Cognitive impairment after stroke is common and can cause disability with major impacts on quality of life and independence. There are also indirect effects of cognitive impairment on functional ...recovery after stroke through reduced participation in rehabilitation and poor adherence to treatment guidelines. In this article, we attempt to establish the following: • whether there is a distinct profile of cognitive impairment after stroke; • whether the type of cognitive deficit can be associated with the features of stroke-related damage; and • whether interventions can improve poststroke cognitive performance. There is not a consistent profile of cognitive deficits in stroke, though slowed information processing and executive dysfunction tend to predominate. Our understanding of structure-function relationships has been advanced using imaging techniques such as lesion mapping and will be further enhanced through better characterization of damage to functional networks and identification of subtle white matter abnormalities. Effective cognitive rehabilitation approaches have been reported for focal cortical deficits such as neglect and aphasia, but treatments for more diffusely represented cognitive impairment remain elusive. In the future, the hope is that different techniques that have been shown to promote neural plasticity (e.g., exercise, brain stimulation, and pharmacological agents) can be applied to improve the cognitive function of stroke survivors.
Language recovery following stroke Gerstenecker, Adam; Lazar, Ronald M.
Clinical neuropsychologist,
07/2019, Letnik:
33, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Objective: To review the research literature pertaining to post-stroke language recovery, and to discuss neurocognitive assessment in patients in the context of aphasia, time course of language ...recovery, factors associated with language recovery, and therapeutic techniques designed to facilitate language recovery.
Method: Articles were identified through PubMed, MEDLINE, PsychINFO, and Google Scholar searches. Examples of utilized keywords include "post-stroke aphasia," "post-stroke language recovery," "post-stroke neurocognitive assessment," and "neuropsychology and aphasia."
Results: Most language recovery occurs in the first few weeks following stroke, but residual recovery may occur for many years. Although initial aphasia severity is the single largest determinant of post-stroke language recovery, a number of other variables also contribute. Several techniques have been developed to aid in the recovery process including speech-language therapy and noninvasive brain stimulation, although the effectiveness of acute and subacute treatment remains unclear. Some degree of valid neurocognitive assessment is possible in patients with aphasia, and the information gained from such an evaluation can aid the rehabilitative process
Conclusions: Significant recovery of language function is possible following a stroke, but prediction of level of recovery in an individual patient is difficult. Information about initial aphasia severity and the integrity of cognitive domains other than language can help guide the rehabilitation team, as well as manage expectations for recovery.
Cortical thinning is a potentially important biomarker, but the pathophysiology in cerebrovascular disease is unknown. We investigated the association between regional cortical blood flow and ...regional cortical thickness in patients with asymptomatic unilateral high-grade internal carotid artery disease without stroke. Twenty-nine patients underwent high resolution anatomical and single-delay, pseudocontinuous arterial spin labeling magnetic resonance imaging with partial volume correction to assess gray matter baseline flow. Cortical thickness was estimated using Freesurfer software, followed by co-registration onto each patient's cerebral blood flow image space. Paired t-tests assessed regional cerebral blood flow in motor cortex (supplied by the carotid artery) and visual cortex (indirectly supplied by the carotid) on the occluded and unoccluded side. Pearson correlations were calculated between cortical thickness and regional cerebral blood flow, along with age, hypertension, diabetes and white matter hyperintensity volume. Multiple regression and generalized estimating equation were used to predict cortical thickness bilaterally and in each hemisphere separately. Cortical blood flow correlated with thickness in motor cortex bilaterally (p = 0.0002), and in the occluded and unoccluded sides individually; age (p = 0.002) was also a predictor of cortical thickness in the motor cortex. None of the variables predicted cortical thickness in visual cortex. Blood flow was significantly lower on the occluded versus unoccluded side in the motor cortex (p<0.0001) and in the visual cortex (p = 0.018). On average, cortex was thinner on the side of occlusion in motor but not in visual cortex. The association between cortical blood flow and cortical thickness in carotid arterial territory with greater thinning on the side of the carotid occlusion suggests that altered cerebral hemodynamics is a factor in cortical thinning.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Clinical interpretation of arterial spin labeling (ASL) perfusion MRI in cerebrovascular disease remains challenging mainly because of the method's sensitivity to concomitant contributions from both ...intravascular and tissue compartments. While acquisition of multi-delay images can differentiate between the two contributions, the prolonged acquisition is prone to artifacts and not practical for clinical applications. Here, the utility of the spatial coefficient of variation (sCoV) of a single-delay ASL image as a marker of the intravascular contribution was evaluated by testing the hypothesis that sCoV can detect the effects of differences in label arrival times between ipsi- and contra-lateral hemispheres even in the absence of a hemispheric difference in CBF. Hemispheric lateralization values for sCoV and CBF were computed from ASL images acquired on 28 patients (age 73.9 ± 10.2 years, 8 women) with asymptomatic unilateral carotid occlusion. The results showed that sCoV lateralization predicted the occluded side with 96.4% sensitivity, missing only 1 patient. In contrast, the sensitivity of the CBF lateralization was 71.4%, with 8 patients showing no difference in CBF between hemispheres. The findings demonstrate the potential clinical utility of sCoV as a cerebrovascular correlate of large vessel disease. Using sCoV in tandem with CBF, vascular information can be obtained in image processing without the need for additional scan-time.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Rationale
Trials conducted decades ago demonstrated that carotid endarterectomy by skilled surgeons reduced stroke risk in asymptomatic patients. Developments in carotid stenting and improvements in ...medical prevention of stroke caused by atherothrombotic disease challenge understanding of the benefits of revascularization.
