Post-stroke Cognitive Impairment Patients Research Articles

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.

Relationship between Post-Stroke Cognitive Impairment and Severe Dysphagia: A Retrospective Cohort Study.

Objective: To investigate the relationship between post-stroke cognitive impairment (PSCI) and severe post-stroke dysphagia (PSD) and explore the risk factors related to PSCI combined with severe PSD. Methods: Data from patients were collated from the rehabilitation-specific disease database. The Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Videofluoroscopy Swallowing Study (VFSS), Penetration-aspiration Scale (PAS), and Functional Oral Intake Scale (FOIS) were used to evaluate cognitive and swallowing functions. Differences between groups were determined by the Pearson chi-square test (χ2) or Fisher exact test. PAS and FOIS data were analyzed with the use of the Wilcoxon rank-sum or Kruskal–Wallis test in the prespecified subgroup analysis. Risk factors were investigated by multivariate logistic regression. Results: A total of 1555 patients were identified with PSCI. The results indicated that patients with PSCI had a higher incidence rate of severe PSD as compared to patients without PSCI (p < 0.001). Patients with severe PSCI were more likely to clinically manifest oral phase dysfunction (p = 0.024), while mild PSCI patients mainly manifested pharyngeal phase dysfunction (p < 0.001). There was a significant difference in FOIS score changes between subgroups during the hospitalization period (severe PSCI vs. moderate PSCI and severe PSCI vs. mild PSCI) (all p < 0.001). In addition, multivariate logistic regression revealed pneumonia (p < 0.001), tracheotomy (p < 0.001), and dysarthria (p = 0.006) were related to PSCI, combined with severe PSD. Conclusion: PSCI may be related to severe PSD. Patients with severe PSCI were more likely to manifest oral phase dysfunction, while mild PSCI manifested pharyngeal phase dysfunction. Pneumonia, tracheotomy, and dysarthria were risk factors related to PSCI combined with severe PSD.

Clinical observation of taking acupuncture at the acupoints based on "four seas theory" for post-stroke cognitive impairment 基于“四海理论”组穴针刺治疗脑卒中后认知障碍的临床观察

ObjectiveTo observe the clinical effect on post-stroke cognitive impairment (PSCI) treated by acupuncture at the acupoints composed in accordance with the "four seas theory". MethodsA total of 70 patients with PSCI were randomly divided into a treatment group (n = 35) and a control group (n = 35). In the control group, conventional basic treatment and rehabilitation training were adopted, while in the treatment group, on the base of the treatment as the control group, acupuncture was applied at the acupoints composed in accordance with "four seas theory", lasting 8 weeks. The scores of mini-mental state examination (MMSE) and the instantaneous memory, the scores of Montreal cognitive assessment (MoCA) and the delayed memory, the score of kidney essence insufficiency in syndrome differentiation scale of vascular dementia (SDSVD), event-related potentials (ERP) P300 and clinical therapeutic effect were compared in the patients between two groups before and after treatment separately. ResultsAfter treatment, MMSE score and the score of instantaneous memory were higher than the results before treatment in either group respectively (all P < 0.05), in which, MMSE score in the treatment group was higher than that in the control group (P < 0.05). After treatment, MoCA score and the score of delay recall were higher than the results before treatment in either group (all P < 0.05), in which, MoCA score in the treatment group was higher than that of the control group (P < 0.05). After treatment, the score of SDSVD was lower than that before treatment in either group (both P < 0.05), in which SDSVD score in the treatment group were lower than the control group (P < 0.05). There were no statistical changes in P300 latency and wave amplitude in the patients of the control group after treatment (both P > 0.05). However, in the treatment group, P300 latency was reduced and the wave amplitude was increased after treatment (both P < 0.05). The total effective rate was 88.57% in the treatment group, higher than 71.43% in the control group (P < 0.05). ConclusionAcupuncture at the acupoints composed on the base of the "four seas theory” effectively improves the cognitive function and traditional Chinese medicine syndrome scores in PSCI patients. This therapy is of great value in clinic in the future.

Effect of Early Cognitive Training Combined with Aerobic Exercise on Quality of Life and Cognitive Function Recovery of Patients with Poststroke Cognitive Impairment.

Objective To explore the effect of early cognitive training combined with aerobic exercise on quality of life (QOL) and cognitive function recovery of patients with poststroke cognitive impairment (PSCI). Methods Ninety PSCI patients treated in our hospital from April 2019 to April 2020 were selected as the subjects and were divided into the experimental group (EG) and control group (CG) according to the admission order, with 45 cases each. Patients in CG received conventional health education combined with rehabilitation training, and those in EG accepted early cognitive training combined with aerobic exercise so as to evaluate the clinical effect of different intervention modes on PSCI patients. Results Compared with CG after intervention, EG obtained an obviously higher Stroke Specific Quality of Life scale (SS-QOL) score, Montreal Cognitive Assessment (MoCA) score, Barthel Index (MBI) (BI) score and Functional Independence Measure (FIM) score (P < 0.001), and obviously shorter time for completing TMT-A and TMT-B (P < 0.001). Conclusion Performing early cognitive training combined with aerobic exercise for PSCI patients can effectively improve their QOL and promote the recovery of cognitive function. Compared with conventional health education combined with rehabilitation training, this mode presents a higher application value. Further study will be conducive to establishing a better solution for patients.

