Cognitive Reserve as an Emerging Concept in Stroke Recovery

Cognition and Cognitive Reserve

Cognition is a mental process that provides the ability to think, know, and learn. Though cognitive skills are necessary to do daily tasks and activities, cognitive aging causes changes in various cognitive functions. Cognitive abilities that are preserved and strengthened by experience can be kept as a reserve and utilized when necessary. The concept of reserving cognition was found when people with Alzheimer's disease had differences in clinical manifestations and cognitive functions. The cognitive reserve builds resilience against cognitive decline and improves the quality of life. Also, several lines of studies have found that the plasticity between neurons has a significant impact on cognitive reserve and acts against cognitive decline. To extend the findings, the present study provides a comprehensive understanding of cognitive reserve and the variables that are involved in maintaining cognition. The study also considers reading as one of the cognitive proxies that develops and maintains cognitive reserve.

Dopaminergic mesolimbic structural reserve is positively linked to better outcome after severe stroke

The concept of brain reserve capacity has emerged in stroke recovery research in recent years. Imaging-based biomarkers of brain health have helped to better understand outcome variability in clinical cohorts. Still, outcome inferences are far from being satisfactory, particularly in patients with severe initial deficits. Neurorehabilitation after stroke is a complex process, comprising adaption and learning processes, which, on their part, are critically influenced by motivational and reward-related cognitive processes. Amongst others, dopaminergic neurotransmission is a key contributor to these mechanisms. The question arises, whether the amount of structural reserve capacity in the dopaminergic system might inform about outcome variability after severe stroke. For this purpose, this study analysed imaging and clinical data of 42 severely impaired acute stroke patients. Brain volumetry was performed within the first 2 weeks after the event using the Computational Anatomy Toolbox CAT12, grey matter volume estimates were collected for seven key areas of the human dopaminergic system along the mesocortical, mesolimbic and nigrostriatal pathways. Ordinal logistic regression models related regional volumes to the functional outcome, operationalized by the modified Rankin Scale, obtained 3-6 months after stroke. Models were adjusted for age, lesion volume and initial impairment. The main finding was that larger volumes of the amygdala and the nucleus accumbens at baseline were positively associated with a more favourable outcome. These data suggest a link between the structural state of mesolimbic key areas contributing to motor learning, motivational and reward-related brain networks and potentially the success of neurorehabilitation. They might also provide novel evidence to reconsider dopaminergic interventions particularly in severely impaired stroke patients to enhance recovery after stroke.

Considering the response in addition to the challenge - a narrative review in appraisal of a motor reserve framework

The remarkable increase in human life expectancy over the past century has been achieved at the expense of the risk of age-related impairment and disease. Neurodegeneration, be it part of normal aging or due to neurodegenerative disorders, is characterized by loss of specific neuronal populations, leading to increasing clinical impairment. The individual course may be described as balance between aging- or disease-related pathology and intrinsic mechanisms of adaptation. There is plenty of evidence that the human brain is provided with exhaustible resources to maintain function in the face of adverse conditions. While a reserve concept has mainly been coined in cognitive neuroscience, emerging evidence suggests similar mechanisms to underlie individual differences of adaptive capacity within the motor system. In this narrative review, we summarize what has been proposed to date about a motor reserve (mR) framework. We present current evidence from research in aging subjects and people with neurological conditions, followed by a description of what is known about potential neuronal substrates of mR so far. As there is no gold standard of mR quantification, we outline current approaches which describe various indicators of mR. We conclude by sketching out potential future directions of research. Expediting our understanding of differences in individual motor resilience towards aging and disease will eventually contribute to new, individually tailored therapeutic strategies. Provided early diagnosis, enhancing the individual mR may be suited to postpone disease onset by years and may be an efficacious contribution towards healthy aging, with an increased quality of life for the elderly.

The role of cognitive reserve in traumatic brain injury: a systematic review of observational studies

OBJECTIVE

Evaluate the role of cognitive reserve (CR) on cognitive and physical sequelae in traumatic brain injury (TBI).

METHODS

A comprehensive search strategy was conducted in four databases in English and Spanish in the last 12 years (2011-2023). Inclusion criteria: original cross-sectional and longitudinal studies whose main or secondary objective was to evaluate the effect of CR in adult patients with TBI. PRISMA guidelines were used to report the search and selection method and STROBE checklist was used to evaluate the quality of studies.

