Post-stroke Cognitive Impairment Patients Research Articles

Lower serum BDNF as a predictor of post-stroke cognitive impairment in acute ischemic stroke patients

Background Reduced level of serum brain-derived neurotrophic factor (BDNF) in acute stroke patients is associated with poor outcomes. We aimed to identify the role of serum BDNF level as a predictor for post-stroke cognitive impairment (PSCI). Methods This was a prospective study. We recruited acute ischemic stroke patients in Dr. Sardjito General Hospital Yogyakarta, Indonesia followed them up for 90 days (3 months). Serum BDNF was collected at day 5 and day 30 of stroke onset and measured by enzyme-linked immunosorbent assay (ELISA). Montreal Cognitive Assessment (MoCA) was used to measure the cognitive function at 90 days of follow up. Receiver operating characteristic (ROC) curve was conducted to measure the cut-off point of the BDNF level. Factors independently associated with PSCI were analyzed by using stepwise regression. Results Among 89 patients recruited, 60 patients (67.41%) developed PSCI. The mean age of PSCI and non-PSCI patients was 62.7 ± 9.5 and 57.5 ± 8.7, respectively (p = 0.01). Patients with dyslipidemia were less likely to develop PSCI (OR 0.10, 95%CI 0.02-0.51, p < 0.05). In addition, patients with day 5-serum BDNF level < 23.29 ng/mL were five times more likely to develop PSCI compared with their counterparts (OR 5.15, 95%CI 1.26-21.09, p < 0.05). Conclusions Among acute ischemic stroke patients, those with serum BDNF <23.29 ng/mL had a higher risk of developing PSCI. This study suggests that BDNF could be a predictor of PSCI, allowing for earlier detection and better preventive strategies.

Utilizing fNIRS to investigate the impact of Baduanjin training on attentional function in post-stroke cognitive impairment patients: a study protocol for a randomized controlled trial

BackgroundPost-stroke cognitive impairment (PSCI) is a prevalent complication among stroke survivors. It not only directly impacts patients' cognitive abilities but also hampers their capacity to regain independence in daily activities, consequently diminishing their quality of life. Among the various cognitive deficits following stroke, impaired attention is the most frequently observed, influencing not only daily functioning but also higher cognitive functions like working memory, executive functioning, and language.Emerging evidence indicates that Baduanjin, a traditional Chinese exercise, may have a positive impact on enhancing attention in older adults with mild cognitive impairment and stroke survivors. However, the precise mechanisms behind this effect remain unclear. In this study, we employed Baduanjin training as an intervention to address attention decline in post-stroke cognitive impairment patients and to delve into the potential mechanisms through which Baduanjin training may enhance attention in individuals with PSCI.MethodsIn this prospective randomized controlled trial, we plan to recruit 72 participants diagnosed with post-stroke cognitive impairment (PSCI). These participants will be randomly assigned in a 1:1:1 ratio to one of three groups: Baduanjin training(left hemisphere stroke and right hemisphere stroke) and conventional treatment.The conventional treatment group will receive standard rehabilitation sessions. In addition to conventional treatment, participants in the octogenarian training groups will undergo octogenarian training sessions lasting 40 min, five times a week, over a total period of 12 weeks.The primary outcome measures will include the Montreal Cognitive Assessment (MoCA) scale and the Attentional Lateralization Index. These assessments will be conducted by a trained evaluator before the start of the intervention and at weeks 6 and 12 after the intervention begins.Secondary outcome measures will be assessed using the baseline Mandarin version of the Oxford Cognitive Screening (OCS-P) scale, the simplified Fugl-Meyer Motor Function Assessment (FMA) scale, the Pittsburgh Rehabilitation Participation (PRPS) scale, and the Activities of Daily Living (ADL) scale before and after the intervention, respectively.DiscussionThis trial aims to examine the impact of Baduanjin training on attentional lateralization among patients with post-stroke cognitive impairment (PSCI). Functional brain imaging utilizing near-infrared spectroscopy will be employed to investigate how Baduanjin exercise influences the structural and functional connectivity of distinct brain regions or brain networks.Trial registrationChictr.org.cn, ID: ChiCTR2300076533. Registered on 11 October 2023.