Evaluation of the Effects of Folic Acid Combined with Atorvastatin on the Poststroke Cognitive Impairment by Low-Rank Matrix Denoising Algorithm-Based MRI Imaging.

This research aimed to study the optimization effects of the low-rank matrix denoising (LRMD) algorithm based on the Gaussian mixture model (GMM) on MRI images of stroke patients, aiming to evaluate the effects of atorvastatin combined with folic acid on poststroke cognitive impairment (PSCI) in patients with ischemic stroke. First, the GMM-based low-rank matrix denoising (LRMD) algorithm was constructed and applied to process MRI images of 64 patients with ischemic stroke. Then, the MRI images before and after processing were compared for the denoising degree and quality. An image with 5% noise was not as clear as an MRI image with 1% noise, and the effects of atorvastatin combined with folic acid on PSCI in patients with ischemic stroke were discussed. It was found that the denoising degree of MRI images processed by the GMM-based LRMD algorithm was significantly improved, the image quality was significantly enhanced (P < 0.05), and the diagnosis accuracy and efficiency of stroke patients were heightened. Atorvastatin combined with folic acid reduce the homocysteine (HCY) and total cholesterol (TC) levels, as well as Montreal Cognitive Scale (MOCA) scores of PSCI patients (P < 0.05). In conclusion, the MRI images processed by the LRMD algorithm have good quality. Folic acid combined with atorvastatin can effectively reduce HCY and TC levels, thereby alleviating PSCI of stroke patients.

Evaluation of White Matter Microstructural Alterations in Patients with Post-Stroke Cognitive Impairment at the Sub-Acute Stage.

PurposeTo investigate white matter alterations in post-stroke cognitive impairment (PSCI) patients at the subacute stage employing diffusion kurtosis and tensor imaging.MethodsThirty PSCI patients at the subacute phase and 30 healthy controls (HC) underwent diffusion kurtosis imaging (DKI) scans and neuropsychological assessments. Based on the tract-based spatial statistics and atlas-based ROI analysis, fractional anisotropy (FA), mean diffusivity (MD), mean kurtosis (MK), kurtosis fractional anisotropy (KFA), axial kurtosis (AK), and radial kurtosis (RK) were compared in specific white matter fiber bundles between the groups (with family-wise error correction). Adjusting for age and gender, a partial correlation was conducted between neurocognitive assessments and DKI metrics in the PSCI group.ResultsIn comparison with the HC, PSCI patients significantly showed decreased MK, RK, and FA and increased MD values in the genu of corpus callosum, anterior limb internal capsule, and left superior corona radiata. In addition, DKI detected more white matter region changes in MK (31/48), KFA (40/48), and RK (25/48) than DTI with FA (28/48) and MD (21/48), which primarily consisted of the right cingulum, right superior longitudinal fasciculus, and left posterior limb of internal capsule. In the left anterior limb of internal capsule, MK and RK values were significantly negatively correlated with TMT-B (r = −0.435 and −0.414, P < 0.05), and KFA values (r = −0.385, P < 0.05) of corpus callosum negatively associated with TMT-B.ConclusionCombing DTI, DKI, and neuropsychological tests, we found extensive damaged white matter microstructure and poor execution performance in subacute PSCI patients. DKI could detect more subtle white matter changes than DTI metrics. Our findings provide added information for exploring the mechanisms of PSCI and conducting cognitive rehabilitation in the subacute stage.

Decreased Functional Connectivities of Low-Degree Level Rich Club Organization and Caudate in Post-stroke Cognitive Impairment Based on Resting-State fMRI and Radiomics Features

BackgroundStroke is an important cause of cognitive impairment. Rich club organization, a highly interconnected network brain core region, is closely related to cognition. We hypothesized that the disturbance of rich club organization exists in patients with post-stroke cognitive impairment (PSCI).MethodsWe collected data on resting-state functional magnetic resonance imaging (rs-fMRI) with 21 healthy controls (HC), 16 hemorrhagic stroke (hPSCI), and 21 infarct stroke (iPSCI). 3D shape features and first-order statistics of stroke lesions were extracted using 3D slicer software. Additionally, we assessed cognitive function using the Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE).ResultsNormalized rich club coefficients were higher in hPSCI and iPSCI than HC at low-degree k-levels (k = 1–8 in iPSCI, k = 2–8 in hPSCI). Feeder and local connections were significantly decreased in PSCI patients versus HC, mainly distributed in salience network (SN), default-mode network (DMN), cerebellum network (CN), and orbitofrontal cortex (ORB), especially involving the right and left caudate with changed nodal efficiency. The feeder and local connections of significantly between-group difference were positively related to MMSE and MoCA scores, primarily distributed in the sensorimotor network (SMN) and visual network (VN) in hPSCI, SN, and DMN in iPSCI. Additionally, decreased local connections and low-degree ϕnorm(k) were correlated to 3D shape features and first-order statistics of stroke lesions.ConclusionThis study reveals the disrupted low-degree level rich club organization and relatively preserved functional core network in PSCI patients. Decreased feeder and local connections in cognition-related networks (DMN, SN, CN, and ORB), particularly involving the caudate nucleus, may offer insight into pathological mechanism of PSCI patients. The shape and signal features of stroke lesions may provide an essential clue for the damage of functional connectivity and the whole brain networks.