RESULTS

Eighteen observational studies were included in this review. Multiple sources of variability were observed: number of patients, time of evolution, severity of the TBI, type of CR proxy, cognitive assessment instrument, etc. However, the most commonly used indicators of CR were premorbid IQ and educational attainment. A positive and consistent association between CR and performance on cognitive tests after injury was found.

CONCLUSIONS

CR has a consistent positive effect on cognition and on some other aspects of recovery in traumatic brain injury. In future studies, it will be necessary to promote the use of CR indices based on various indicators and explore the effects of CR on other aspects related to the recovery of brain trauma.

Insights gained over 60 years on factors shaping post-stroke aphasia recovery: A commentary on Vignolo (1964)

Aphasia is an acquired language disorder resulting from brain injury, including strokes which is the most common etiology, neurodegenerative diseases, tumors, traumatic brain injury, and resective surgery. Aphasia affects a significant portion of stroke survivors, with approximately one third experiencing its debilitating effects in the long term. Despite its challenges, there is growing evidence that recovery from aphasia is possible, even in the chronic phase of stroke. Sixty years ago, Vignolo (1964) outlined the primary challenges confronted by researchers in this field. These challenges encompassed the absence of an objective evaluation of language difficulties, the scarcity of evidence regarding spontaneous aphasia recovery, and the presence of numerous variables that could potentially influence the process of aphasia recovery. In this paper, we discuss the remarkable progress that has been made in the assessment of language and communication in aphasia as well as in understanding the factors influencing post-stroke aphasia recovery.

Post-Stroke Brain Health Monitoring and Optimization: A Narrative Review

Significant advancements have been made in recent years in the acute treatment and secondary prevention of stroke. However, a large proportion of stroke survivors will go on to have enduring physical, cognitive, and psychological disabilities from suboptimal post-stroke brain health. Impaired brain health following stroke thus warrants increased attention from clinicians and researchers alike. In this narrative review based on an open timeframe search of the PubMed, Scopus, and Web of Science databases, we define post-stroke brain health and appraise the body of research focused on modifiable vascular, lifestyle, and psychosocial factors for optimizing post-stroke brain health. In addition, we make clinical recommendations for the monitoring and management of post-stroke brain health at major post-stroke transition points centered on four key intertwined domains: cognition, psychosocial health, physical functioning, and global vascular health. Finally, we discuss potential future work in the field of post-stroke brain health, including the use of remote monitoring and interventions, neuromodulation, multi-morbidity interventions, enriched environments, and the need to address inequities in post-stroke brain health. As post-stroke brain health is a relatively new, rapidly evolving, and broad clinical and research field, this narrative review aims to identify and summarize the evidence base to help clinicians and researchers tailor their own approach to integrating post-stroke brain health into their practices.

Education Level Modulates the Presence of Poststroke Depression and Anxiety, But It Depends on Age

ABSTRACT

Depression and anxiety are common complications after stroke and little is known about the modulatory roles of education and age. Our study aimed to evaluate the modulatory effects of education level on anxiety and depression after stroke and their effect on each age group. Adults with first stroke took part in this cross-sectional observational clinical study. We used the following instruments: Hospital Anxiety and Depression Scale (HADS), Montreal Cognitive Scale, Pittsburgh Sleep Quality Index, Barthel index, and Functional Independence Measure. There were 89 patients. The mean (SD) age was 58.01 (13) years, mean (SD) years of education was 9.91 (5.22), 55.1% presented depression symptoms and 47.2% anxiety symptoms, 56.2% were young adults and 43.8% were older adults. We identified a negative association between education and anxiety score (r = -0. 269, p = 0.011) and depression score (r = -0.252, p = 0.017). In the linear regression analysis, we found that education is negatively associated with HADS, but this influence was more consistent in young adults. In conclusion, a higher education level reduces the risk of depression and anxiety, but their effect is less consistent in older adults.

