Cognitive performance after ischaemic stroke

Physical Activity Behavior and Its Association With Global Cognitive Function Three Months After Stroke: The Nor-COAST Study†

OBJECTIVE

The purposes of this study were to determine the association between physical activity (PA) behavior and global cognitive function 3 months after stroke and to explore the role of physical capacity as a mediating factor.

METHODS

Participants with stroke were successively recruited at 5 different hospitals in Norway. PA was measured using accelerometers, with a follow-up period of 7 consecutive days, and global cognitive function was assessed using the Montreal Cognitive Assessment (MoCA). The general pattern of PA and the percentage of participants adhering to World Health Organization PA recommendations (at least 150 minutes of moderate-intensity aerobic PA per week) were investigated using descriptive statistics. Multiple regression and mediator analyses were used to examine the relationship between PA behavior and MoCA scores; physical capacity, measured with the Short Physical Performance Battery, served as the mediating variable.

RESULTS

A total of 193 women (42.6%) and 260 men (57.4%) with a median age of 73.7 years (25th and 75th percentiles = 65.8 and 80.4, respectively) and a median MoCA score of 25 points (25th and 75th percentiles = 22 and 27, respectively) were included. Mean total time spent walking at moderate intensity was 251.7 (SD = 164.6) min/wk (mean bout length = 20.9 [SD = 7.3] seconds), which indicated 69.3% adherence to World Health Organization guidelines. With each point decrease in the MoCA score, there was an expected 8.6% increase in the odds of nonadherence to PA recommendations. Physical capacity was identified as an important mediating factor, explaining the strength of the association between cognition and PA behavior.

CONCLUSIONS

In contrast to previous research, in the present study, most participants adhered to the updated global PA guidelines. However, people who had survived stroke and had reduced cognitive function were at higher risk of inactivity, an association mediated by physical capacity.

IMPACT

A better understanding of the association between cognition and PA behavior after stroke might help for developing more targeted early-onset interventions.

Attention-deficit/hyperactivity disorder and ischemic stroke: A Mendelian randomization study

BACKGROUND

Observational studies have found an association between attention-deficit/hyperactivity disorder (ADHD) and ischemic stroke.

AIMS

The purpose of this study was to investigate whether genetic liability to ADHD has a causal effect on ischemic stroke and its subtypes.

METHODS

In this two-sample Mendelian randomization (MR) study, genetic variants (nine single-nucleotide polymorphisms; P < 5 × 10^-8) using as instrumental variables for the analysis was obtained from a genome-wide association study of ADHD with 19,099 cases and 34,194 controls. The outcome datasets for stroke and its subtypes were obtained from the MEGASTROKE consortium, with 40,585 cases and 406,111 controls. MR inverse variance-weighted method was conducted to investigate the effect of genetic liability to ADHD on ischemic stroke and its subtypes. Sensitivity analyses (median-based methods, MR-Egger, MR-robust adjusted profile scores, MR-pleiotropy residual sum and outlier) were also utilized to assess horizontal pleiotropy and remove outliers. Multivariable MR (MVMR) analyses were conducted to explore potential mediators.

RESULTS

Genetically determined ADHD (per 1 SD) was significantly associated with a higher risk of any ischemic stroke (AIS) (odds ratio (OR) = 1.15, 95% confidence interval (CI) = 1.05-1.25, P = 0.002) and large-artery atherosclerotic stroke (LAS) (OR = 1.40, 95% CI = 1.10-1.76, P = 0.005). The significant association was also found in sensitivity analyses and MVMR analyses.

CONCLUSIONS

Genetic liability to ADHD was significantly associated with an increased risk of AIS, especially LAS. The association between ADHD and LAS was independent of age of smoking initiation but mediated by coronary artery disease.

Subjective and objective assessments are associated for physical function but not cognitive function in community-dwelling stroke survivors

PURPOSE

To investigate the relation between subjectively and objectively assessed cognitive and physical functioning among community-dwelling stroke survivors, and to examine the association of stroke severity with subjectively and objectively assessed cognitive and physical impairments.

