature that has validated the Norma Latina Battery in a population of people with Alzheimer's disease (AD) in Mexico. The objective of the study was to determine the discriminant validity of the Norma Latina Battery in a group of Mexican individuals with AD and a group of heathy controls (HC). The Norma Latina Battery was administered to 234 Mexican participants (117 HC and 117 individuals with AD). Results show that: (1) the Norma Latina Battery has high discriminative capacity between groups in all domains; (2) participants with AD presented worse scores in each of the cognitive domains compared to the HC and a greater number of low scores in each of the established thresholds or cut-off points; and finally, (3) the Norma Latina Battery had optimal sensitivity and specificity, especially when a set was observed ≥5 scores below the 10th percentile or ≥4 scores below the 5th percentile. In conclusion, it is recommended that both clinicians and researchers use this battery in the evaluation of Mexican people with AD to better understand the prognosis of the disease and its subsequent treatment.

Quantifying and Reporting Outcomes in Pediatric Epilepsy Surgery: A Systematic Review

OBJECTIVE

Several instruments and outcomes measures have been reported in pediatric patients undergoing epilepsy surgery. The objective of this systematic review is to summarize, evaluate, and quantify outcome metrics for the surgical treatment of pediatric epilepsy that address seizure frequency, neuropsychological, and health-related quality of life (HRQL).

METHODS

We performed a systematic review according to PRISMA guidelines to identify publications between 2010 and June 2021 from PubMed, Embase, and the Cochrane Database of Systematic Reviews that report clinical outcomes in pediatric epilepsy surgery.

RESULTS

Eighty-one papers were included for review. Overall, rates of post-operative seizure frequency were the most common metric reported (n= 78 studies, 96%). Among the seizure frequency metrics, the Engel Epilepsy Surgery Outcome Scale (n= 48 studies, 59%) was most commonly reported. Neuropsychological outcomes, performed in 32 studies (40%) were assessed using 36 different named metrics. Health-Related Quality of Life (HRQL) outcomes were performed in 16 studies (20%) using 13 different metrics. Forty-six studies (57%) reported postoperative changes in anti-epileptic drug (AED) regimen and time-to-event analysis was performed in 15 (19%) studies. Only 13 outcomes metrics (1/5 seizure frequency, 6/13 HRQL, 6/36 neuropsychological) have been validated for use in pediatric patients with epilepsy and only 13 have been assessed through reliability studies (4/5 seizure frequency, 6/13 HRQL, and 3/36 neuropsychological). Of the 81 included studies, 17 (21%) used at least one validated metric.

SIGNIFICANCE

Outcome variable metrics in pediatric epilepsy surgery are highly variable. While nearly all studies report seizure frequency, there is considerable variation in reporting. HRQL and neuropsychological outcomes are less frequently and much more heterogeneously reported. Reliable and validated outcomes metrics should be used to increase standardization and accuracy of reporting outcomes in pediatric patients undergoing epilepsy surgery.

Cognitive dysfunction associated with COVID-19: A comprehensive neuropsychological study

OBJECTIVE

Recent evidence suggests that patients suffering post-acute COVID syndrome frequently report cognitive complaints, but their characteristics and pathophysiology are unknown. This study aims to determine the characteristics of cognitive dysfunction in patients reporting cognitive complaints after COVID-19 and to evaluate the correlation between cognitive function and anxiety, depression, sleep, and olfactory function.

METHODS

Cross-sectional study involving 50 patients with COVID-19 reporting cognitive complaints 9.12 ± 3.46 months after the acute infection. Patients were evaluated with a comprehensive neuropsychological protocol, and scales of fatigue, depression, anxiety, sleep and an olfactory test. Normative data and an age- and education matched healthy control group were used for comparison.

RESULTS

COVID-19 patients showed a diminished performance on several tests evaluating attention and executive function, with alterations in processing speed, divided attention, selective attention, visual vigilance, intrinsic alertness, working memory, and inhibition; episodic memory; and visuospatial processing. Cognitive performance was correlated with olfactory dysfunction, and sleep quality and anxiety to a lesser extent, but not depression.

CONCLUSIONS

Patients with COVID-19 reporting cognitive symptoms showed a reduced cognitive performance, especially in the attention-concentration and executive functioning, episodic memory, and visuospatial processing domains. Future studies are necessary to disentangle the specific mechanisms associated with COVID-19 cognitive dysfunction.

Validation of two new scales for the assessment of fatigue in Multiple Sclerosis: F-2-MS and FACIT-F

BACKGROUND

Fatigue is one of the most common symptoms in neurology, especially in MS patients with a prevalence of 65%. It is described as the most disabling symptom by 40% of MS patients. This study aimed to validate the Functional Assessment of Chronic Illness Therapy fatigue version (FACIT-F) and the F-2-MS scale, a new tool to distinguish between fatigue and fatigability.