Rapid Effects of BCI-Based Attention Training on Functional Brain Connectivity in Poststroke Patients: A Pilot Resting-State fMRI Study

The prevalence of stroke-induced cognitive impairment is high. Effective approaches to the treatment of these cognitive impairments after stroke remain a serious and perhaps underestimated challenge. A BCI-based task-focused training that results in repetitive recruitment of the normal motor or cognitive circuits may strengthen stroke-affected neuronal connectivity, leading to functional improvements. In the present controlled study, we attempted to evaluate the modulation of neuronal circuits under the influence of 10 days of training in a P3-based BCI speller in subacute ischemic stroke patients.

Is cognitive reserve associated with the prevention of cognitive decline after stroke? A Systematic review and meta-analysis

OBJECTIVE

To conduct a systematic review and meta-analyses of the effect of socio-behavioral cognitive reserve (CR) proxies on cognitive decline after stroke.

METHOD

Three journal search and indexing databases (PubMed, Scopus and Web of Sciences) were crossed to examine the scientific evidence systematically. In addition, meta-analytic techniques, using mixed-effect methods, were carried out to estimate the impact (pooled effect size) of CR proxies on either dementia incidence or cognitive decline after stroke.

RESULTS

Twenty-two studies were included in the systematic revision, whereas nineteen of them were eligible for the meta-analysis. The findings showed that high education is associated with a decreased rate of post-stroke dementia. Moreover, other CR proxies (e.g., occupation, bilingualism or social interaction) demonstrate a protective effect against non-dementia cognitive decline after stroke, although some inconsistencies were found in the literature. Regarding the meta-analysis, occupational attainment and education) showed a protective effect against post-stroke cognitive impairment diagnosis in comparison with a mixed category of different CR proxies. Second, a main cognitive change effect was found, pointing to greater cognitive change after stroke in those with low vs. high CR.

CONCLUSIONS

Our findings emphasize that CR may prevent cognitive decline after stroke, but this effect can be modulated by different factors such the CR proxy and individual characteristics such as age or type of lesion. The methodological divergences of the studies (i.e., follow-up intervals, cognitive outcomes) need unification to diminish external sources of variability for predicting rates of cognitive decline after stroke.

Cognitive Recovery After Stroke: Memory

Memory impairment occurs in over a third of patients after symptomatic stroke. Memory deficits rarely occur in isolation but are an important component of the poststroke cognitive syndrome because of the strong relationship with the risk of poststroke dementia. In this review, we summarize available data on impairment of episodic memory, with a particular emphasis on the natural history of memory impairment after stroke and the factors influencing trajectory informed by an updated systematic review. We next discuss the pathophysiology of memory impairment and mechanisms of both decline and recovery of function. We then turn to the practical issue of measurement of memory deficits after stroke, emerging biomarkers, and therapeutic approaches. Our review identifies critical gaps, particularly in studies of the natural history that properly map the long-term trajectory of memory and the associations with factors that modulate prognosis. Few studies have used advanced neuroimaging and this, in conjunction with other biomarker approaches, has the potential to provide a much richer understanding of the mechanisms at play and promising therapeutic avenues.

Simultaneous real-time EEG-fMRI neurofeedback: A systematic review

Neurofeedback (NF) is a biofeedback technique that teaches individuals self-control of brain functions by measuring brain activations and providing an online feedback signal to modify emotional, cognitive, and behavioral functions. NF approaches typically rely on a single modality, such as electroencephalography (EEG-NF) or a brain imaging technique, such as functional magnetic resonance imaging (fMRI-NF). The introduction of simultaneous EEG-fMRI tools has opened up the possibility of combining the high temporal resolution of EEG with the high spatial resolution of fMRI, thereby increasing the accuracy of NF. However, only a few studies have actively combined both techniques. In this study, we conducted a systematic review of EEG-fMRI-NF studies (N = 17) to identify the potential and effectiveness of this non-invasive treatment for neurological conditions. The systematic review revealed a lack of homogeneity among the studies, including sample sizes, acquisition methods in terms of simultaneity of the two procedures (unimodal EEG-NF and fMRI-NF), therapeutic targets field, and the number of sessions. Indeed, because most studies are based on a single session of NF, it is difficult to draw any conclusions regarding the therapeutic efficacy of NF. Therefore, further research is needed to fully understand non-clinical and clinical potential of EEG-fMRI-NF.