Differentially Expressed miR-511-3p in Stroke Patients Predicts the Presence of Post-Stroke Cognitive Impairment.

Stroke is common cerebrovascular disease in the elderly, which is characterized by neurological defects caused by cerebral vessels. Multiple studies have shown that miRNAs play important roles in stroke. In addition, a large number of evidence suggest that stroke increases the risk and severity of cognitive impairments. miR-511-3p expression levels were detected by real-time PCR. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic value of miR-511-3p in distinguishing stroke patients from healthy controls and to assess risk of post-stroke cognitive impairment (PSCI) in stroke patients. Pearson correlation coefficient was used to determine the relationship between miR-511-3p expression level and Montreal Cognitive Assessment Scale (MoCA) scores. Serum miR-511-3p expression levels were decreased in stroke patients, and the decrease was more significant in PSCI patients. ROC curve results showed that miR-511-3p had high diagnostic accuracy in distinguishing healthy controls from stroke patients. Moreover, the expression level of miR-511-3p can be used as an independent predictor for the occurrence of PSCI and is positively correlated with MoCA scores of PSCI patients. miR-511-3p may be involved in the occurrence and development of stroke. In addition, miR-511-3p may be a novel biomarker for predicting PSCI occurred in stroke patients. These results may help improve the quality of prognosis of stroke.

Genetic Variations and Altered Blood mRNA Level of Circadian Genes and BDNF as Risk Factors of Post-Stroke Cognitive Impairment Among Eastern Indians.

Post-stroke cognitive impairment (PSCI) is a clinical outcome in around 30% of post-stroke survivors. BDNF is a major gene in this regard. It is regulated by circadian rhythm. The circadian genes are correlated with stroke timings at molecular level. However, studies suggesting the role of these on susceptibility to PSCI are limited. We aim here to determine: (a) genetic risk variants in circadian clock genes, BDNF and (b) dysregulation in expression level of CLOCK, BMAL1, and BDNF that may be associated with PSCI. BDNF (rs6265G/A, rs56164415C/T), CLOCK (rs1801260T/C, rs4580704G/C), and CRY2 (rs2292912C/G) genes variants were genotyped among 119 post-stroke survivors and 292 controls from Eastern part of India. In addition, we analyzed their gene expression in Peripheral blood Mononuclear cells (PBMC) from 15 PSCI cases and 12 controls. The mRNA data for BDNF was further validated by its plasma level through ELISA (n = 38). Among the studied variants, only rs4580704/CLOCK showed an overall association with PSCI (P = 0.001) and lower Bengali Mini-Mental State Examination (BMSE) score. Its 'C' allele showed a correlation with attention deficiency. The language and memory impairments showed association with rs6265/BDNF, while the 'CC' genotype of rs2292912/CRY2 negatively influenced language and executive function. A significant decrease in gene expression for CLOCK and BDNF in PBMC (influenced by specific genotypes) of PSCI patients was observed than controls. Unlike Pro-BDNF, plasma-level mBDNF was also lower in them. Our results suggest the genetic variants in CLOCK, CRY2, and BDNF as risk factors for PSCI among eastern Indians. At the same time, a lowering expression of CLOCK and BDNF genes in PSCI patients than controls describes their transcriptional dysregulation as underlying mechanism for post-stroke cognitive decline.

Association between post-stroke cognitive impairment and gut microbiota: A PRISMA-compliant systematic review and meta-analysis.

Accumulating evidence has indicated a possible connection between post-stroke cognitive impairment (PSCI) and gut microbiota imbalance. To further investigate this association, the present work was designed to systematically assess the dissimilarity of gut microbiota between PSCI and healthy individuals or stroke patients. A meta-analysis and systematic review was conducted by searching various databases including PubMed, Web of Science, Embase, VIP, CNKI, and Wangfang for relevant studies. The pooled outcomes were used to estimate the combined dissimilarity of gut microbiota composition between PSCI and healthy individuals or patients with stroke. Nine eligible studies were included in this meta-analysis. The results showed that there were no significant changes in observed richness indexes (Chao1 and ACE) and Shannon index. Notably, a significant decrease in Simpson index was observed in PSCI patients in comparison to the healthy individuals (-0.31, 95% CI: -0.62 to -0.01, P = 0.04). Moreover, the microbiota composition at the phylum level (increased abundance of Proteobacteria), family level (increased abundance of Bacteroidaceae, Lachnospiraceae, and Veillonellaceae; decreased abundance of Enterobacteriaceae), and genus level (increased abundance of Bacteroides, Clostridium XIVa, and Parabacteroides; decreased abundance of Prevotella and Ruminococcus) was found to be significantly different between PSCI and controls. This meta-analysis suggests a significant shift of observed species and microbiota composition in PSCI compared to healthy individuals or patients with stroke.

