Italian normative data for a stroke specific cognitive screening tool: the Oxford Cognitive Screen (OCS)

The Korean Version of the Oxford Cognitive Screen (K-OCS) Normative Study

OBJECTIVE

To generate a Korean version of the Oxford Cognitive Screen (K-OCS) and obtain cutoff scores that determine the impairment of each subdomain. Post-stroke cognitive impairment (PSCI) negatively impacts the rehabilitation process and independence in daily life. Its obscure manifestations require effective screening for appropriate rehabilitation. However, in most rehabilitation clinics, psychological evaluation tools for Alzheimer's dementia have been used without such considerations. The OCS is a screening assessment tool for PSCI and vascular dementia that can evaluate the cognitive domains most often affected by stroke, including language, attention, memory, praxis, and numerical cognition. It comprises 10 subtasks and enables quick and effective cognitive evaluation.

METHODS

The K-OCS, which considers Korea's unique cultural and linguistic characteristics, was developed with the approval and cooperation of the original author. Enrollment of participants without disabilities was announced at Duksung Women's University, Yongin Sevrance Hospital, CHA Bundang Medical Center. The study was conducted between September 2020 and March 2022 on 97 male and female participants aged ≥30 years.

RESULTS

All the 97 participants completed the task. In this study, the 5th percentile score was presumed to be the cutoff value for each score, and the values are provided here. The cutoff score for each OCS subtask was similar to that of the original British version.

CONCLUSION

We suggest the usability of the K-OCS as a screening tool for PSCI by providing the cutoff value of each subtask.

Effects of Virtual Reality Cognitive Training on Neuroplasticity: A Quasi-Randomized Clinical Trial in Patients with Stroke

Cognitive Rehabilitation (CR) is a therapeutic approach designed to improve cognitive functioning after a brain injury, including stroke. Two major categories of techniques, namely traditional and advanced (including virtual reality-VR), are widely used in CR for patients with various neurological disorders. More objective outcome measures are needed to better investigate cognitive recovery after a stroke. In the last ten years, the application of electroencephalography (EEG) as a non-invasive and portable neuroimaging method has been explored to extract the hallmarks of neuroplasticity induced by VR rehabilitation approaches, particularly within the chronic stroke population. The aim of this study is to investigate the neurophysiological effects of CR conducted in a virtual environment using the VRRS device. Thirty patients with moderate-to-severe ischemic stroke in the chronic phase (at least 6 months after the event), with a mean age of 58.13 (±8.33) for the experimental group and 57.33 (±11.06) for the control group, were enrolled. They were divided into two groups: an experimental group and a control group, receiving neurocognitive stimulation using VR and the same amount of conventional neurorehabilitation, respectively. To study neuroplasticity changes after the training, we focused on the power band spectra of theta, alpha, and beta EEG rhythms in both groups. We observed that when VR technology was employed to amplify the effects of treatments on cognitive recovery, significant EEG-related neural improvements were detected in the primary motor circuit in terms of power spectral density and time-frequency domains. Indeed, EEG analysis suggested that VR resulted in a significant increase in both the alpha band power in the occipital areas and the beta band power in the frontal areas, while no significant variations were observed in the theta band power. Our data suggest the potential effectiveness of a VR-based rehabilitation approach in promoting neuroplastic changes even in the chronic phase of ischemic stroke.

Prediction of rehabilitation induced motor recovery after stroke using a multi-dimensional and multi-modal approach

Background

Stroke is a debilitating disease affecting millions of people worldwide. Despite the survival rate has significantly increased over the years, many stroke survivors are left with severe impairments impacting their quality of life. Rehabilitation programs have proved to be successful in improving the recovery process. However, a reliable model of sensorimotor recovery and a clear identification of predictive markers of rehabilitation-induced recovery are still needed. This article introduces the cross-modality protocols designed to investigate the rehabilitation treatment's effect in a group of stroke survivors.

Methods/design

A total of 75 stroke patients, admitted at the IRCCS San Camillo rehabilitation Hospital in Venice (Italy), will be included in this study. Here, we describe the rehabilitation programs, clinical, neuropsychological, and physiological/imaging [including electroencephalography (EEG), transcranial magnetic stimulation (TMS), and magnetic resonance imaging (MRI) techniques] protocols set up for this study. Blood collection for the characterization of predictive biological biomarkers will also be taken. Measures derived from data acquired will be used as candidate predictors of motor recovery.

Discussion/summary

The integration of cutting-edge physiological and imaging techniques, with clinical and cognitive assessment, dose of rehabilitation and biological variables will provide a unique opportunity to define a predictive model of recovery in stroke patients. Taken together, the data acquired in this project will help to define a model of rehabilitation induced sensorimotor recovery, with the final aim of developing personalized treatments promoting the greatest chance of recovery of the compromised functions.