METHODS

One hundred and fifteen patients with relapsing-remitting MS were enrolled. All patients completed a comprehensive neuropsychological battery, previously validated in MS. Fatigue was evaluated using the Fatigue Severity Scale (FSS), the Modified version of the Fatigue Impact Scale (MFIS), the Functional Assessment of Chronic Illness Therapy measure system (fatigue version) (FCIT-F), and a new tool for the assessment of fatigue and fatigability: the F-2-MS scale. Internal consistency was estimated with Cronbach's Alpha. For intergroup comparisons, Student's t-test and Pearson's chi-squared test were used. Pearson's correlation test was calculated for quantitative variables. Cohen's d was calculated to evaluate the effect size. Binary logistic regression was performed, considering the presence of fatigue as a criterion variable, and the FACIT-F and F-2-MS scores were added as predictor variables. ROC curves were also estimated. We conducted a confirmatory factor analysis for the F-2-MS scale, considering two latent factors.

RESULTS

FACIT-F and F-2-MS showed high internal consistency. Both scales were highly correlated with MFIS and FSS, and showed a low correlation with Symbol Digit Modalities Test. There were significant differences between fatigued and non-fatigued patients on FACIT-F and F-2-MS scores with large effect sizes. Both scales showed AUC > 0.90 and achieved a correct classification >87%. Confirmatory factor analysis showed moderate evidence of two dimensions on the F-2-MS scale.

CONCLUSIONS

The FACIT-F and F-2-MS scales showed appropriated psychometric properties to be used as fatigue measures in clinical and research settings, allowing a correct distinction between patients with and without fatigue, and contributing to the understanding of the complexities of fatigue in MS.

Development, Spanish Normative Data, and Validation of a Social Cognition Battery in Prodromal Alzheimer's Disease and Multiple Sclerosis

OBJECTIVES

The assessment of social cognition changes may be challenging, especially in the earliest stages of some neurodegenerative diseases. Our objective was to validate a social cognition battery from a multidomain perspective. In this regard, we aimed to adapt several tests, collect normative data, and validate them in prodromal Alzheimer's disease (AD) and multiple sclerosis (MS).

METHODS

A total of 92 healthy controls, 25 prodromal AD, and 39 MS patients were enrolled. Age-, gender-, and education-matched control groups were created for comparisons. Social cognition battery was composed of an emotion-labeling task developed from FACES database, the Story-based Empathy test (SET), the Faux Pas test, and the Interpersonal Reactivity Index. Patients were also evaluated with a comprehensive cognitive battery to evaluate the other cognitive domains. Automatic linear modeling was used to predict each social cognition test's performance using the neuropsychological tests examining other cognitive domains.

RESULTS

The reliability of the battery was moderate-high. Significant intergroup differences were found with medium-large effect sizes. Moderate correlations were found between social cognition battery and neuropsychological tests. The emotion labeling task and SET showed moderate correlations with age and education, and age, respectively. Regression-based norms were created considering the relevant demographic variables. Linear regression models including other neuropsychological tests explained between 7.7% and 68.8% of the variance of the social cognition tests performance.

CONCLUSIONS

Our study provides a battery for the assessment of social cognition in prodromal AD and MS with Spanish normative data to improve the evaluation in clinical and research settings.

Cognitive Processes Underlying Verbal Fluency in Multiple Sclerosis

Background: Verbal fluency (VF) has been associated with several cognitive functions, but the cognitive processes underlying verbal fluency deficits in Multiple Sclerosis (MS) are controversial. Further knowledge about VF could be useful in clinical practice, because these tasks are brief, applicable, and reliable in MS patients. In this study, we aimed to evaluate the cognitive processes related to VF and to develop machine-learning algorithms to predict those patients with cognitive deficits using only VF-derived scores.

Methods: Two hundred participants with MS were enrolled and examined using a comprehensive neuropsychological battery, including semantic and phonemic fluencies. Automatic linear modeling was used to identify the neuropsychological test predictors of VF scores. Furthermore, machine-learning algorithms (support vector machines, random forest) were developed to predict those patients with cognitive deficits using only VF-derived scores.

Results: Neuropsychological tests associated with attention-executive functioning, memory, and language were the main predictors of the different fluency scores. However, the importance of memory was greater in semantic fluency and clustering scores, and executive functioning in phonemic fluency and switching. Machine learning algorithms predicted general cognitive impairment and executive dysfunction, with F1-scores over 67–71%.

Conclusions: VF was influenced by many other cognitive processes, mainly including attention-executive functioning, episodic memory, and language. Semantic fluency and clustering were more explained by memory function, while phonemic fluency and switching were more related to executive functioning. Our study supports that the multiple cognitive components underlying VF tasks in MS could serve for screening purposes and the detection of executive dysfunction.