MATERIALS AND METHODS

Secondary data analysis was conducted with 127 community-dwelling stroke survivors. For cognitive functioning, objective measures included the NIH Toolbox Cognition Battery and the Executive Function Performance Test; subjective measures included the Quality of Life in Neurological Disorders Applied Cognition. Objective and subjective physical functioning was measured by the NIH Toolbox 2-Minute Walk Test and the Patient-Reported Outcomes Measurement Information System Physical Function, respectively.

RESULTS

A positive correlation was observed between subjective and objective physical functioning, whereas the correlation between subjective and objective cognitive functioning was nonsignificant. Stroke severity was associated with objective cognitive impairment and objective and subjective physical impairment, but not subjective cognitive impairment.

CONCLUSIONS

The lack of association between objective and subjective cognitive functioning challenges the conventional assumption that perceived functioning reflects actual performance. We recommend using both objective and subjective measures to accurately identify cognitive and physical impairment following stroke.Implications for RehabilitationSubjective cognitive functioning is not associated with objective cognitive functioning, suggesting that solely relying on stroke patients' reports is inadequate and may inaccurately estimate patients' actual deficits.Both objective and subjective measures should be used to accurately identify cognitive and physical impairment following stroke.Practitioners should be cognizant of stroke patients' behavioral signs associated with underlying cognitive problems that warrant further evaluation.

Synchronized Cyclograms to Assess Inter-Limb Symmetry during Gait in Post-Stroke Patients

The aim of this study was to assess the inter-limb symmetry during gait in post-stroke patients using the synchronized cyclograms technique. In total, 41 individuals with stroke (21 left and 20 right hemiplegic patients; age: 57.9 ± 12.8 years; time stroke event 4.6 ± 1.8 years) and 48 age-, sex-, and height-matched individuals (control group: CG; age: 54.4 ± 12.5 years) were assessed via 3D gait analysis. Raw kinematic data were processed to compute spatio-temporal parameters (speed, stride length, cadence, stance, swing, and double support phases duration) and angle–angle diagrams (synchronized cyclograms), which were characterized in terms of area, orientation, and trend symmetry indices. The results reveal that all spatio-temporal parameters are characterized by abnormal values, with reduced speed, stride length, cadence, and swing phase duration and increased stance and double support phases duration. With respect to inter-limb symmetry, higher values were found in post-stroke individuals for all the considered parameters as patients generally exhibited a cyclogram characterized by larger areas, higher orientation, and trend symmetry parameters with respect to CG. The described alterations of gait asymmetry are important from a clinical point of view as the achievement of symmetry in gait represents a crucial objective in the rehabilitation of hemiplegic people.

Resting-State Beta-Band Recovery Network Related to Cognitive Improvement After Stroke

Background

Stroke is the second leading cause of death worldwide and it causes important long-term cognitive and physical deficits that hamper patients' daily activity. Neuropsychological rehabilitation (NR) has increasingly become more important to recover from cognitive disability and to improve the functionality and quality of life of these patients. Since in most stroke cases, restoration of functional connectivity (FC) precedes or accompanies cognitive and behavioral recovery, understanding the electrophysiological signatures underlying stroke recovery mechanisms is a crucial scientific and clinical goal.

Methods

For this purpose, a longitudinal study was carried out with a sample of 10 stroke patients, who underwent two neuropsychological assessments and two resting-state magnetoencephalographic (MEG) recordings, before and after undergoing a NR program. Moreover, to understand the degree of cognitive and neurophysiological impairment after stroke and the mechanisms of recovery after cognitive rehabilitation, stroke patients were compared to 10 healthy controls matched for age, sex, and educational level.

Findings

After intra and inter group comparisons, we found the following results: (1) Within the stroke group who received cognitive rehabilitation, almost all cognitive domains improved relatively or totally; (2) They exhibit a pattern of widespread increased in FC within the beta band that was related to the recovery process (there were no significant differences between patients who underwent rehabilitation and controls); (3) These FC recovery changes were related with the enhanced of cognitive performance. Furthermore, we explored the capacity of the neuropsychological scores before rehabilitation, to predict the FC changes in the brain network. Significant correlations were found in global indexes from the WAIS-III: Performance IQ (PIQ) and Perceptual Organization index (POI) (i.e., Picture Completion, Matrix Reasoning, and Block Design).