The Oxford Cognitive Screen for use with Australian people after stroke (OCS-AU): The adaptation process and determining cut scores for cognitive impairment using a cross-sectional normative study

INTRODUCTION

Two parallel versions (A and B) of the Oxford Cognitive Screen (OCS) were developed in the United Kingdom (UK) as a stroke-specific screen of five key cognitive domains commonly affected post-stroke. We aimed to develop the Australian versions A and B (OCS-AU), including Australian cut-scores indicative of impairment. We hypothesised there to be no difference in performance between the UK and Australian normative data cohorts.

METHODS

Our multidisciplinary expert panel used the UK pre-defined process to develop the OCS-AU versions A and B. We then conducted a cross-sectional normative study. We purposively recruited community-dwelling, Australian-born, and educated adults; with no known cognitive impairment; representative of age, sex, education level, and living location; at seven sites (four metropolitan, three regional) across four Australian states. Participants completed one or both OCS-AU versions in a randomised order. Australian cohorts were compared with the corresponding UK cohorts for demographics using Pearson's chi-squared test for sex and education, and Welch two-sample t test for age. For the cut-scores indicating cognitive impairment, the fifth (95th) percentiles and group mean performance score for each scored item were compared using Welch two-sample t tests. The pre-defined criteria for retaining OCS cut-scores had no statistically significant difference in either percentile or group mean scores for each scored item.

RESULTS

Participants (n = 83) were recruited: fifty-eight completed version A [age (years) mean = 61,SD = 15; 62% female], 60 completed version B [age (years) mean = 62,SD = 13, 53% female], and 35 completed both [age (years) mean = 64,SD = 11, 54% female]. Education was different between the cohorts for version B (12 years, p = 0.002). Cut-scores for all 16 scored items for the OCS-AU version B and 15/16 for version A met our pre-defined criteria for retaining the OCS cut scores.

CONCLUSIONS

The OCS-AU provides clinicians with an Australian-specific, first-line cognitive screening tool for people after stroke. Early screening can guide treatment and management.

Cognitive reserve index and long-term disability in patients with severe traumatic brain injury discharged from the intensive rehabilitation unit

Objectives

The "cognitive reserve" (CR) theory posits that higher premorbid cognitive activities can mitigate the effects of brain damage. This study aimed to investigate the association between CR and long-term functional autonomy in patients surviving a severe traumatic brain injury (sTBI).

Setting

Data were collected from the database of inpatients with severe acquired brain injury in a rehabilitation unit admitted from August 2012 to May 2020.

Participants

Patients that had incurred an sTBI, aged 18+ years, completing the phone Glasgow Outcome Scale-Expanded at follow-up (pGOS-E) in absence of previous brain trauma or neurological disease, or cognitive disorders were included. Patients with severe brain injury from non-traumatic etiologies were not included in the study.

Design

In this longitudinal study, all patients underwent a multidimensional assessment including the cognitive reserve index questionnaire (CRIq), the coma recovery scale-revised, the level of cognitive functioning, the Disability Rating Scale (DRS), and the Galveston Orientation and Amnesia Test at admission. At discharge, functional scales were administered again together with the Glasgow Outcome Scale. The pGOS-E was assessed at follow-up.

Main measures

pGOS-E.

Results

A total of 106 patients/caregivers underwent the pGOS-E after 5.8 [3.6] years from the event. Among them, 46 (43.4%) died after discharge, and 60 patients [men: 48 (80%); median age: 54 years; median time post-onset: 37 days; median education level: 10 years; median CRIq total score: 91] were included in the analysis exploring the association between pGOS-E and demographic data, cognitive reserve surrogates, and clinical variables at admission and discharge from the rehabilitation unit. A younger age (B = -0.035, p = 0.004) and a lower DRS category at discharge (B = -0.392, p = 0.029) were significantly related to a higher long-term functional autonomy in the multivariate analysis.

Conclusion

Long-term functional autonomy was not influenced by CR as assessed through the educational level and the CRIq.

Extra-Linguistic Cognitive Functions Involved in the Token Test: Results from a Cohort of Non-Aphasic Stroke Patients with Right Hemisphere Lesion

BACKGROUND

The Token Test (TT) is widely used to examine comprehension disorders in aphasic patients, but abilities other than language may affect a patient's performance. This study aims to explore the correlation between the TT subtest performances and the performances in extra-linguistic cognitive areas in a cohort of patients from the Intensive Rehabilitation Post-Stroke (RIPS) study with a first, right hemisphere stroke and without aphasia, prospectively enrolled at admission to intensive inpatient post-acute rehabilitation.