Systematic review on post-stroke computerized cognitive training: Unveiling the impact of confounding factors

Background

Stroke is a highly incapacitating disease that can lead to disabilities due to cognitive impairment, physical, emotional, and social sequelae, and a decrease in the quality of life of those affected. Moreover, it has been suggested that cognitive reserve (patients' higher levels of education or having a skilled occupation), for instance, can promote faster cognitive recovery after a stroke. For this reason, this review aims to identify the cognitive, functional, and behavioral effects of computerized rehabilitation in patients aged 50 years or older who had a stroke, considering cognitive reserve proxies.

Methods

We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis-PRISMA, and performed the search for peer-reviewed randomized controlled trials without a date restriction on CINAHL, LILACS, PubMed, Scopus, and Web of Science databases were chosen.

Results

We screened 780 papers and found 19 intervention studies, but only 4 met the inclusion criteria and shared data. These studies included computerized tools for motor and cognitive rehabilitation in the experimental groups. In all studies, computerized training was combined with other interventions, such as standard therapy, occupational therapy, and aerobic exercises. There were 104 participants affected by ischemic or hemorrhagic stroke, predominantly male (57.69%), and all with cognitive impairment.

Conclusion

Despite a limited number of studies, varied methods and insufficient information available, schooling as a CR proxy combined with high-intensity computerized cognitive training was key to mediating cognitive improvement. The systematic review also identified that the associated ischemic stroke and shorter time of onset for rehabilitation contribute to the cognitive evolution of patients. Findings do not support a greater benefit of computerized cognitive training compared to conventional cognitive therapies.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=296193], identifier [CRD42022296193].

The moderating effect of cognitive reserve on cognitive function in patients with Acute Ischemic Stroke

Background

Recovery of cognitive function after stroke has inter-individual variability. The theory of cognitive reserve offers a potential explanation of the variability in cognitive function after stroke.

Objective

This study aimed to investigate the moderating effect of cognitive reserve on the relationship between the stroke severity and cognitive function after stroke.

Materials and methods

A total of 220 patients with Acute Ischemic Stroke (AIS) were recruited in 2021 from two stroke centers in Nanjing, China. The National Institutes of Health Stroke Scale (NIHSS) was used to assess stroke severity upon admission. Cognitive Reserve Index questionnaire (CRIq) and validated Montreal Cognitive Assessment, Changsha Version (MoCA-CS) were used to assess cognitive reserve and cognitive function within 7 days after stroke onset, respectively. A series of multivariate linear regression models were applied to test the moderating effect of cognitive reserve.

Results

Patients with a higher level of cognitive reserve had better cognitive function after stroke compared with those with a lower level of cognitive reserve (β = 0.074, p = 0.003). The interaction of NIHSS and cognitive reserve was statistically significant (β = −0.010, p = 0.045) after adjusting for some key covariates [e.g., age, marital status, Oxfordshire Community Stroke Project (OCSP) classification, Trial of ORG 10172 in Acute Stroke Treatment (TOAST) classification, cerebral vascular stenosis, diabetes and atrial fibrillation].

Conclusion

Cognitive reserve may help to buffer the effect of stroke-related pathology on cognitive decline in Chinese acute stroke patients. Enhancing cognitive reserve in stroke patients may be one of the potential strategies for preventing vascular dementia.

Frontoparietal network activation is associated with motor recovery in ischemic stroke patients

Strokes cause lesions that damage brain tissue, disrupt normal brain activity patterns and can lead to impairments in motor function. Although modulation of cortical activity is central to stimulation-based rehabilitative therapies, aberrant and adaptive patterns of brain activity after stroke have not yet been fully characterized. Here, we apply a brain dynamics analysis approach to study longitudinal brain activity patterns in individuals with ischemic pontine stroke. We first found 4 commonly occurring brain states largely characterized by high amplitude activations in the visual, frontoparietal, default mode, and motor networks. Stroke subjects spent less time in the frontoparietal state compared to controls. For individuals with dominant-hand CST damage, more time spent in the frontoparietal state from 1 week to 3-6 months post-stroke was associated with better motor recovery over the same time period, an association which was independent of baseline impairment. Furthermore, the amount of time spent in brain states was linked empirically to functional connectivity. This work suggests that when the dominant-hand CST is compromised in stroke, resting state configurations may include increased activation of the frontoparietal network, which may facilitate compensatory neural pathways that support recovery of motor function when traditional motor circuits of the dominant-hemisphere are compromised.