Effect of Rehabilitation Robot Training on Cognitive Function in Stroke Patients : A Systematic Review and Meta-analysis

Objective: Post-stroke cognitive impairment is one of the major dysfunction after stroke, which can lead to a variety of negative health outcomes. This study aims to evaluate the effects of rehabilitation robotic therapy in post-stroke cognitive impairment patients.
 Methods: As of December 2022, PubMed, Embase, Web of Science, Cochrane Library, and China National Knowledge Infrastructure were searched through electronic databases. Eligibility criteria RCTs evaluate RCTs of rehabilitation robots on treatment events in patients with cognitive impairment after stroke, compared to control groups.
 Results: Eight studies were included (n = 431). When combined with routine cognitive training efficacy, rehabilitation robot intervention observably reduced MOCA scores, MBI scores and FMA score. Furthermore, the FIM scores and MMSE scores were also better than the control groups. Rehabilitation robots training can improve the cognitive function of stroke patients and is an effective means of stroke rehabilitation.

Comparing conventional treatment, single-target rTMS, or dual-target rTMS for the treatment of post-stroke cognitive impairment — clinical effects and neuroscientific insights: study protocol for a randomized controlled trial

BackgroundAlthough increasing evidence suggests that repetitive transcranial magnetic stimulation may help improve cognitive impairment after stroke, its clinical efficacy is still limited. This limitation may be due to the fact that the left dorsolateral prefrontal cortex (DLPFC) is only one of several brain areas involved in post-stroke cognitive impairment (PSCI). The aim of the present study is to reveal whether dual-target stimulation is superior to single-target stimulation and usual care in the treatment of PSCI.MethodsA single-center, single-blind, randomized controlled trial will be conducted, and fifty-seven PSCI patients will be recruited and randomly assigned to one of three groups based on the stimulating site. The primary outcome is cognitive function, measured using the Montreal Cognitive Assessment Beijing Version (MoCA-BJ) and Mini-Mental Status Examination (MMSE). The secondary outcomes are the modified Barthel Index (MBI), Trail-Making Test (TMT), and digital span test (DST). Furthermore, changes in brain activity are assessed using transcranial Doppler sonography (TCD) examination and serum levels of brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) closely related to nerve and vascular repair after brain injury. All outcomes will be measured at baseline and 4 weeks after treatment.DiscussionIf dual-target rTMS in significant improvements in cognitive function, this method could be considered as a first-line clinical treatment for PSCI. This proposed study has the potential to identify a new, evidence-based intervention that can enhance cognition and independent living in patients with cognitive impairment after stroke.Trial registrationChinese Clinical Trial Registry ChiCTR2200066184. It was registered on 26 November 2022.

Plasma exosome proteomics reveals the pathogenesis mechanism of post-stroke cognitive impairment.

Exploration and utilization of exosome biomarkers and their related functions provide the possibility for the diagnosis and treatment of post-stroke cognitive impairment (PSCI). To identify the new diagnostic and prognostic biomarkers of plasma exosome were uzed label-free quantitative proteomics and biological information analysis in PSCI patients. Behavioral assessments were performed, including the Mini-Mental Status Examination (MMSE), the Montreal Cognitive Assessment (MoCA), the Barthel index, the Morse Fall Seale (MFS) between control group (n = 10) and PSCI group (n = 10). The blood samples were collected to analyse the biomarker and differentially expressed proteins of plasma exosome using label-free quantitative proteomics and biological information. The exosomes marker proteins were determined by Western blot. The exosome morphology was observed by transmission electron microscopy. The scores of MMSE and MoCA were significantly decreased in the PSCI group. The PT% and high-density lipoprotein decreased and the INR ratio increased in PSCI group. The mean size of exosome was approximately 71.6 nm and the concentration was approximately 6.8E+7 particles/mL. Exosome proteomics identified 259 differentially expressed proteins. The mechanisms of cognitive impairment are related to regulate the degradation of ubiquitinated proteins, calcium dependent protein binding, cell adhesive protein binding, formation of fibrin clot, lipid metabolism and ATP-dependent degradation of ubiquitinated proteins in plasma exosome of PSCI patients. Plasma levels of YWHAZ and BAIAP2 were significantly increased while that of IGHD, ABCB6 and HSPD1 were significantly decreased in PSCI patients. These proteins might be target-related proteins and provide global insights into pathogenesis mechanisms of PSCI at plasma exosome proteins level.