METHODS

The patients were administered the TT (50-item version), the forward and backward digit span (DST), and the Montreal Cognitive Assessment (MoCA). Spearman's partial correlations adjusted by age were used to evaluate the association between the number of errors in the TT and the other tests' corrected scores.

RESULTS

Of the 37 patients enrolled in this study, 29.7% made 3-11 errors on the TT, 27.0% more than 11 errors, mostly in parts IV and V. The forward and backward digit span scores showed correlations with errors in part V of the TT (r = -0.408, p = 0.013; r = -0.307, p = 0.027). The errors in part IV of the TT presented a correlation with a forward digit span too (r = -0.394, p = 0.017). With respect to MoCA domains, executive functioning, and orientation were related to the TT part V errors (r = -0.468, p = 0.007; r = -0.499, p = 0.003). The orientation also correlated with the TT part III (r = -0.504, p = 0.002).

CONCLUSION

Our findings show that the TT performances in patients with right hemisphere stroke and without aphasia are related to impairments in auditory-verbal span/auditory working memory mostly for TT scores on subpart V as measured by the DST and to executive function and orientation, as measured by the MoCA subtests.

Validity evidence for the Cognitive Screening Test in Stroke Patients

Abstract Cognitive deficits are common among post-stroke patients. Cognitive impairments of this sort are mediated by age and education. In Brazil, the only specific cognitive screening tool designed for post-stroke patients is the Cognitive Screening Test (Triagem Cognitiva - TRIACOG). The goal of this study was to investigate validity evidence related to external variables for the TRIACOG. Our sample included 153 adults and elderly people (M = 60.08, SD = 9.61) from Porto Alegre and metropolitan area, comprising 87 post-stroke patients and 66 healthy individuals. Three-way ANOVAs were used to assess main effects and interactions between the variables group (clinical/control), age and education. An influence of group and age on scores in the TRIACOG was found. We emphasize the relevance of these results to the selection of cut-off points for the tasks and cognitive functions assessed by the instrument, considering education and age, so as to allow more accurate identification of deficits in post-stroke patients.

The Prognostic Value of Domain-Specific Cognitive Abilities Assessed by Chinese Version of Oxford Cognitive Screen on Determining ADLs Recovery in Patients with Post-Stroke Cognitive Impairment

Background

Poststroke cognitive impairment (PSCI) has been increasingly recognized in patients. However, it remains unclear whether ADLs recovery is more susceptible to domain-specific cognitive abilities after a stroke. Therefore, the study was designed to investigate the cognitive functions of patients with PSCI at admission by using the Chinese (Putonghua) Version of the Oxford Cognitive Screen (OCS-P) as well as to identify the prognostic value of domain-specific cognitive abilities on the recovery of ADLs when discharged.

Methods

A total of 153 hospitalized stroke patients were included in this prospective study. Cognitive function was assessed by OCS-P when participants were admitted to the hospital. The ADLs were measured at admission and discharge, and recovery was estimated by the improvement between admission and discharge. A diagnostic model using logistic regression was constructed to identify the prognostic value of domain-specific cognitive abilities for ADLs. The efficacy and accuracy of the diagnostic model were assessed by receiver operating characteristic (ROC) and Hosmer-Lemeshow's goodness of fit test. The diagnostic model was validated by 10-fold cross-validation and presented as a nomogram.

Results

The score of OCS-P was 60(49.75, 69). The most frequently impaired cognitive domain was number writing (60.8%), followed by verbal memory (52.9%). Multivariate logistic regression showed executive dysfunction was a risk prognostic factor of ADLs recovery (P < 0.001, OR = 3.176 [95% CI, 1.218∼8.278]). The ROC curve of the diagnostic model was 0.839, with a good diagnostic efficacy. Hosmer–Lemeshow test showed diagnostic model had good calibration ability (χ² = 8.939.3, P=0.347 > 0.05). The average error rate after adjustment of 10-fold cross-validation was 20.93%, within the acceptable range.

Conclusions

Post-stroke patients generally suffered from multidimensional cognitive impairments. Executive dysfunction screened with OCS-P at clinical admission was a reliable and accessible predictive factor ADLs recovery in patients with PSCI. Early targeted rehabilitation programs are suggested to make them as earlier as possible, especially for those having executive dysfunction while hospitalized.

The Impact of Visual Impairment on Completion of Cognitive Screening Assessments: A Post-Hoc Analysis from the IVIS Study

Aim:

The aim of this study was to evaluate completed cognitive screens in stroke survivors with and without visual impairment to explore whether the presence of visual impairment impacts on completion of cognitive screening.