Predicting the Emergence of Major Neurocognitive Disorder Within Three Months After a Stroke

Background: Neurocognitive disorder (NCD) is common after stroke, with major NCD appearing in about 10% of survivors of a first-ever stroke. We aimed to classify clinical- and imaging factors related to rapid development of major NCD 3 months after a stroke, so as to examine the optimal composition of factors for predicting rapid development of the disorder. We hypothesized that the prediction would mainly be driven by neurodegenerative as opposed to vascular brain changes. Methods: Stroke survivors from five Norwegian hospitals were included from the "Norwegian COgnitive Impairment After STroke" (Nor-COAST) study. A support vector machine (SVM) classifier was trained to distinguish between patients who developed major NCD 3 months after the stroke and those who did not. Potential predictor factors were based on previous literature and included both vascular and neurodegenerative factors from clinical and structural magnetic resonance imaging findings. Cortical thickness was obtained via FreeSurfer segmentations, and volumes of white matter hyperintensities (WMH) and stroke lesions were semi-automatically gathered using FSL BIANCA and ITK-SNAP, respectively. The predictive value of the classifier was measured, compared between classifier models and cross-validated. Results: Findings from 227 stroke survivors [age = 71.7 (11.3), males = (56.4%), stroke severity NIHSS = 3.8 (4.8)] were included. The best predictive accuracy (AUC = 0.876) was achieved by an SVM classifier with 19 features. The model with the fewest number of features that achieved statistically comparable accuracy (AUC = 0.850) was the 8-feature model. These features ranked by their weighting were; stroke lesion volume, WMH volume, left occipital and temporal cortical thickness, right cingulate cortical thickness, stroke severity (NIHSS), antiplatelet medication intake, and education. Conclusion: The rapid (<3 months) development of major NCD after stroke is possible to predict with an 87.6% accuracy and seems dependent on both neurodegenerative and vascular factors, as well as aspects of the stroke itself. In contrast to previous literature, we also found that vascular changes are more important than neurodegenerative ones. Although possible to predict with relatively high accuracy, our findings indicate that the development of rapid onset post-stroke NCD may be more complex than earlier suggested.

Reliability of the Theory of Mind Task Battery (ToM TB) to assess social cognition in post-stroke patients

Theory of mind is the ability to understand, and infer thoughts or mental states to others. This is a central domain of social cognition that can be impaired after brain injury, resulting in changes in social skills and implications for rehabilitation.The aim of this investigation was to analyze the reliability of the Theory of Mind Task Battery (ToM TB) in post-stroke patients.This is a cross-sectional prospective study with psychometric characteristics, involving 38 patients diagnosed with ischemic or hemorrhagic stroke assessed by three examiners using the ToM TB scale, translated and adapted to Brazilian Portuguese. Satisfactory levels of interexaminer agreement were found for almost all categories of the ToM TB: Kappa ranged from 0.036 to 1.00, total score (ICC) from 0.958 to 0.999 and a Cronbach's alpha of 0.658 was obtained with the complete instrument.The Brazilian version of the ToM TB in post-stroke patients is a reliable instrument that can be used to assess the theory of mind, prognosis and rehabilitation of post-stroke patients.

[Therapy of moderate cognitive impairment in the early recovery period of ischemic stroke]

OBJECTIVE

To assess the efficacy and safety of prospecta in the treatment of moderate cognitive impairment in the early recovery period of ischemic stroke.

MATERIAL AND METHODS

The study included 275 patients (mean age 64.0±8.1 years) with a history of single ischemic stroke from 3 to 6 months, with moderate cognitive impairment, and moderate activity in everyday life, who were randomized in two groups. During the screening phase, the severity of cognitive impairment was assessed with the Mini-Mental State Examination and Montreal Cognitive Assessment scales; the level of activity in everyday life was evaluated with the Barthel Scale; and quality of life was assessed with the Stroke Specific Quality of Life Scale. Patients took 2 tablets of prospecta or placebo 2 times a day for 24 weeks. The follow-up period was 4 weeks. The primary endpoint of the study was the proportion of patients with improvement in cognitive function (+1 or more on the MoCA test) after 24 weeks of treatment. The occurrence and type of adverse events (AEs), their severity, relationship to the drug, outcome, changes in vital signs, and the proportion of patients with clinically significant abnormality in laboratory tests were analyzed to assess the safety.