Aim
Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial (CREST-2) will test whether carotid endarterectomy or carotid stenting plus contemporary intensive medical therapy is superior to intensive medical therapy alone in the primary prevention of stroke in patients with high-grade asymptomatic carotid stenosis.
Methods and design
CREST-2 is two multicenter randomized trials of revascularization plus intensive medical therapy versus intensive medical therapy alone. One trial randomizes patients to carotid endarterectomy plus intensive medical therapy versus intensive medical therapy alone; the other, to carotid stenting plus intensive medical therapy versus intensive medical therapy alone. The risk factor targets of centrally directed intensive medical therapy are LDL cholesterol <70 mg/dl and systolic blood pressure <140 mmHg.
Study outcomes
The primary outcome is the composite of stroke and death within 44 days following randomization and stroke ipsilateral to the target vessel thereafter, up to four years. Change in cognition and differences in major and minor stroke are secondary outcomes.
Sample size
Enrollment of 1240 patients in each trial provides 85% power to detect a treatment difference if the event rate in the intensive medical therapy alone arm is 4.8% higher or 2.8% lower than an anticipated 3.6% rate in the revascularization arm.
Discussion
Management of asymptomatic carotid stenosis requires contemporary randomized trials to address whether carotid endarterectomy or carotid stenting plus intensive medical therapy is superior in preventing stroke beyond intensive medical therapy alone. Whether carotid endarterectomy or carotid stenting has favorable effects on cognition will also be tested.
Trial registration
United States National Institutes of Health Clinicaltrials.gov NCT02089217
Most improvement from poststroke aphasia occurs within the first 3 months, but there remains unexplained variability in recovery. Recently, we reported a strong correlation between initial impairment ...and change scores in motor recovery at 90 days. We wanted to determine whether aphasia recovery (defined as a change from baseline to 90 days) shows a comparably strong correlation and whether the relation was similar to that in motor recovery.
Twenty-one stroke patients had aphasia scores on the Western Aphasia Battery (WAB) obtained on stroke admission (WAB(initial)) and at 90 days (WAB(3 mo)). The relation between actual change (Delta) scores (defined as WAB(3 mo)- WAB(initial)) and WAB(initial) was calculated in multiple-regression analysis.
Regression analysis demonstrated that WAB(initial) was highly correlated with DeltaWAB (R(2)=0.81, P<0.001) and that, in addition, the relation between WAB(initial) and DeltaWAB was proportional, such that patients recovered 0.73 of maximal potential recovery (WAB(maximum)-WAB(initial)).
We show that, like motor recovery, there is a highly predictable relation between aphasia recovery and initial impairment, which is also proportional in nature. The comparability of recovery from motor and language impairment suggests that common mechanisms may govern reduction of poststroke neurologic impairment across different functional domains and that they could be the focus of therapeutic intervention.
Aphasia As a Predictor of Stroke Outcome Lazar, Ronald M.; Boehme, Amelia K.
Current neurology and neuroscience reports,
11/2017, Letnik:
17, Številka:
11
Journal Article
Recenzirano
Purpose of Review
Aphasia is a common feature of stroke, affecting 21–38% of acute stroke patients and an estimated 1 million stroke survivors. Although stroke, as a syndrome, is the leading cause of ...disability in the USA, less is known about the independent impact of aphasia on stroke outcomes.