Materials and methods:

Cognitive screening assessment was undertaken using the Oxford Cognitive Screen (OCS). Data from visual function assessments (inclusive of visual acuity, visual fields, eye movements and visual perception evaluation) were analysed to determine whether presence and/or type of visual impairment impacted on cognitive screening scores achieved. Covariates, including glasses use, gender, age at stroke onset and stroke type, were used to assess confounding impacts on scores attained during cognitive screening.

Results:

1500 stroke admissions were recruited. One hundred ninety-seven who completed the OCS, were identified from the IVIS study database. Those who reported visual symptoms performed worse statistically on all cognitive tasks except the recall recognition (p = 0.232) and executive tasks (p = 0.967). Visual symptoms did not prevent participants from completing every section of the OCS (p = 0.095). In certain tasks, those not wearing their required glasses performed worse, including the executive function (p = 0.012), broken hearts and sentence reading tasks.

Conclusions:

Many tasks within cognitive screening assessment are impacted by presence of visual deficits, and adjustments, where possible (e.g. good lighting, large print) should be used to facilitate completion of cognitive screening. It is important to ensure required reading correction is worn during screening.

Principal Component Analysis of Oxford Cognitive Screen in Patients With Stroke

Cognitive deficits occur in most patients with stroke and are the important predictors of adverse long-term outcome. Early identification is fundamental to plan the most appropriate care, including rehabilitation and discharge decisions. The Oxford Cognitive Screen (OCS) is a simple, valid, and reliable tool for the assessment of cognitive deficits in patients with stroke. It contains 10 subtests, providing 14 scores referring to 5 theoretically derived cognitive domains: attention, language, number, praxis, and memory. However, an empirical verification of the domain composition of the OCS subtests in stroke data is still lacking in the literature. A principal component analysis (PCA) was performed on 1,973 patients with stroke who were enrolled in OCS studies in the UK and in Italy. A number of six main components were identified relating to the domains of language and arithmetic, memory, visuomotor ability, orientation, spatial exploration, and executive functions. Bootstrapped split-half reliability analysis on patients and comparison between patients and 498 healthy participants, as that between patients with left and right hemisphere damage, confirmed the results obtained by the principal component analysis. A clarification about the contribution of each score to the theoretical original domains and to the components identified by the PCA is provided with the aim to foster the usability of OCS for both clinicians and researchers.

Rehabilitation of somatic sensation and related deficit of motor control by Mirror Box Therapy: a case report

Somatosensory disorders are often present after cerebral stroke. These deficits are associated with patients' disability. Therefore, their rehabilitation takes an importance in recovery program. However, the treatment of sensation remains poorly considered during neurorehabilitation and evidence for active sensory training is limited. Mirror Box Therapy is a simple training used to treat upper extremity motor deficits and pain also in patients with stroke. However, the effects of Mirror Box Therapy on somatosensory impairments in post-stroke patients are not deeply investigated and often exclusively motor exercises are provided during therapy.The aim of the present study was to investigate the effects of Mirror Box Therapy sensory training on somatosensory deficits in a stroke patient presenting upper limb impairment.The patient underwent to four weeks of training, five days a week. Before, during and after the Mirror Box Therapy treatment, the patient was assessed by Rivermead Assessment of Somatosensory Performance. Before and after training also upper limb motor function and performance in activities of daily living were assessed.After training patient showed an improvement in somatosensory performance. The gain was maintained at follow-up.This case report shows the effects of Mirror Box Therapy sensory training on the upper extremity for the improvement of sensation and movement in a patient with a thalamo-capsular hemorrhagic stroke during the subacute phase.

Critical issue on the extinction and inattention subtest of NIHSS scale: an analysis on post-acute stroke patients attending inpatient rehabilitation

Objectives

This study aims to evaluate the diagnostic performance of NIHSS extinction and inattention item, compared to the results of the Oxford Cognitive Screen (OCS) heart subtest. Additionally, the possible role of the NIHSS visual field subtest on the NIHSS extinction and inattention subtest performance is explored and discussed.

Methods

We analysed scores on NIHSS extinction and inattention subtest, NIHSS visual field subtest, and OCS heart subtest on a sample of 118 post-stroke patients.

Results

Compared to OCS heart subtest, the results on NIHSS extinction and inattention subtest showed an accuracy of 72.9% and a moderate agreement level (Cohen’s kappa = 0.404). Furthermore, a decrease in NIHSS accuracy detecting neglect (61.1%) was observed in patients with pathological scores in NIHSS visual field item.

