Executive functioning as a predictor of stroke rehabilitation outcomes

Intraindividual variability in post-stroke cognition and its relationship with activities of daily living and social functioning: an ecological momentary assessment approach

INTRODUCTION

Ecological momentary assessment (EMA) is a methodological approach to studying intraindividual variation over time. This study aimed to use EMA to determine the variability of cognition in individuals with chronic stroke, identify the latent classes of cognitive variability, and examine any differences in daily activities, social functioning, and neuropsychological performance between these latent classes.

METHODS

Participants (N = 202) with mild-to-moderate stroke and over 3-month post-stroke completed a study protocol, including smartphone-based EMA and two lab visits. Participants responded to five EMA surveys daily for 14 days to assess cognition. They completed patient-reported measures and neuropsychological assessments during lab visits. Using latent class analysis, we derived four indicators to quantify cognitive variability and identified latent classes among participants. We used ANOVA and Chi-square to test differences between these latent classes in daily activities, social functioning, and neuropsychological performance.

RESULTS

The latent class analysis converged on a three-class model. The moderate and high variability classes demonstrated significantly greater problems in daily activities and social functioning than the low class. They had significantly higher proportions of participants with problems in daily activities and social functioning than the low class. Neuropsychological performance was not statistically different between the three classes, although a trend approaching statistically significant difference was observed in working memory and executive function domains.

DISCUSSION

EMA could capture intraindividual cognitive variability in stroke survivors. It offers a new approach to understanding the impact and mechanism of post-stroke cognitive problems in daily life and identifying individuals benefiting from self-regulation interventions.

Validity of the Chinese version of the weekly calendar planning activity (WCPA) on assessing executive function in adults with stroke

The weekly calendar planning activity (WCPA) is a performance-based assessment of executive function (EF) via a cognitively-based instrumental activity of daily life (C-IADL). This study aimed to examine the validity of the Chinese version of the WCPA in adults with stroke and to explore the characteristics of cognitive strategy use among the population. Fifty-eight hospitalized patients with stroke aged 26-82 years and 53 controls completed the WCPA, two neuropsychological tests and instrumental activity of daily life (IADL) scale. Participants with stroke were subdivided into a stroke cognitive impaired group (Stroke-CI) and a general stroke group (Stroke-NCI) based on the Montreal Cognitive Assessment. Results showed that the WCPA was able to discriminate between Stroke-CI with controls and the Stroke-NCI group with controls. We found significant limitations in stroke patients' ability to use strategies. Concurrent and ecological validities were demonstrated through correlations between the neuropsychological test scores, IADL and the WCPA performance. This study provides initial evidence for the validity of the Chinese version of the WCPA-10 for adults with stroke and suggests the need to use performance-based tests even in patients with normal cognitive screening test results. The WCPA could provide useful information for strategy-based interventions for adults with stroke.

Poorer Inhibitory Control Uniquely Contributes to Greater Functional Disability in Post-9/11 Veterans

OBJECTIVE

Post-9/11 Veterans endorse greater self-reported functional disability than 80% of the adult population. Previous studies of trauma-exposed populations have shown that increased post-traumatic stress disorder (PTSD) and depressive symptoms are consistently associated with greater disability. Additionally, poorer cognitive performance in the domain of executive functions, particularly inhibitory control, has been associated with disability, though it is unclear if this effect is independent of and/or interacts with PTSD and depression.

METHOD

Three overlapping samples of n = 582, 297, and 183 combat-deployed post-9/11 Veterans completed comprehensive assessments of executive functions, PTSD and depressive symptoms, and self-reported World Health Organization Disability Assessment Schedule-II (WHODAS II).

RESULTS

Poorer performance on measures of inhibitory control (Delis-Kaplan Executive Functioning System Color-Word Interference-CWI Test and gradual-onset Continuous Performance Test-gradCPT), but not other executive functions, were significantly associated with greater disability on the WHODAS II (ρ's = -.13 and -.13, p = .002 and .026, respectively). CWI inhibitory control measures accounted for unique variance in disability after controlling for PTSD and depressive symptoms (R2 change = 0.02, p < .001). Further, CWI significantly moderated the effect of depressive symptoms on disability, such that better inhibitory control weakened the relationship between depression and disability.

CONCLUSIONS

Inhibitory control deficits are uniquely associated with increased disability in combat-deployed post-9/11 Veterans, and better inhibitory control abilities may serve as a protective factor for depressive symptoms leading to increased disability.