RESULTS

A clinically significant improvement in cognitive function was obtained in 91.9% of patients in the prospecta group vs 82.,1% in the placebo group, (p=0.02). There were 57 AEs in 37 (27.4%) Prospecta group patients and 53 AEs in 39 (27.9%) Placebo group participants (p=1.00). No AEs were certainly associated with taking the medication. No clinically significant changes in vital signs or abnormal laboratory results were detected during the study.

CONCLUSION

Prospecta is an effective and safe treatment option for patients with moderate cognitive impairment in the early recovery period of ischemic stroke.

Clinical correlates of social cognition after an ischemic stroke: preliminary findings

The co-occurrence of post-stroke behavioral disorders and cognitive impairment has been extensively investigated. However, studies usually do not include social cognition among the assessed cognitive domains.

Objective

To investigate the potential association between facial emotion recognition, a measure of social cognition, and behavioral and cognitive symptoms in the subacute phase of ischemic stroke.

Methods

Patients admitted to a Stroke Unit with ischemic stroke were followed up to 60 days. At this time point, they were evaluated with the following tools: Mini-Mental State Examination (MMSE); Frontal Assessment Battery (FAB); Visual Memory Test of the Brief Cognitive Battery (VMT); Phonemic Verbal Fluency (F-A-S Test); Digit Span; Facial Emotion Recognition Test (FERT) and Hospital Anxiety and Depression Scale (HADS). A control group composed of 21 healthy individuals also underwent the same evaluation.

Results

Eighteen patients with ischemic stroke were enrolled in this study. They had similar age, sex and schooling years compared to controls. Depression symptoms and episodic memory deficits were significantly more frequent in patients compared to controls. The recognition of sadness expression positively correlated with the levels of anxiety and depression, while and the recognition of fear expression negatively correlated with depression in the stroke group.

Conclusions

After an ischemic stroke, patients exhibit impairment in social cognition skills, specifically facial emotion recognition, in association with behavioral symptoms.

Quality of Life in Physical, Social, and Cognitive Domains Improves With Endovascular Therapy in the DEFUSE 3 Trial

BACKGROUND AND PURPOSE

The DEFUSE 3 (Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke 3) randomized clinical trial demonstrated the efficacy of endovascular therapy in treating ischemic stroke 6 to 16 hours after onset, resulting in better functional outcomes than standard medical therapy alone. The objective of this secondary analysis is to analyze the effect of late-window endovascular treatment of ischemic stroke on quality of life (QoL) outcomes.

METHODS

Patients (n=182) who presented between 6 and 16 hours after they were last known to be well with acute anterior circulation ischemic stroke were randomized to endovascular thrombectomy plus standard medical therapy or standard medical therapy alone and followed-up through 90 days poststroke. QoL at day 90 was assessed with the QoL in Neurological Disorders measurement tool.

RESULTS

Of the 146 subjects alive at day 90, 136 (95%) filled out QoL in Neurological Disorders short forms. Patients treated with endovascular therapy had better QoL scores in each domain: mobility, social participation, cognitive function, and depression (P<0.01 for all). Variables other than endovascular therapy that were independently associated with better QoL included lower baseline National Institutes of Health Stroke Scale, younger age, and male sex. The degree to which the modified Rankin Scale captures differences in QoL between patients varied by domain; the modified Rankin Scale score accounted for a high proportion of the variability in mobility (Rs²=0.82), a moderate proportion in social participation (Rs²=0.62), and a low proportion in cognition (Rs²=0.31) and depression (Rs²=0.19).

CONCLUSIONS

Patients treated with endovascular therapy 6 to 16 hours after stroke have better QoL than patients treated with medical therapy alone, including better mobility, more social participation, superior cognition, and less depression. The modified Rankin Scale fails to capture patients' outcomes in cognition and depression, which should therefore be assessed with dedicated QoL tools. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02586415.

Social psychological mechanisms and processes in a novel, health professional-led, self-management intervention for older stroke individuals: a synthesis and phenomenological study

BACKGROUND

A good portion of stroke patients in Western countries are over 65 of age. Because of sequelae, they often lead more isolated lives after the stroke. In terms of social reintegration, this group of patients is especially vulnerable. Reintegration into the community post-stroke greatly depends on support from family. However, the stroke individual's closest relatives are at risk of becoming overburdened. The objectives are to describe the social psychological mechanisms and processes involved in a novel self-management intervention, and to evaluate their feasibility and acceptability from the stroke individuals', the informal caregivers' and the mentors' perspectives, before implementation into a randomised controlled trial.