Conclusions

Extreme caution is recommended for the diagnostic performance of extinction and inattention item of NIHSS. Signs of neglect may not be detected by NIHSS, and may be confused with visual field impairment.

Trial registration

This study refers to an observational study protocol submitted to ClinicalTrials.gov with identifier: NCT03968627. The name of the registry is “Development of a National Protocol for Stroke Rehabilitation in a Multicenter Italian Institution” and the date of the registration is the 30th May 2019.

Psychometrics and diagnostics of Italian cognitive screening tests: a systematic review

BACKGROUND

Cognitive screening tests (CSTs) are crucial to neuropsychological diagnostics, and thus need to be featured by robust psychometric and diagnostic properties. However, CSTs happen not to meet desirable statistical standards, negatively affecting their level of recommendations and applicability. This study aimed at (a) providing an up-to-date compendium of available CSTs in Italy, (b) report their psychometric and diagnostic properties, and (c) address related limitations.

METHODS

This review was implemented by consulting Preferred Reporting Items for Systematic Reviews and Meta-Analyses and pre-registered on the International Prospective Register of Systematic Reviews. Standardization and usability studies focusing on norms, validity, reliability, or sensitivity/specificity (and derived metrics) in adults were considered for eligibility. Quality assessment was performed by means of an ad hoc checklist collecting information on sampling, psychometrics/diagnostics, norming, and feasibility.

RESULTS

Sixty studies were included out of an initial N = 683. Identified CSTs (N = 40) were classified into general, domain-, and disease-specific (N = 17, 7, and 16, respectively), the latter being less statistically robust than remaining categories. Validity and reliability evidence was provided for 29 and 26 CSTs, respectively, sensitivity/specificity for 20 and norms for 33. Prevalence- and post-test-based diagnostic metrics were seldomly represented; factorial structures, ceiling/floor effects, and acceptability rarely investigated; content, face, and ecological validity never assessed.

DISCUSSION

Although available Italian CSTs overall met basic psychometric/diagnostic requirements, their statistical profile often proved to be poor on several properties that are desirable for clinical applications, with a few exceptions among general and domain-specific ones.

Progressive macrographia for block letter writing: A case study

"Macrographia", a relatively rare symptom generally following cerebellar diseases, consists of an abnormally large handwriting. The case reported in the present investigation shows several outstanding features. First, it is of the progressive variety, letters increase in size as one goes through the word towards the lower-right portion of space. Moreover, it is limited to one allographic variety, that is, block letters. This phenomenon is previously unreported, all allographic varieties being usually equally affected. Finally, no prominent cerebellar or basal ganglia abnormality could be demonstrated with structural MRI or PET. From a cognitive point of view, a peculiar combination of spatial attention, executive function and working memory deficits is proposed to account for the progressive misalignment and elongation of individual letters when specifically writing in block prints. From an anatomical perspective, the pattern of multifocal lesions, encompassing multiple cortical areas in both hemispheres and the corpus callosum, may support this multi-componential interpretation of the reported phenomenon.

A low-dimensional structure of neurological impairment in stroke

Neurological deficits following stroke are traditionally described as syndromes related to damage of a specific area or vascular territory. Recent studies indicate that, at the population level, post-stroke neurological impairments cluster in three sets of correlated deficits across different behavioural domains. To examine the reproducibility and specificity of this structure, we prospectively studied first-time stroke patients (n = 237) using a bedside, clinically applicable, neuropsychological assessment and compared the behavioural and anatomical results with those obtained from a different prospective cohort studied with an extensive neuropsychological battery. The behavioural assessment at 1-week post-stroke included the Oxford Cognitive Screen and the National Institutes of Health Stroke Scale. A principal component analysis was used to reduce variables and describe behavioural variance across patients. Lesions were manually segmented on structural scans. The relationship between anatomy and behaviour was analysed using multivariate regression models. Three principal components explained ≈50% of the behavioural variance across subjects. PC1 loaded on language, calculation, praxis, right side neglect and memory deficits; PC2 loaded on left motor, visual and spatial neglect deficits; PC3 loaded on right motor deficits. These components matched those obtained with a more extensive battery. The underlying lesion anatomy was also similar. Neurological deficits following stroke are correlated in a low-dimensional structure of impairment, related neither to the damage of a specific area or vascular territory. Rather they reflect widespread network impairment caused by focal lesions. These factors showed consistency across different populations, neurobehavioural batteries and, most importantly, can be described using a combination of clinically applicable batteries (National Institutes of Health Stroke Scale and Oxford Cognitive Screen). They represent robust behavioural biomarkers for future stroke population studies.