Clinical Features, Brain-Structure Changes, and Cognitive Impairment in Basal Ganglia Infarcts: A Pilot Study.

Stroke has been considered to raise the risk of dementia in several studies, but the relationship between brain structural changes and poststroke cognitive impairment (PSCI) is unclear. In this study, 23 PSCI patients with basal ganglia infarcts after 2 weeks and 29 age-matched controls underwent magnetic resonance imaging measuring cortical thickness and volume changes, as well as neuropsychological tests. CI was derived from a performance score <1.5 standard deviations for normally distributed scores. We compared Z scores in different cognitive domains and cortical thickness and volumes in two groups. Multiple linear regressions were used to investigate the relationship between cortical thickness and volumes and neuropsychological tests. A majority of PSCI patients were in their 50s (55.19±8.52 years). PSCI patients exhibited significantly decreased Z scores in multiple domains, such as memory, language, visuomotor speed, and attention/executive function. The volumes of the middle posterior corpus callosum, middle anterior corpus callosum, and hippocampus in PSCI patients were markedly lower than controls. The thickness of the right inferior temporal cortex and insula were significantly smaller than controls. It found that the reduced right hippocampus was related to executive dysfunction. Hippocampus dysfunction may be involved in language impairment (p<0.05) in PSCI patients with basal ganglia infarcts. These findings demonstrated that brain structure changed after ischemic stroke, and different gray-matter structural changes could lead to specific cognitive decline in PSCI patients with basal ganglia infarcts. Atrophy of the right hippocampus potentially serves as an imaging marker of early executive function of PSCI.

Altered static and dynamic functional network connectivity in post-stroke cognitive impairment

Post-stroke cognitive impairment (PSCI) is a common symptom following brain stroke, yet the mechanisms remain unknown. This study aimed to investigate alterations of static and dynamic functional network connectivity (sFNC and dFNC) in PSCI patients. We prospectively recruited 17 PSCI patients and 24 Healthy controls (HC). Restingstate fMRI (rs-fMRI) and Mini-Mental State Examination (MMSE) were performed. Independent component analysis combined with sliding-window and K-means clustering approach were applied to examine the FNC among 11 resting-state networks: auditory network (AUDN), left executive control network (lECN), language network (LN), precuneus network (PCUN), right executive control network (rECN), salience network (SN), visuospatial network (VN), dorsal default mode network (dDMN), higher visual network (hVIS), primary visual network (pVIS), and ventral mode network (vDMN). The FNC and dynamic indices (fraction time, mean dwell time, transition number) were calculated. Static and dynamic measures were compared between two groups and the correlation between clinical and imaging indicators was analyzed. For sFNC, PSCI group showed decreased interactions in dDMN-vDMN, vDMN-SN, dDMN-hVIS, AUDN-rECN, and AUDN-VN. For dFNC, we derived 3 states of FNC that occurred repeatedly. Significant group differences were found, including decreased interactions in the AUDN-VN, AUDN-pVIS in state 2 and dDMN-VN in state 3. The mean dwell time in PSCI group was longer in state 1, and negatively correlated with MMSE score. These results demonstrated that PSCI patients are characterized with altered sFNC and dFNC, which could help us explore the neural mechanisms of the PSCI from a new perspective.

Relationships of Low Serum Levels of Interleukin-10 With Poststroke Anxiety and Cognitive Impairment in Patients With Clinical Acute Stroke.