Predictors beyond the lesion: Health and demographic factors associated with aphasia severity

BACKGROUND

Lesion-related factors are associated with severity of language impairment in persons with aphasia. The extent to which demographic and health factors predict language impairment beyond traditional cortical measures remains unknown. Identifying and understanding the contributions of factors to predictive models of severity constitutes critical knowledge for clinicians interested in charting the likely course of aphasia in their patients and designing effective treatment approaches in light of those predictions.

METHODS

Utilizing neuroimaging and language testing from our cohort of 224 individuals in the chronic stage of recovery from a left-hemisphere stroke in a cross-sectional study, we first conducted a lesion symptom mapping (LSM) analysis to identify regions associated with aphasia severity scores. After controlling for lesion volume and damage to pre-identified areas, three models were created to predict severity scores: 1) Demographic Model (N = 147); 2) Health Model (N = 106); and 3) Overall Model (N = 106). Finally, all identified factors were entered into a Final Model to predict raw severity scores.

RESULTS

Two areas were associated with aphasia severity-left posterior insula and left arcuate fasciculus. The results from the Demographic Model revealed non-linguistic cognitive ability, age at stroke, and time post-stroke as significant predictors of severity (P = .005; P = .02; P = .001, respectively), and results from the Health Model suggested the extent of leukoaraiosis is associated with severity (P = .0004). The Overall Model showed a relationship between aphasia severity and cognitive ability (P = .01), time post-stroke (P = .002), and leukoaraiosis (P = .01). In the Final Model, which aimed to predict raw severity scores, demographic, health, and lesion factors explained 55% of the variance in severity, with health and demographic factors uniquely explaining nearly half of performance variance.

CONCLUSIONS

Results from this study add to the literature suggesting patient-specific variables can shed light on individual differences in severity beyond lesion factors. Additionally, our results emphasize the importance of non-linguistic cognitive ability and brain health in aphasia recovery.

Association of cognitive reserve with stroke outcome: a protocol for a systematic review

INTRODUCTION

The concept of cognitive reserve (CR) was introduced to account for individual differences in the clinical manifestation of neurodegenerative diseases. Though several mechanisms and risk factors are shared between neurodegeneration and stroke, the effect of CR on poststroke functional outcome has been poorly addressed. This systematic review aims to synthesise the available research evidence on the association of CR with stroke outcome, in order to implement the understanding of interindividual variability in stroke outcome and to improve its prediction.

METHODS AND ANALYSIS

Cochrane Library, Embase, PubMed, Web of Science and reference lists of relevant literature will be searched for publications on CR proxies (eg, education, years of education, occupational attainment, premorbid intelligence) and stroke outcome, published between 1 January 1980 and 10 March 2022. Two reviewers will independently perform the study selection, data extraction and quality assessment. Disagreements between reviewers will be resolved by a third independent reviewer. The Quality In Prognosis Studies tool will be used to assess the quality of each included study. The primary outcome will be functional outcome after stroke assessed with modified Rankin Scale, activities of daily living (eg, Barthel Index), National Institute of Health Stroke Scale, dichotomised as favourable versus not favourable as well as reported as continuous or ordinal variables. Qualitative and quantitative findings will be summarised and, if possible, data will be synthesised using appropriate meta-analytical methods. The quality of evidence will be assessed using the Grading of Recommendations Assessment, Development and Evaluation framework.

ETHICS AND DISSEMINATION

No ethical approval is required as it is a protocol for a systematic review and the data used will be extracted from published studies. The findings from this systematic review will be disseminated in a peer-reviewed scientific journal and presented at conferences. The data will be made freely available.

PROSPERO REGISTRATION NUMBER

CRD42021256175.