Influence of Cognitive Impairment on the Recovery of Subjects with Subacute Stroke Undergoing Upper Limb Robotic Rehabilitation

Cognitive decline is often present in stroke survivors, with a significant impact on motor recovery. However, how specific cognitive domains could impact motor recovery after robotic rehabilitation in patients with stroke is still not well understood. In this study, we analyzed the relationship between cognitive impairment and the outcome of a robot-mediated upper limb rehabilitation intervention in a sample of 51 subacute stroke patients. Participants were enrolled and treated with a set of robotic and sensor-based devices. Before the intervention, patients underwent a cognitive assessment by means of the Oxford Cognitive Screen. To assess the effect of the 30-session rehabilitation intervention, patients were assessed twice with the following outcome measures: the Fugl-Meyer Assessment for Upper Extremity (FMA-UE), to evaluate motor function; the Upper limb Motricity Index (MI), to evaluate upper limb muscle strength; the Modified Barthel Index (mBI), to evaluate activities of daily living and mobility. We found that deficits in spatial attention and executive functions impacted the mBI improvement, while language, number processing, and spatial attention deficits reduced the gains in the FMA-UE. These results suggest the importance to evaluate the cognitive functions using an adequate tool in patients with stroke undergoing a robotic rehabilitation intervention.

Preoperative Repetitive Navigated TMS and Functional White Matter Tractography in a Bilingual Patient with a Brain Tumor in Wernike Area

Awake surgery and intraoperative neuromonitoring represent the gold standard for surgery of lesion located in language-eloquent areas of the dominant hemisphere, enabling the maximal safe resection while preserving language function. Nevertheless, this functional mapping is invasive; it can be executed only during surgery and in selected patients. Moreover, the number of neuro-oncological bilingual patients is constantly growing, and performing awake surgery in this group of patients can be difficult. In this scenario, the application of accurate, repeatable and non-invasive preoperative mapping procedures is needed, in order to define the anatomical distribution of both languages. Repetitive navigated transcranial magnetic stimulation (rnTMS) associated with functional subcortical fiber tracking (nTMS-based DTI-FT) represents a promising and comprehensive mapping tool to display language pathway and function reorganization in neurosurgical patients. Herein we report a case of a bilingual patient affected by brain tumor in the left temporal lobe, who underwent rnTMS mapping for both languages (Romanian and Italian), disclosing the true eloquence of the anterior part of the lesion in both tests. After surgery, language abilities were intact at follow-up in both languages. This case represents a preliminary application of nTMS-based DTI-FT in neurosurgery for brain tumor in eloquent areas in a bilingual patient.

Introducing the tablet-based Oxford Cognitive Screen-Plus (OCS-Plus) as an assessment tool for subtle cognitive impairments

Here, we present the Oxford Cognitive Screen-Plus, a computerised tablet-based screen designed to briefly assess domain-general cognition and provide more fine-grained measures of memory and executive function. The OCS-Plus was designed to sensitively screen for cognitive impairments and provide a differentiation between memory and executive deficits. The OCS-Plus contains 10 subtasks and requires on average 24 min to complete. In this study, 320 neurologically healthy ageing participants (age M = 62.66, SD = 13.75) from three sites completed the OCS-Plus. The convergent validity of this assessment was established in comparison to the ACE-R, CERAD and Rey–Osterrieth. Divergent validity was established through comparison with the BDI and tests measuring divergent cognitive domains. Internal consistency of each subtask was evaluated, and test–retest reliability was determined. We established the normative impairment cut-offs for each of the subtasks. Predicted convergent and divergent validity was found, high internal consistency for most measures was also found with the exception of restricted range tasks, as well as strong test–retest reliability, which provided evidence of test stability. Further research demonstrating the use and validity of the OCS-Plus in various clinical populations is required. The OCS-Plus is presented as a standardised cognitive assessment tool, normed and validated in a sample of neurologically healthy participants. The OCS-Plus will be available as an Android App and provides an automated report of domain-general cognitive impairments in executive attention and memory.

Rehabilitation and Biomarkers of Stroke Recovery: Study Protocol for a Randomized Controlled Trial