The relationships among interleukin (IL)-10 levels, anxiety, and cognitive status after stroke remain controversial. We aimed to determine the associations of serum IL-10 levels with poststroke anxiety (PSA) and poststroke cognitive impairment (PSCI). We recruited 350 patients with stroke, of whom only 151 completed a 1-month follow-up assessment. The Mini Mental State Examination (MMSE) and Hamilton Anxiety Scale (HAMA) were used to assess the cognitive status and anxiety, respectively. Serum IL-10 levels were measured within 24 hours of admission. IL-10 levels were significantly lower in the PSA group than in the non-PSA group, and they were negatively associated with HAMA scores (r=-0.371, p<0.001). After adjusting for all potential confounders, IL-10 levels remained an independent predictor of PSA (odds ratio=0.471, 95% confidence interval=0.237-0.936, p=0.032). IL-10 levels were strongly correlated with behavior during interviews, psychic anxiety, and somatic anxiety. Patients without PSCI had higher IL-10 levels were higher in non-PSCI patients than in PSCI patients, and they were positively associated with MMSE scores in the bivariate correlation analysis (r=0.169, p=0.038), and also with memory capacity, naming ability, and copying capacity. However, IL-10 did not predict PSCI in the univariable or multivariable logistic regression. Low IL-10 levels were associated with increased risks of PSA and PSCI at a 1-month follow-up after stroke. Serum IL-10 levels may therefore be helpful in predicting PSA.

Structural network efficiency mediates the association between glymphatic function and cognition in mild VCI: a DTI-ALPS study.

Background and objective: Vascular cognitive impairment (VCI) can be caused by multiple types of cerebrovascular pathology and is considered a network disconnection disorder. The heterogeneity hinders research progress in VCI. Glymphatic failure has been considered as a key common pathway to dementia recently. The emergence of a new method, Diffusion Tensor Image Analysis Along the Perivascular Space (DTI-ALPS), makes it possible to investigate the changes of the glymphatic function in humans non-invasively. We aimed to investigate alterations of glymphatic function in VCI and its potential impact on network connectivity. Methods: We recruited 79 patients with mild VCI, including 40 with cerebral small vessel disease cognitive impairment (SVCI) and 39 with post-stroke cognitive impairment (PSCI); and, 77 normal cognitive (NC) subjects were recruited. All subjects received neuropsychological assessments and multimodal magnetic resonance imaging scans. ALPS-index was calculated and structural networks were constructed by deterministic tractography, and then, the topological metrics of these structural connectivity were evaluated. Results: The ALPS-index of VCI patients was significantly lower than that of NC subjects (P < 0.001). Multiple linear regression analysis showed that ALPS-index affects cognitive function independently (β = 0.411, P < 0.001). The results of correlation analysis showed that the ALPS-index was correlated with overall vascular risk factor burden (r = -0.263, P = 0.001) and multiple cerebrovascular pathologies (P < 0.05). In addition, global efficiency (Eg) of network was correlated with ALPS-index in both SVCI (r = 0.348, P = 0.028) and PSCI (r = 0.732, P < 0.001) patients. Finally, the results of mediation analysis showed that Eg partially mediated in the impact of glymphatic dysfunction on cognitive impairment (indirect effect = 7.46, 95% CI 4.08-11.48). Conclusion: In both major subtypes of VCI, the ALPS-index was decreased, indicating impaired glymphatic function in VCI. Glymphatic dysfunction may affect cognitive function in VCI by disrupting network connectivity, and, may be a potential common pathological mechanism of VCI. ALPS-index is expected to become an emerging imaging marker for VCI.

Cerebral activity manipulation of low-frequency repetitive transcranial magnetic stimulation in post-stroke patients with cognitive impairment.