Education and Literacy as Risk Factors of Dementia after Stroke and Transient Ischemic Attack: NEDICES Study

Background: A protective effect of education on cognitive decline after stroke has been claimed, but evidence from prospective population-based cohorts is very limited. The differential role of literacy and education on dementia after stroke remains unexplored. Objective: This research addresses the role of education and literacy in dementia incidence after stroke and transient ischemic attack (TIA). Methods: 131 participants with stroke or TIA were identified within the population-based NEDICES study (N = 5,278 persons). Participants were fully assessed at baseline (1994–1995) and incident dementia diagnosis was made by expert neurologists (DSM-IV criteria) after a mean follow-up of 3.4 years. Adjusted Cox regression analyses were applied to test the association between education, literacy, and dementia risk. Results: Within the 131 subjects with stroke or TIA, 19 (14%) developed dementia at follow-up. The Cox’s regression model (age and sex adjusted) showed that low education (HR = 3.48, 95% CI = 1.28, 9.42, p = 0.014) and literacy (HR = 3.16, 95% CI = 1.08, 9.22, p = 0.035) were significantly associated with a higher dementia risk. Low education was also associated with dementia when main confounders (i.e., cognitive/functional performance) were considered in the Cox’s model. However, after including stroke recurrence, only low/null literacy (versus education) remained as significant predictor of dementia. Finally, low/null literacy showed an effect over-and-above education on dementia risk when both factors were introduced in the adjusted Cox’s regression. Conclusion: These findings underline the importance of literacy to estimate cognitive decline after stroke in low-educated populations.

Cognition and Cognitive Reserve in Cochlear Implant Recipients

At present, dementia is a hot topic. Hearing loss is considered to be a modifiable risk factor for cognitive decline. The underlying mechanism remains unclear and might be mediated by socioeconomic and psychosocial factors. Cochlear implantation has been shown not only to restore auditory abilities, but also to decrease mental distress and to improve cognitive functions in people with severe hearing impairment. However, the promising results need to be confirmed. In a prospective single-center study, we tested the neurocognitive abilities of a large group of 71 subjects with bilateral severe hearing impairment with a mean age of 66.03 (SD = 9.15) preoperatively and 6, 12, and 24 months after cochlear implantation using a comprehensive non-auditory computer-based test battery, and we also assessed the cognitive reserve (CR) [Cognitive Reserve Index (CRI)], health-related quality of life (QoL) (Nijmegen Cochlear Implant Questionnaire), and depression (Geriatric Depression Scale-15). Cognitive functions significantly increased after 6 months in attention (p = 0.00004), working memory (operation span task; p = 0.002), and inhibition (p = 0.0002); and after 12 months in recall (p = 0.003) and verbal fluency (p = 0.0048), and remained stable up to 24 months (p ≥ 0.06). The CR positively correlated with cognitive functions pre- and post-operatively (both p < 0.005), but postoperative improvement in cognition was better in subjects with poor CR (p = 0.003). Depression had only a slight influence on one subtest. No correlation was found among cognitive skills, quality of life, and speech perception (each p ≥ 0.05). Cochlear implantation creates an enriched environment stimulating the plasticity of the brain with a global positive impact on neurocognitive functions, especially in subjects with poor preoperative cognitive performance and low cognitive reserve.

The influence of cognitive reserve in the protection of the cognitive status after an acquired brain injury: A systematic review

BACKGROUND

Cognitive Reserve (CR) hypothesis was introduced to account for the variability in cognitive performance of patients with similar degrees of brain injury or pathology. The individual variability of CR is modulated by the interaction of innate capacities and exposures throughout life, which can act as protectors against neuropathology's clinical effects. Individuals with higher CR appear to have better cognitive performance after a brain injury. The present review aimed to identify and map the scientific evidence available in literature regarding CR's influence in protecting the cognitive status after an Acquired Brain Injury (ABI).

METHOD

A systematic review was performed for published studies until October 2020 in PubMed, Scopus, and CINAHL electronic databases. Studies regarding CR's influence in protecting the cognitive status after an ABI were included in this review. The Newcastle-Ottawa Scale was used to assess risk of bias in the included studies. This systematic review was recorded in the International Prospective Register of Systematic Reviews (PROSPERO) under the number CRD42021236594.

RESULTS

Twenty-one studies published between 2003 and 2020 were selected and analyzed. The literature analysis showed that CR has a positive effect on cognitive status after an ABI. Various proxies were used to estimate CR, including estimated premorbid IQ, education, occupation attainment, socioeconomic status, leisure activities, bilingualism, and social integration. CR proxies constitute a set of variables that may have a significant influence on cognitive status. Higher CR levels were associated with lower cognitive impairment after an ABI.

CONCLUSIONS

Although more research is necessary for a complete understanding of CR's impact on cognition, the synthesis of these studies confirmed that there is evidence on the beneficial impact of CR on cognitive status after an ABI. These findings support CR's cognitive status role following an ABI and may provide additional information for prognosis and rehabilitation plans.