Background: Stroke is a leading cause of disability. Nonetheless, the care pathway for stroke rehabilitation takes partially into account the needs of chronic patients. This is due in part to the lack of evidence about the mechanisms of recovery after stroke, together with the poor knowledge of related and influencing factors. Here we report on the study protocol "Rehabilitation and Biomarkers of Stroke Recovery," which consists of 7 work-packages and mainly aim to investigate the effects of long-term neurorehabilitation on stroke patients and to define a related profile of (clinical-biological, imaging, neurophysiological, and genetic-molecular) biomarkers of long-term recovery after stroke. The work-package 1 will represent the main part of this protocol and aims to compare the long-term effects of intensive self-rehabilitation vs. usual (rehabilitation) care for stroke. Methods: We planned to include a total of 134 adult subacute stroke patients (no more than 3 months since onset) suffering from multidomain disability as a consequence of first-ever unilateral ischemic stroke. Eligible participants will be randomly assigned to one of the following groups: intensive self-rehabilitation (based on the principles of "Guided Self-Rehabilitation Contract") vs. usual care (routine practice). Treatment will last 1 year, and patients will be evaluated every 3 months according to their clinical presentation. The following outcomes will be considered in the main work-package: Fugl-Meyer assessment, Cognitive Oxford Screen Barthel Index, structural and functional neuroimaging, cortical excitability, and motor and somatosensory evoked potentials. Discussion: This trial will deal with the effects of an intensive self-management rehabilitation protocol and a related set of biomarkers. It will also investigate the role of training intensity on long-term recovery after stroke. In addition, it will define a set of biomarkers related to post-stroke recovery and neurorehabilitation outcome in order to detect patients with greater potential and define long-term individualized rehabilitation programs. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT04323501.

Robotic Rehabilitation: An Opportunity to Improve Cognitive Functions in Subjects With Stroke. An Explorative Study

Background: After a stroke, up to three-quarters of acute and subacute stroke survivors exhibit cognitive impairment, with a significant impact on functional recovery, quality of life, and social engagement. Robotic therapy has shown its effectiveness on motor recovery, but its effectiveness on cognitive recovery has not fully investigated. Objective: This study aims to assess the impact of a technological rehabilitation intervention on cognitive functions in patients with stroke, using a set of three robots and one sensor-based device for upper limb rehabilitation. Methods: This is a pilot study in which 51 patients were enrolled. An upper limb rehabilitation program was performed using three robots and one sensor-based device. The intervention comprised motor/cognitive exercises, especially selected among the available ones to train also cognitive functions. Patients underwent 30 rehabilitation sessions, each session lasting 45 minutes, 5 days a week. Patients were assessed before and after the treatment with several cognitive tests (Oxford Cognitive Scale, Symbol Digit Modalities Test, Digit Span, Rey-Osterrieth Complex Figure, Tower of London, and Stroop test). In addition, motor (Fugl-Meyer Assessment and Motricity Index) and disability (modified Barthel Index) scales were used. Results: According to the Oxford Cognitive Scale domains, a significant percentage of patients exhibited cognitive deficits. Excluding perception (with only one patient impaired), the domain with the lowest percentage of patients showing a pathological score was praxis (about 25%), while the highest percentage of impaired patients was found in calculation (about 70%). After the treatment, patients improved in all the investigated cognitive domains, as measured by the selected cognitive assessment scales. Moreover, motor and disability scales confirmed the efficacy of robotics on upper limb rehabilitation in patients with stroke. Conclusions: This explorative study suggests that robotic technology can be used to combine motor and cognitive exercises in a unique treatment session. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT04164381.

The Dutch version of the Oxford Cognitive Screen (OCS-NL): normative data and their association with age and socio-economic status

The Oxford Cognitive Screen (OCS) is a screening tool designed for stroke patients, assessing attention, executive functions, language, praxis, numeric cognition and memory. Here we present norms for the two parallel versions of the Dutch OCS (OCS-NL, acquired in 246 participants for version A and a subset of 179 participants for version B. We evaluated the association of age and socio-economic status (i.e. education, income, occupation) with OCS-NL performance There were no systematic performance differences between income groups, nor between manual and non-manual workers. There were small differences between education groups. The association of education and performance did not vary across subtests. The association of age and performance varied across subtests, with the strongest associations for the naming, praxis, verbal memory and executive task. Thus, OCS-NL norms do not need to be stratified on income and occupation and age-specific norms are recommended for some subtests.

A Danish version of the Oxford cognitive screen: a stroke-specific screening test as an alternative to the MoCA

Cognitive deficits are common following stroke and have many negative consequences. They must be identified to provide appropriate interventions and care. In Denmark, the Montreal Cognitive Assessment (MoCA), a dementia screening tool, is commonly used to screen for cognitive deficits following stroke, despite its limitations in this context. This study aimed to make the Oxford Cognitive Screen (OCS), a stroke-specific cognitive screening tool, available in Danish and to provide population appropriate normative data. Additionally, the study aimed to evaluate the appropriateness of the MoCA cutoff of 25/26 currently used in Denmark. A sample of healthy Danish participants aged 36-89 was assessed using the Danish OCS and MoCA. Mean performance and 5th percentile cutoffs were calculated for both tests. OCS results were similar to results from European studies. For the MoCA, 5th percentile corresponded to 22.35, suggesting that the cutoff currently used in Denmark is inappropriate.