KEY POINTS

Does Executive Function Training Impact on Communication? A Randomized Controlled tDCS Study on Post-Stroke Aphasia

New approaches in aphasia rehabilitation have recently identified the crucial role of executive functions (EFs) in language recovery, especially for people with severe aphasia (PWSA). Indeed, EFs include high-order cognitive abilities such as planning and problem solving, which enable humans to adapt to novel situations and are essential for everyday functional communication. In a randomized double-blind crossover design, twenty chronic Italian PWSA underwent ten days of transcranial direct current stimulation (tDCS) (20 min, 2 mA) over the right dorsolateral prefrontal cortex (DLPFC). Two conditions were considered, i.e., anodal and sham, while performing four types of cognitive training (alertness, selective attention, visuo-spatial working memory, and planning), all of which were related to executive functions. After anodal tDCS, a greater improvement in selective attention, visuospatial working memory and planning abilities was found compared to the sham condition; this improvement persisted one month after the intervention. Importantly, a significant improvement was also observed in functional communication, as measured through the Communication Activities of Daily Living Scale, in noun and verb naming, in auditory and written language comprehension tasks and in executive function abilities. This evidence emphasizes, for the first time, that tDCS over the right DLPFC combined with executive training enhances functional communication in severe aphasia.

Discharge Rehabilitation Measures Predict Activity Limitations in Patients With Stroke 6 Months After Inpatient Rehabilitation

OBJECTIVE

The aim of this study was to identify rehabilitation measures at discharge from acute inpatient stroke rehabilitation that predict activity limitations at 6 mos postdischarge.

DESIGN

This is a retrospective analysis of a prospective, longitudinal, observational cohort study. It was conducted in an acute inpatient rehabilitation unit at an urban, academic medical center. Activity limitations in patients ( N = 141) with stroke of mild-moderate severity were assessed with the activity measure for post-acute care at inpatient stroke rehabilitation discharge and 6-mo follow-up. Rehabilitation measures at discharge were investigated as predictors for activity limitations at 6 mos.

RESULTS

Measures of balance (Berg Balance Scale), functional limitations in motor-based activities (functional independence measure-motor subscore), and motor impairment (motricity index), in addition to discharge activities measure for post-acute care scores, strongly predicted activity limitations in basic mobility and daily activities at 6 mos (51% and 41% variance explained, respectively). Functional limitations in cognition (functional independence measure-cognitive subscore) and executive function impairment (Trail Making Test-part B), in addition to the discharge activities measure for post-acute care score, modestly predicted limitations in cognitively based daily activities at 6 mos (12% of variance).

CONCLUSIONS

Standardized rehabilitation measures at inpatient stroke rehabilitation discharge can predict future activity limitations, which may improve prediction of outcome post-stroke and aid in postdischarge treatment planning.

Determinants of Disability at 6 Months After Stroke: the GRECogVASC Study

BACKGROUND

The present study aimed at determining the contributions of background disorders responsible for participation restriction as indexed by a structured interview for the modified Rankin scale (mRS-SI).

METHODS

A subset of 256 patients was assessed at 6 months after stroke using the National Institutes of Health Stroke Scale (NIHSS), gait score, comprehensive cognitive battery (yielding a global cognitive Z-score), behavioral dysexecutive disorders (DDs), anxiety and depressive symptoms, epilepsy, and headache. Following bivariate analyses, determinants of participation restriction were selected using ordinal regression analysis with partial odds.

RESULTS

Poststroke participation restriction (mRS-SI >1) was observed in 59% of the patients. In bivariate analyses mRS-SI was associated with prestroke mRS-SI, 6-month NIHSS score, gait score, global cognitive Z-score, behavioral DDs, and presence of anxiety and depression (p=0.0001, all) (epilepsy: p=0.3; headache: p=0.7). After logistic regression analysis, the NIHSS score was associated with increasing mRS-SI grades (p=0.00001). Prestroke mRS-SI (p=0.00001), behavioral DDs (p=0.0008) and global cognitive Z-score (p=0.01) were associated with both mRS-SI>1 and mRS-SI>2. In addition, the gait score was associated with mRS-SI >2 (p=0.00001). This model classified 85% of mRS-SI correctly (p=0.001). Structural equation modeling showed the contributions of gait limitation (standardized coefficient (SC): 0.68, p=0.01), prestroke mRS-SI (SC: 0.41, p=0.01), severity of neurological impairment (SC: 0.16, p=0.01), global cognitive Z-score (SC: -0.14, p=0.05), and behavioral DDs (SC: 0.13, p=0.01).