The aim of this study was to evaluate the therapeutic effect of low-frequency repetitive transcranial magnetic stimulation (rTMS) on post-stroke cognitive impairment (PSCI). Thirty-six PSCI patients were randomly divided into treatment and control groups of equal size. Both groups were pre-treated with conventional cognitive rehabilitation training. Subsequently, the treatment group was exposed to 1 Hz low-frequency repetitive transcranial magnetic stimulations for 8 weeks, with 5 days per week. Meanwhile, the control group was treated with placebo stimulations. Patients were evaluated via the LOTCA scale assessments and changes in P300 latencies and amplitudes before and after 8 weeks of treatment. Before treatment, there were no significant differences between the two groups in LOTCA scores, P300 latencies, and amplitudes (P > 0.05). After treatment, LOTCA scores for both groups improved (P < 0.05), and those of the treatment group were higher than those of the control (P < 0.05). For both groups, P300 latencies were not only shortened but also had greater amplitudes (P < 0.05), and those for the treatment group were significantly shorter and larger than those of the control (P < 0.05). As a therapy, rTMS improved cognitive function in PSCI patients, possibly via regulation of neural electrical activity of the cerebral cortex.

Effects of dual-task training in patients with post-stroke cognitive impairment: A randomized controlled trial.

Evidence for the efficacy of cognitive-motor dual-task (CMDT) training in patients with post-stroke cognitive impairment (PSCI) and no dementia is still lacking. More importantly, although some studies on the cognitive effect of CMDT training show an improvement in cognitive performance, the results are still controversial, and the intervention mechanism of CMDT training on cognitive function improvement is not clear. The main purpose of this study was to analyze the effects of CMDT training on cognitive function, neuron electrophysiology, and frontal lobe hemodynamics in patients with PSCI. Here we tested the effects of CMDT training on cognitive function in PSCI patients. Forty subjects who met the criteria of PSCI were randomly assigned to control and experimental groups. CMDT training or cognitive task (CT) training was administered to each patient in the experimental and control groups, respectively. All subjects performed Mini-mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) scale before and after the intervention, and the event-related potentials (ERP) and functional near-infrared spectroscopy (fNIRS) were used to evaluate the changes in neuron electrophysiology and hemodynamics. Forty patients were randomized across Beijing Rehabilitation Hospital Capital Medical University in Beijing. At the end of the intervention, 33 subjects completed the experimental process. The CMDT group showed significant improvement in the MMSE (P = 0.01) and MoCA (P = 0.024) relative to the CT group. The results of ERP and fNIRS showed that CMDT training could shorten the latency of P300 (P = 0.001) and the peak time of oxygenated hemoglobin (P = 0.004). The results showed that CMDT training shortened the response time of central neurons and significantly increased the rate of oxygen supply to the frontal lobe. CMDT training in patients with PSCI improved global cognitive function, which was supported by the improved neural efficiency of associated brain areas. http://www.chictr.org.cn, identifier ChiCTR2000034862.

The relationship between altered degree centrality and cognitive function in mild subcortical stroke: A resting-state fMRI study

Background and PurposePatients with post stroke cognitive impairment (PSCI) frequently show changes in brain functional connectivity (FC). However, the underlying neurobiological mechanism of PSCI remains unclear. This study first applied degree centrality (DC) analysis to investigate the intrinsic dysconnectivity pattern of the brain in PSCI patients, as well as to explore the relationship between these changes and cognitive function. MethodsResting-state functional magnetic resonance imaging (rs-fMRI) scanning was performed on all participants, including those with PSCI (n = 20), stroke with no cognitive impairment (NPSCI, n = 15), and healthy controls (HC, n = 29). DC values were used to identify differences in FC among the three groups. The relationship between abnormal DC values and cognitive function was examined. ResultsPSCI and NPSCI had significantly higher DC values in the right parahippocampal gyrus (PhG) in comparison with HC (p＜0.05). In addition, DC values of the right PhG showed a negative correlation with MoCA scores (r = − 0.405, p = 0.001), the Auditory Verbal Learning Test (AVLT; r = − 0.278, p = 0.026), Rey-Osterrieth Complex Figure Test-Delayed Recall (RCFT-DR; r = − 0.250, p = 0.046), Symbol Digit Modality Test (SDMT; r = − 0.385, p = 0.002), Boston Naming Test (BNT; r = − 0.402, p = 0.001) and Animal Fluency Test (AFT; r = − 0.395, p = 0.001). However, DC was significantly positively correlated with the Trail Making Test (TMT-A; r = 0.347, p = 0.005) and TMT-B (r = 0.294, p = 0.019). ConclusionsDC values were increased in the right PhG following a mild subcortical stroke. DC values in the PhG were negatively correlated with cognitive function, which may indicate brain nodes reorganization.