Factors associated with paid employment 12 months after stroke in A Very Early Rehabilitation Trial (AVERT)

BACKGROUND

Returning to work is an important outcome for stroke survivors.

OBJECTIVES

This sub-study of a randomised controlled trial aimed to provide characteristics of working-age stroke participants and identify factors associated with return to work at 12 months.

METHODS

We used paid employment data collected as part of A Very Early Rehabilitation Trial (AVERT, n=2104), an international randomised controlled trial studying the effects of very early mobilisation after stroke at 56 acute stroke units across Australia, New Zealand, the United Kingdom, Malaysia and Singapore. For the present analysis, data for trial participants < 65 years old were included if they were working at the time of stroke and had complete 12-month return-to-work data. The primary outcome was 12-month return to paid work. Univariable and multivariable logistic regression analyses were conducted to determine the association of multiple factors with return to work.

RESULTS

In total, 376 AVERT participants met the inclusion criteria for this sub-study. By 12 months, 221 (59%) participants had returned to work at a median of 38 hr per week. Similar rates were found across geographic regions. On univariable analysis, the odds of returning to paid employment were increased with younger age (OR per year 0.95, 95%CI 0.92-0.97), no previous diabetes (0.4, 0.24-0.67), lower stroke severity (OR per National Institutes of Health Stroke Scale point 0.82, 0.78-0.86), less 3-month depressive traits (Irritability Depression Anxiety [IDA] scale) (OR per IDA point 0.87, 0.80-0.93), less 3-month disability (modified Rankin Scale), and prior full-time work (2.04, 1.23-3.38). On multivariable analysis, return to work remained associated with younger age (OR 0.94, 95%CI 0.91-0.98), lower stroke severity (0.92, 0.86-0.99), prior full-time work (2.33, 1.24-4.40), and less 3-month disability.

CONCLUSIONS

Return to work at 12 months after stroke was associated with young age, acute stroke severity, 3-month disability and full-time employment before stroke. Greater understanding of this topic could help in developing programs to support successful resumption of work post-stroke.

Association of Depression and Anxiety With Cognitive Impairment 6 Months After Stroke

OBJECTIVE

To investigate the associations between general cognitive impairment and domain-specific cognitive impairment with depression and anxiety at 6 months poststroke.

METHODS

Participants were patients with confirmed acute stroke from the OCS-Care Study who were recruited on stroke wards in a multisite study and followed up at a 6-month poststroke assessment. Depression and anxiety symptoms were assessed by the Hospital Anxiety and Depression Scale subscales, with scores greater than 7 indicating possible mood disorders. General cognitive impairment at follow-up was assessed using the Montreal Cognitive Assessment (MoCA); stroke-specific cognitive domain impairments were assessed using the Oxford Cognitive Screen (OCS). Linear regression was used to examine the associations between cognition and depression/anxiety symptoms at 6 months, controlling for acute stroke severity and activities of daily living impairment, age, sex, education, and co-occurring poststroke depression/anxiety.

RESULTS

A total of 437 participants (mean age, 69.28 years [SD 12.17], 226 male [51.72%]) were included in analyses. Six-month poststroke depression (n = 115, 26%) was associated with 6-month impairment on the MoCA (β = 0.96, standard error [SE] 0.31, p = 0.006) and all individual domains assessed by the OCS: spatial attention (β = 0.67, SE 0.33, p = 0.041), executive function (β = 1.37, SE 0.47, p = 0.004), language processing (β = 0.87, SE 0.38, p = 0.028), memory (β = 0.76, SE 0.37, p = 0.040), number processing (β = 1.13, SE 0.40, p = 0.005), and praxis (β = 1.16, SE 0.49, p = 0.028). Poststroke anxiety (n = 133, 30%) was associated with impairment on the MoCA (β = 1.47, SE 0.42, p = 0.001) and spatial attention (β = 1.25, SE 0.45, p = 0.006); these associations did not remain significant after controlling for co-occurring poststroke depression.

CONCLUSION

Domain-general and domain-specific poststroke cognitive impairment was found to be highly related to depressive symptomatology but not anxiety symptomatology.