METHODS

Qualitative interviews were conducted and analysed using a phenomenological approach. Informants comprised four stroke individuals, three informal caregivers and two mentors. The UK Medical Research Council Framework for developing and evaluating complex interventions was used in the evaluation design of the intervention.

RESULTS

Six social psychological mechanisms were revealed as the mentors' focus areas in their interaction with stroke individuals and informal caregivers: a) Tailored approach - by individual preferences, b) Dialogue-based communication, c) Development of a good relationship, d) Transfer of activities to everyday and social contexts, e) Involvement of relatives and social networks, and f) Supporting tools - to optimise actions and communication. Furthermore, interaction processes between the stroke individual and the informal caregiver and the mentors occurred, and generated processes of change and learning in the stroke individual and the informal caregiver. The mechanisms and processes described were perceived as feasible and acceptable to the informants - with the exception of the technological supporting tool.

CONCLUSION

The social psychological mechanisms and processes involved in the intervention indicated a positive association to self-management behaviour from the informants' perspectives. The informants evaluated them to be relevant and meaningful in the novel self-management intervention.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03183960. Reg. June 15, 2017.

Psychometric properties of cognitive screening for patients with cerebrovascular diseases A systematic review

Screening instruments are ideal for acute clinical settings because they are easy to apply, fast, inexpensive and sensitive for specific samples. However, there is a need to verify the psychometric properties of screening in stroke patients.

Objective

This study investigated the psychometric properties (methodological procedures) of cognitive screening for patients with cerebrovascular diseases.

Methods

A systematic review of papers published on PsycINFO, Web of Knowledge, PubMed and Science Direct (2005 to 2016) was performed.

Results

A total of 55 articles remained after applying exclusion criteria. The samples ranged from 20 to 657 patients. Most articles evaluated elderly individuals with four to 13 years of education who had experienced ischemic or hemorrhagic stroke. There was a tendency to find evidence of validity for criteria and to analyze the sensitivity/specificity of the instruments. Although the studies frequently used the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) to seek evidence of validity and reliability, the use of these instruments among stroke patients has been criticized due to their psychometric properties and the neuropsychological functions evaluated.

Conclusion

Although there is no gold standard screen for assessing adults post-stroke, instruments devised specifically for this population have shown promise. This review helps both researchers and clinicians to select the most appropriate screen for identifying cognitive impairment in adults post-stroke.

Effect of the Wii Sports Resort on the improvement in attention, processing speed and working memory in moderate stroke

BACKGROUND

Stroke is the most common neurological disease in the world. After the stroke, some people suffer a cognitive disability. Commercial videogames have been used after stroke for physical rehabilitation; however, their use in cognitive rehabilitation has hardly been studied. The objectives of this study were to analyze attention, processing speed, and working memory in patients with moderate stroke after an intervention with Wii Sports Resort and compared these results with a control group.

METHODS

A pre-post design study was conducted with 30 moderate stroke patients aged 65 ± 15. The study lasted eight weeks. 15 participated in the intervention group and 15 belong to the control group. They were assessed in attention and processing speed (TMT-A and B) and working memory (Digit Span of WAIS-III). Parametric and effect size tests were used to analyze the improvement of those outcomes and compared both groups.

RESULTS

At the baseline, there was no difference between TMT-A and B. A difference was found in the scalar score of TMT-B, as well as in Digit Backward Span and Total Digit Task. In TMT-A and B, the intervention group had better scores than the control group. The intervention group in the Digit Forward Span and the Total Digit obtained a moderate effect size and the control group also obtained a moderate effect size in Total Digit. In the Digit scalar scores, the control group achieved better results than the intervention group.

CONCLUSIONS

The results on attention, processing speed and working memory improved in both groups. However, according to the effect sizes, the intervention group achieved better results than the control group. In addition, the attention and processing speed improved more than the working memory after the intervention. Although more studies are needed in this area, the results are encouraging for cognitive rehabilitation after stroke.