The resting-state topological organization damage of language-related brain regions in post-stroke cognitive impairment.

The topology of brain networks is the foundation of cognition. We hypothesized that stroke damaged topological organization resulting in cognitive impairment. The aim was to explore the damage pattern of the resting-state topology in post-stroke cognitive impairment (PSCI) patients.Thirty-seven patients with PSCI and thirty-seven gender- and age-matched healthy controls (HC) were recruited. The structural and functional data were collected from all subjects. The degree centrality (DC), betweenness centrality (BC), and global properties of brain networks were analyzed between groups. Spearman correlation analysis was performed between topological properties that changed significantly and clinical cognitive function scale scores.Compared with HC, the PSCI patients had significantly reduced DC in language-related brain regions and significantly higher DC in the right frontal lobe, hippocampus, and paracentral lobule. The decreased BC was located in the left caudate, thalamus, temporal, and frontal lobes. The increased BC was detected in the left cuneus and right precuneus. In addition, PSCI exhibited increased characteristic path length and decreased small-worldness.PSCI patients had impaired functional topology of the language-related brain regions, mainly in the left hemisphere. The enhanced processing and relaying information of some right high-order cognitive brain regions may be a compensatory mechanism. However, the whole brain's function integration was reduced, and there was an imbalance between efficiency and consumption.

Suboptimal states and frontoparietal network-centered incomplete compensation revealed by dynamic functional network connectivity in patients with post-stroke cognitive impairment.

BackgroundNeural reorganization occurs after a stroke, and dynamic functional network connectivity (dFNC) pattern is associated with cognition. We hypothesized that dFNC alterations resulted from neural reorganization in post-stroke cognitive impairment (PSCI) patients, and specific dFNC patterns characterized different pathological types of PSCI.MethodsResting-state fMRI data were collected from 16 PSCI patients with hemorrhagic stroke (hPSCI group), 21 PSCI patients with ischemic stroke (iPSCI group), and 21 healthy controls (HC). We performed the dFNC analysis for the dynamic connectivity states, together with their topological and temporal features.ResultsWe identified 10 resting-state networks (RSNs), and the dFNCs could be clustered into four reoccurring states (modular, regional, sparse, and strong). Compared with HC, the hPSCI and iPSCI patients showed lower standard deviation (SD) and coefficient of variation (CV) in the regional and modular states, respectively (p < 0.05). Reduced connectivities within the primary network (visual, auditory, and sensorimotor networks) and between the primary and high-order cognitive control domains were observed (p < 0.01).ConclusionThe transition trend to suboptimal states may play a compensatory role in patients with PSCI through redundancy networks. The reduced exploratory capacity (SD and CV) in different suboptimal states characterized cognitive impairment and pathological types of PSCI. The functional disconnection between the primary and high-order cognitive control network and the frontoparietal network centered (FPN-centered) incomplete compensation may be the pathological mechanism of PSCI. These results emphasize the flexibility of neural reorganization during self-repair.

Short-term Montreal Cognitive Assessment predicts functional outcome after endovascular therapy.

BackgroundThe previous studies have shown that cognition in patients 4–8 weeks after stroke can predict early functional outcomes after stroke. The analyses of data from the REVASCAT trial proved that stent thrombectomy improves post-morbid wiring test outcomes in patients with AIS compared with drug therapy. However, few studies focus on the relationship between cognitive impairment and functional outcomes in patients undergoing endovascular treatment.MethodsA total of 647 participants registered from stroke centers. Stroke severity was evaluated by National Institutes of Health stroke scale (NIHSS). The functional status was estimated by modified Rankin scale (mRS). The cognitive impairment was assessed by trained neurologists at 14 (±4) and 90 (±7) days after stroke onset using the Montreal Cognitive Assessment (MoCA). A MoCA score of less than 26 was considered post-stroke cognitive impairment (PSCI).ResultsA total of 120 Patients who underwent endovascular therapy were included. The PSCI group had higher levels of age, men, educational status, atrial fibrillation, smoking, alcoholism, Alberta Stroke Program Early CT (ASPECT) score of the anterior circulation, and OTP time than the non-PSCI group (p < 0.05). In contrast, the 14-day MoCA score, 14-day NIHSS score, 3-month MoCA score, 3-month NIHSS score, 3-month mRS score, and 3-month EQ5D score were lower in those PSCI patients. The risk predictors of PSCI were age, sex, educational level, atrial fibrillation, smoking, alcoholism, ASPECT Score (anterior circulation), 14-day MoCA score, and 14-day NIHSS score. There were strong relationships between 3-month NIHSS and MoCA (r = –0.483, p < 0.001). Receiver operating characteristic (ROC) curve indicated that 14-day MoCA score, memory, abstraction, visuospatial/executive functions, attention, and language, played a significant role to predict PSCI [area under the curve (AUC) > 0.7]. It had predictive value for the 14-day visuospatial/executive functions to predict 3-month functional outcomes.ConclusionEarly application of the MoCA in different cognitive regions could predict the PSCI and future functional outcomes, which is necessary to screen high-risk patients with poor prognosis and conduct an early intervention.