Oxford Cognitive Screen - Brazilian Portuguese version (OCS-Br) A pilot study

Cognitive impairment is very common in stroke patients and underdiagnosed. Symptoms such as language, praxis, visuospatial, visuoconstructive and memory impairment are prominent. The screening cognitive tests available do not address some specific characteristics of stroke patients and have major limitations in relation to the most impaired cognitive domains.

Psychometric Properties of the Chinese (Putonghua) Version of the Oxford Cognitive Screen (OCS-P) in Subacute Poststroke Patients without Neglect

Background

Oxford Cognitive Screen is designed for assessing cognitive functions of poststroke patients. This study was aimed to assess the psychometric properties of the Chinese (Putonghua) version of the Oxford Cognitive Screen-Putonghua (OCS-P) for use among poststroke patients without neglect.

Methods

Expert review panel evaluated content validity of the Chinese-translated items. After pilot tested the translated items, the patients and healthy participants completed the OCS-P as well as the Montreal Cognitive Assessment (MoCA-ChiB) and Goldenberg's test. A group of patients completed OCS-P for the second time within seven days. Data analyses included confirmatory factor analysis, item difficulty and item-total correlation, inter- and intrarater reliability, internal consistency, and between-group discrimination.

Results

One hundred patients and 120 younger (n = 60) or older (n = 60) healthy participants completed all the tests. Modifications were required for items in the “Picture Naming”, “Orientation”, and “Sentence Reading” subscales. Confirmatory factor analysis revealed a three-factor structure for the OCS-P subscales. The internal consistency coefficients for the three identified test dimensions were 0.30 to 0.52 (Cronbach's alpha). Construct validity coefficients between the OCS-P and MoCA-ChiB subscales were 0.45 < r < 0.79 (p < 0.001) and the “Praxis” subscale of OCS-P and Goldenberg's test was r = 0.72 (p < 0.001). The interrater reliability coefficients for the subscales were in general higher than the intrarater reliability coefficients. The “Picture Naming” and “Numerical Cognition” subscales were the most significant (p = 0.003) for differentiating patient participants from their older healthy counterpart.

Conclusion

This study generated satisfactory evidence on the content validity, substantive validity, construct validity, inter- and intrarater reliability, and known-group discrimination of the OCS-P. They support its application among poststroke patients who speak Putonghua. Future studies could review the existing five-dimension domains for improving its structural validity and internal consistency as well as generate evidence of the OCS-P for use among the poststroke patients with neglect.

Using the Oxford Cognitive Screen to Detect Cognitive Impairment in Stroke Patients: A Comparison with the Mini-Mental State Examination

Background

The Oxford Cognitive Screen (OCS) was recently developed with the aim of describing the cognitive deficits after stroke. The scale consists of 10 tasks encompassing five cognitive domains: attention and executive function, language, memory, number processing, and praxis. OCS was devised to be inclusive and un-confounded by aphasia and neglect. As such, it may have a greater potential to be informative on stroke cognitive deficits of widely used instruments, such as the Mini-Mental State Examination (MMSE) or the Montreal Cognitive Assessment, which were originally devised for demented patients.

Objective

The present study compared the OCS with the MMSE with regards to their ability to detect cognitive impairments post-stroke. We further aimed to examine performance on the OCS as a function of subtypes of cerebral infarction and clinical severity.

Methods

325 first stroke patients were consecutively enrolled in the study over a 9-month period. The OCS and MMSE, as well as the Bamford classification and NIHSS, were given according to standard procedures.

Results

About a third of patients (35.3%) had a performance lower than the cutoff (<22) on the MMSE, whereas 91.6% were impaired in at least one OCS domain, indicating higher incidences of impairment for the OCS. More than 80% of patients showed an impairment in two or more cognitive domains of the OCS. Using the MMSE as a standard of clinical practice, the comparative sensitivity of OCS was 100%. Out of the 208 patients with normal MMSE performance 180 showed impaired performance in at least one domain of the OCS. The discrepancy between OCS and MMSE was particularly strong for patients with milder strokes. As for subtypes of cerebral infarction, fewer patients demonstrated widespread impairments in the OCS in the Posterior Circulation Infarcts category than in the other categories.

Conclusion

Overall, the results showed a much higher incidence of cognitive impairment with the OCS than with the MMSE and demonstrated no false negatives for OCS vs MMSE. It is concluded that OCS is a sensitive screen tool for cognitive deficits after stroke. In particular, the OCS detects high incidences of stroke-specific cognitive impairments, not detected by the MMSE, demonstrating the importance of cognitive profiling.