CONCLUSION

These results provide a statistical model of weights of determinants responsible for poststroke participation restriction and highlight a new independent determinant: behavioral DDs.

The Structural and Functional Neuroanatomy of Post-Stroke Depression and Executive Dysfunction: A Review of Neuroimaging Findings and Implications for Treatment

Post-stroke depression and executive dysfunction co-occur and are highly debilitating. Few treatments alleviate both depression and executive dysfunction after stroke. Understanding the brain network changes underlying post-stroke depression with executive dysfunction can inform the development of targeted and efficacious treatment. In this review, we synthesize neuroimaging findings in post-stroke depression and post-stroke executive dysfunction and highlight the network commonalities that may underlie this comorbidity. Structural and functional alterations in the cognitive control network, salience network, and default mode network are associated with depression and executive dysfunction after stroke. Specifically, post-stroke depression and executive dysfunction are both linked to changes in intrinsic functional connectivity within resting state networks, functional over-connectivity between the default mode and salience/cognitive control networks, and reduced cross-hemispheric frontoparietal functional connectivity. Cognitive training and noninvasive brain stimulation targeted at these brain network abnormalities and specific clinical phenotypes may help advance treatment for post-stroke depression with executive dysfunction.

What do people respond to when rating executive function? - a cognitive interviewing investigation of BRIEF-A informant ratings in severe aphasia

PURPOSE

Executive dysfunction is common in persons with severe aphasia. Assessing these functions in this population is challenging. Informant ratings, such as the BRIEF-A, might be a useful alternative to neuropsychological tests. However, research has shown weak relationships between tests and ratings. The aim of this study was to understand how significant others of people with severe aphasia interpret and respond to questions about executive function in the informant report version of BRIEF-A.

METHODS

Eleven significant others were interviewed about a subset of the BRIEF-A items, using cognitive interviewing. Interviews were subjected to thematic analysis.

RESULTS

There was variation in the interpretation of the items of BRIEF-A which frequently corrupted the items' relation to what it was intended to measure. Further, informants wavered between considering the person with aphasias' ability or actual performance and many had lowered their expectations. The language problems caused by the aphasia affected the validity of some items.

CONCLUSIONS

The quantitative results of BRIEF-A informant ratings should be interpreted with caution, since it is unclear to what extent the responses represent executive function. The use of informant ratings does not solve the problem with aphasia being a confounding factor in assessment of executive function.IMPLICATIONS FOR REHABILITATIONAssessing executive function in people with severe aphasia is important but challenging.Quantitative results of informant ratings of executive function, such as BRIEF-A, in this population should be interpreted with caution, since it is unclear to what extent the ratings represent executive function.Using informant ratings does not solve the problem of the aphasia being a confounding factor, since the aphasia impacts on the validity of some of the items.

Executive Functions Are Associated with Fall Risk but not Balance in Chronic Cerebrovascular Disease

BACKGROUND

Older people's deficits in executive functions (EF) have been shown to lead to higher fall risk, postural sway, and reduced speed. Crucially, EF impairments are even more pronounced in individuals with chronic cerebrovascular disease (CVD), namely vascular cognitive impairment.

METHODS

In this retrospective cross-sectional study, we used a complete neuropsychological battery, including the Trail Making Test (TMT) and physical measures, such as the Morse fall and EQUI scales, to assess 66 individuals with chronic CVD. Linear regressions, Bayesian analyses, and model selection were performed to see the impact of EF, global cognition, and vascular parkinsonism/hemiplegia on physical measures (fall risk and balance).

RESULTS

The TMT part B and BA correlated (r = 0.44 and r = 0.45) with Morse fall scale. Only EF significantly explained fall risk, whereas global cognition and vascular parkinsonism/hemiplegia did not. These findings were confirmed by Bayesian evidence and parsimony model selection. Balance was not significantly correlated with any of the neuropsychological tests.

CONCLUSIONS

This is the first study investigating the relationship between cognitive and physical measures in a sample of older people with chronic CVD. The results are consistent with previous findings that link EF with fall risk in CVD.