Efficacy of Intermittent Theta-Burst Stimulation and Transcranial Direct Current Stimulation in Treatment of Post-Stroke Cognitive Impairment.

The efficacy of intermittent theta-burst stimulation (iTBS) and transcranial direct current stimulation (tDCS) combined with cognitive training in the treatment of post-stroke cognitive impairment (PSCI) requires further investigation. We randomly assigned 60 patients with PSCI to receive iTBS (n = 21), tDCS (n = 19), or cognitive training alone (n = 20). Cognitive function was evaluated by the Loewenstein Occupational Therapy Cognitive Assessment (LOTCA), and the performance of activities of daily living (ADL) was assessed with the modified Barthel Index (MBI). Of these patients, 14 participated in the functional near-infrared spectroscopy (fNIRS) measurement. After six weeks of treatment, cognitive function improved in all three groups of PSCI patients. Compared with patients receiving only cognitive training, the cognitive function of patients in the iTBS combined with cognitive training (p = 0.003) and tDCS combined with cognitive training groups (p = 0.006) showed greater improvement. The cognitive improvement from tDCS was related to the activation of the frontopolar cortex (FPC), while the improvement of cognition by iTBS was based on the activation of the stimulation site (the dorsolateral prefrontal cortex) and some distant regions. Both iTBS and tDCS in addition to cognitive training appear to improve cognitive function and quality of life of patients with PSCI, compared to cognitive training alone. tDCS improved cognitive function by improving the patient's valuation, motivation, and decision-making substructures, while iTBS improved patients' assessment and decision-making abilities, improving cognitive control and, ultimately, overall cognitive function.

Lower serum BDNF as a predictor of post-stroke cognitive impairment in acute ischemic stroke patients

Background: Reduced level of serum BDNF in acute stroke patients is associated with poor outcomes. We aimed to identify the role of serum BDNF level as a predictor for post-stroke cognitive impairment (PSCI). Methods: This was a prospective study. We recruited acute ischemic stroke patients in Dr. Sardjito General Hospital Yogyakarta, Indonesia followed them up for 90 days (3 months). Serum BDNF was collected at day 5 and day 30 of stroke onset and measured by ELISA. Montreal Cognitive Assessment (MoCA) was used to measure the cognitive function at 90 days of follow up. ROC curve was conducted to measure the cut-off point of the BDNF level. Factors independently associated with PSCI were analyzed by using stepwise regression. Results: Among 89 patients recruited, 60 patients (67.41%) developed PSCI. The mean age of PSCI and non-PSCI patients was 62.7 ± 9.5 and 57.5 ± 8.7, respectively (p = 0.01). Patients with dyslipidemia were less likely to develop PSCI (OR 0.19, 95%CI 0.06–0.56, p &lt; 0.05). In addition, patients with day 5-serum BDNF level &lt; 23.29 ng/mL were five times more likely to develop PSCI compared with their counterparts (OR 5.02, 95%CI 1.67–15.04, p &lt; 0.05). Conclusions: Among acute ischemic stroke patients, those with serum BDNF &lt;23.29 ng/mL had a higher risk of developing PSCI, while those with dyslipidemia had a lower risk of PSCI. This study suggests that BDNF could be a predictor of PSCI, allowing for earlier detection and better preventive strategies.