Recent Findings
During the acute stroke period, aphasia has been found to increase length of stay, inpatient complications, overall neurological disability, mortality, and to alter discharge disposition. Outcomes during the sub-acute and chronic stroke periods show that aphasia is associated with lower Functional Independence Measures (FIM) scores, longer stays in rehabilitation settings, poorer function in activities of daily living, and mortality. Factors that complicate the analysis of aphasia on post-stroke outcomes, however, include widely different systems of care across international settings that result in varying admission patterns to acute stroke units, allowable length of stays based on reimbursement, and criteria for rehabilitation placement.
Summary
Aphasia arising from stroke is associated with worse outcomes both in the acute and chronic periods. Future research will have to incorporate disparate patterns in analytic models, and to take into account specific aphasia profiles and evolving methods of post-stroke speech-language therapy.
Silent brain infarctions (SBIs) are brain lesions noted on neuroimaging that are not associated with clinical symptoms. SBIs are associated with a number of vascular risk factors and are common ...following invasive cardiovascular procedures such as atrial fibrillation (AF) ablation, coronary artery bypass graft (CABG), and transcatheter aortic valve replacement (TAVR). Although not eliciting signs of clinical stroke, SBIs are associated with increased frailty, and motor and mood features. Less is known, however, about the relationship between SBI, cognition, and delirium following invasive cardiac procedures and most investigations into these relationships have been reported in large-scale epidemiological studies. In the current paper, we conducted a systematic review to evaluate evidence of a relationship between SBI, delirium, and cognitive decline following CABG, AF ablation, and TAVR. Twenty studies met inclusion criteria. In general, our review identified conflicting results for each cardiac procedure, with some studies suggesting a relationship between SBI, cognitive impairment, and delirium, whereas others showed no relationship between SBI, cognitive impairment, and delirium. Potential reasons for this discrepancy as well as suggestions for future research are discussed.
The physiological effects of retinoic acids (RAs) are mediated by members of two families of nuclear receptors, the retinoic acid receptors (RARs) and the retinoid X receptors (RXRs), which are ...encoded by three distinct human genes, RXRalpha, RXRbeta, and RXRgamma. RARs bind both all-trans- and 9-cis-RA, whereas only the 9-cis-RA stereoisomer binds to RXRs. As RXR/RAR heterodimers, these receptors control the transcription of RA target genes through binding to RA-response elements. This review is focused on the structure, mode of action, ligands, expression, and pharmacology of RXRs. Given their role as common partners to many other members of the nuclear receptor superfamily, these receptors have been the subject of intense scrutiny. Moreover, and despite numerous studies since their initial discovery, RXRs remain enigmatic nuclear receptors, and there is still no consensus regarding their role. Indeed, multiple questions about the actual biological role of RXRs and the existence of an endogenous ligand have still to be answered.
Along with the rising burden of peripheral artery disease (PAD), mental health concerns are increasingly being recognized as a comorbidity to address in the chronic disease management of symptomatic ...PAD. Apart from a high prevalence of comorbid mental health conditions, the role of pain and changing health behaviors and the broader impacts of illness and adaptation to living with PAD require specialized behavioral health expertise. This scientific statement builds a case that this expertise should be integrated within the multidisciplinary PAD team. Furthermore, areas such as cognitive dysfunction and palliative care are highlighted as needing psychological interventions. Although much of the evidence of the efficacy of psychological and psychotropic interventions has been extrapolated from other cardiovascular populations, evidence for the role of psychological interventions for behavior change, for example, uptake of exercise regimens, is increasingly being accrued within PAD. Areas for behavioral health needs and interactions with PAD treatment are discussed, including the use of opioids, depression management, anxiety and stress reduction interventions, the use of benzodiazepines and antidepressants, smoking cessation, rehabilitation trajectories after amputation, and the role of cognitive decline for PAD treatment and outcomes. A case summary highlights the stigma around mental health and vascular disease and the fragmentation of care. This scientific statement provides remarks for building a road map for integrated behavioral PAD care and potential solutions to overcome these barriers. Instrumental to reaching these changes are interprofessional advocacy efforts and initiatives that help break down the stigma around mental health and promote evidence-based collaborative, nonhierarchical, and multidisciplinary PAD care.