The Association Between an Antecedent of Transient Ischemic Attack Prior to Onset of Stroke and Functional Ambulatory Outcome

BACKGROUND

Specific clinical risk factors linked to transient ischemic attack (TIA) could affect functional ambulatory outcome following thrombolytic therapy in patients having ischemic stroke with a prior TIA (TIA-ischemic stroke). This issue was investigated in this study.

METHODS

We retrospectively analyzed data from 6379 ischemic stroke patients of which 1387 presented with an antecedent TIA prior to onset of stroke. We used logistic regression model to identify demographic and clinical risk factors that are associated with functional ambulatory outcome in patients with TIA-ischemic stroke treated with thrombolytic therapy.

RESULTS

In a population of TIA-ischemic stroke who received recombinant tissue plasminogen activator, patients with a history of stroke (odds ratio [OR] = 3.229, 95% confidence interval [CI] = 1.494-6.98, P = .003) were associated with increasing odds of improvement in functional ambulation, while the female gender (OR = 0.462, 95% CI = 0.223-0.956, P = .037) was associated with reducing odds of improvement. In the non-TIA group, dyslipidemia (OR = 1.351, 95% CI = 1.026-1.781, P = .032) and blood glucose (OR = 1.003, 95% CI = 1.0-1.005, P = .041) were associated with the increasing odds of improvement while older patients (OR = 0.989, 95% CI = 0.98-0.999, P = .029) with heart failure (OR = 0.513, 95% CI = 0.326-0.808, P = .004) and higher lipid level (OR = 0.834, 95% CI = 0.728-0.955, P = .009) were associated with reducing odds of improvement in ambulation.

CONCLUSION

In a population of TIA-ischemic stroke with thrombolytic therapy and a clearly defined TIA without focal ischemic injury, regardless of associated clinical risk factors, a TIA prior to a stroke is not associated with reducing odds of improved ambulatory outcome, except in female patients with TIA-ischemic stroke.

Assessment of cognitive instrumental activities of daily living: a systematic review

PURPOSE

Cognitive instrumental activities of daily living are particularly related to executive functions, such as scheduling appointments, monthly payments, managing the household economy, shopping or taking the bus. The aim of this systematic review was to determine the available tests for the assessment of executive functions with ecological validity to predict individuals' functioning.

MATERIALS AND METHODS

An electronic search was conducted in MEDLINE, Cochrane Central, PsyCInfo and IEEE Xplore until May 2019, in addition to a manual search. The PRISMA criteria and the Covidence platform were used to select articles and extract data.

RESULTS

After applying the search selection criteria, 76 studies were identified. They referred to 110 tools to assess instrumental activities of daily living. Those that have received most attention are related to menu preparation and shopping. Performance-based measures are the most widely used traditional methods. Most tests were aimed at the adult population with acquired brain damage, cognitive impairment or dementia. There was a predominance of tests based on the Multiple Errands Test paradigm.

CONCLUSIONS

In recent years, it has increased the number of tools that assess the instrumental activities of daily living based on technologies such as personal or environmental sensors and serious games.IMPLICATIONS FOR REHABILITATIONAssessment of Instrumental Activities of Daily Living through performance-based measures is especially useful for the early detection of dysfunctions or preclinical disability.Difficulties in performing instrumental activities of daily living are closely associated with deficits in executive functions and prospective memory.Activities of Daily Living can be understood as multitasks.The use of virtual reality-based tests was shown to be sensitive to the detection of cognitive deficits in Activities of Daily Living.An advantage of using virtual reality in assessments is that it can help to predict the level of personal autonomy in patients who are in an institutional environment and could be a first approximation to the real environment.

Recovery from stroke: factors affecting prognosis

Objective: Stroke is commonly seen in neuropsychological practice. Individual differences, diffuse damage, and the difficulty inherent in researching stroke create challenges for the clinician trying to synthesize the latest information to educate patients and families on prognosis. The objective of this special issue is to provide an overview of the latest clinical research in stroke - the contributors address assessment and treatment issues that are relevant to practice. Method: We solicited papers from established researchers and issued a general call for papers for the special issue on stroke. Results: We received submissions from several authors, eight of which are included in this issue. These submissions cover both assessment and treatment issues and include two review articles, one on language and one on spatial neglect. Two apparent themes are the utility of early assessment/treatment and the importance of executive functioning in predicting later functioning. Conclusions: The issue highlights the need for clinical neuropsychologists to be aware of the latest research on recovery from stroke and the importance of both assessment and management strategies to reduce impact on daily life.