Main Concept, Sequencing, and Story Grammar Analyses of Cinderella Narratives in a Large Sample of Persons with Aphasia

Recently, a multilevel analytic approach called Main Concept, Sequencing, and Story Grammar (MSSG) was presented along with preliminary normative information. MSSG analyses leverage the strong psychometrics and rich procedural knowledge of both main concept analysis and story grammar component coding, complementing it with easy-to-obtain sequencing information for a rich understanding of discourse informativeness and macrostructure. This study is the next critical step for demonstrating the clinical usefulness of MSSG’s six variables (main concept composite, sequencing, main concept+sequencing, essential story grammar components, total episodic components, and episodic complexity) for persons with aphasia (PWAs). We present descriptive statistical information for MSSG variables for a large sample of PWAs and compare their performance to a large sample of persons not brain injured (PNBIs). We observed significant differences between PWAs and PNBIs for all MSSG variables. These differences occurred at the omnibus group level and for each aphasia subtype, even for PWAs with very mild impairment that is not detected with standardized aphasia assessment. Differences between PWAs and PNBIs were also practically significant, with medium to large effect sizes observed for nearly all aphasia subtypes and MSSG variables. This work deepens our understanding of discourse informativeness and macrostructure in PWAs and further develops an efficient tool for research and clinical use. Future research should investigate ways to expand MSSG analyses and to improve sensitivity and specificity.

Relationship between Cognitive Reserve and Cognitive Impairment in Autonomous and Institutionalized Older Adults

It is necessary to determine which variables help prevent the presence of decline or deterioration during the aging process as a function of advancing age. This research analyses the relations between cognitive reserve (CR) and cognitive impairment in 300 individuals. It also aims to confirm the influence of different variables (gender, age, level of studies and institutionalization) in CR and in deterioration in a population of older adults. The results indicate that people with higher CR present less deterioration. Regarding the role of the sociodemographic variables in the level of deterioration and CR, there are no differences between men and women, but there are differences in the variables age, level of studies and institutionalization, in such a way that the older age the greater the cognitive deterioration, the higher the level of studies, the more RC and less deterioration and it was found that the non-institutionalized people present less deterioration and greater CR. It is affirmed that two people with similar clinical characteristics may present different levels of pathology, being the CR the explanation of this fact. The results obtained allow us to affirm that the measurement of CR is considered an essential variable for the diagnosis of neurodegenerative diseases.

Feasibility of an integrated multidisciplinary geriatric rehabilitation programme for older stroke patients: a process evaluation

Background

Almost half of the stroke patients admitted to geriatric rehabilitation has persisting problems after discharge. Currently, there is no evidence based geriatric rehabilitation programme available for older stroke patients, combining inpatient rehabilitation with adequate aftercare aimed at reducing the impact of persisting problems after discharge from a geriatric rehabilitation unit. Therefore, we developed an integrated multidisciplinary rehabilitation programme consisting of inpatient neurorehabilitation treatment using goal attainment scaling, home based self-management training, and group based stroke education for patients and informal caregivers. We performed a process evaluation to assess to what extent this programme was performed according to protocol. Furthermore, we assessed the participation of the patients in the programme, and the opinion of patients, informal caregivers and care professionals on the programme.

Methods

In this multimethod study, process data were collected by means of interviews, questionnaires, and registration forms among 97 older stroke patients, 89 informal caregivers, and 103 care professionals involved in the programme.

Results

A part of patients and informal caregivers did not receive all key elements of the programme. Almost all patients formulated rehabilitation goals, but among two thirds of the patients the goal attainment scaling method was used. Furthermore, the self-management training was considered rather complex and difficult to apply for frail elderly persons with stroke, and the percentage of therapy sessions performed in the patients’ home environment was lower than planned. In addition, about a quarter of the patients and informal caregivers attended the education sessions. However, a majority of patients, informal caregivers and care professionals indicated the beneficial aspects of the programme.

Conclusion

This study revealed that although the programme in general is perceived to be beneficial by patients, and informal and formal caregivers, the feasibility of the programme needs further attention. Because of persisting cognitive deficits and specific care needs in our frail and multimorbid target population, some widely used methods such as goal attainment scaling, and self-management training seemed not feasible in their current form. To optimize feasibility of the programme, it is recommended to tailor these elements more optimally to the population of frail older patients.