Abstract WP208: Post-stroke Cognitive Impairment And The Risk Of Recurrent Stroke And Death: A Systematic Review

Post-stroke cognitive impairment (PSCI) occurs in 20%-40% of stroke patients and was reported to be a risk factor of recurrent stroke and death. However, to date, no systematic review and meta-analysis exists to precisely estimate the associated risk. The goal of the current study was to conduct a systematic review of published literature on the association between PSCI and risk of recurrent stroke and death. We searched Ovid MEDLINE and Scopus for studies published from 1992 to 2019, combining the following keywords: post-stroke cognitive impairment, risk of stroke recurrence, mortality, post-stroke dementia. Of the 929 references, we identified 23 studies (n=28,305 patients) that met eligibility criteria. The time of PSCI diagnosis ranged from 7 days to 6 months, and 3-month after stroke was the most common time point of neuropsychological testing. The majority (65%, 15/23) of these studies evaluated PSCI mortality endpoint (n = 23,554), while 35% (8/23) looked at combined endpoint of recurrent stroke and death (n= 4,751). In mortality studies, 86% (13/15) showed significantly higher risk of death in PSCI patients compared to those without it (OR/HR/RR range from 1.42 to 7.42). In the two largest studies (n=8,822 and n=6,504), the adjusted HR were 1.42 (1.34-1.50) and RR 2.0 (1.3-3.2) respectively. Only 14% (2/15) of the studies showed negative results. However, one negative study [HR: 1.00 (0.79-1.86)] included a large cohort (n=3,948). In recurrence studies, 75% (6/8) reported higher risk with OR/HR/RR ranging from 1.48 to 4.86. Subgroup analyses in the two largest recurrence clinical trial studies (n=1,528 and n=1,240) reported HR 1.48 (1.04-2.09) and OR 2.32 (1.10-4.89). No association between PSCI and recurrent stroke was found in 25% (2/8) of recurrence studies including those with n=458 [HR 1.74 (0.89-3.39)] and n=202 patients [RR 1.25 (0.47-3.33)].This systematic review revealed about a 0.5 to 7 times increased risk of recurrent stroke and death in patients with PSCI suggesting that PSCI might be a marker predicting recurrent events in secondary stroke prevention. A meta-analysis is warranted to increase the precision and validity of risk estimates of PSCI and study the bases for differences across studies.

Diagnostic performance of miR-21, miR-124, miR-132, and miR-200b serums in post-stroke cognitive impairment patients.

The diagnosis of post-stroke cognitive impairment (PSCI) mainly depends on neuro-psychological evaluation. It still lacks a sensitive and objective diagnostic biomarker. MicroRNAs (miRNAs, miRs) are novel and potential disease biomarkers. Our aim was to detect which specific miRNA is a good diagnostic biomarker for PSCI. There were 77 first-ever stroke patients enrolled. Blood samples were collected at 14 days after stroke. Level of serum miR-21, miR-124, miR-132, and miR-200b were determined by quantitative polymerase chain reaction. Mini-mental state examination (MMSE) scale was used to measure the cognitive function of patients. Factional anisotropy (FA) score of diffusion tensor imaging was applied to detect the alteration of white matter. In addition, the relationship between miRNA level and cognitive status was further explored by correlation analysis. Finally, 45 PSCI and 32 post-stroke cognitive normality (PSCN) patients were enrolled. The expression of miR-21, miR-132, and miR-200b in PSCI patients was higher than in PSCN patients. In particular, the miR-21 level was substantially correlated with MMSE scores (r = 0.752, p < 0.001) and FA value (r = 0.636, p < 0.001). Additionally, the diagnostic performance of miR-21 alone or the combination of miR-21 and FA values performed well. The miR-21 alone or combination of miR-21 and FA values are valuable diagnostic biomarkers in discriminating PSCI from PSCN.

Computer aided self-regulation learning and cognitive training improve generalization ability of patients with poststroke cognitive impairment

Emerging studies suggest the application of self-regulation learning (SRL) to improve generalization abilities in poststroke patients. SRL has been proposed to have an added effect on computer-aided cognitive training (CACT). This study aimed to examine the efficacy of an intervention combining computer-aided SRL (CA-SRL) training and CACT for generalization abilities and cognitive function in patients with poststroke cognitive impairment (PSCI). A total of 75 patients recruited from a rehabilitation centre were randomly assigned to a CA-SRL group, demonstration learning (DL) group and traditional learning (TL) group. Finally, 72 patients were included in the analysis. Over 3 weeks, the patients in these three groups underwent CA-SRL or DL training combined with cognitive training. After the intervention, all outcomes significantly improved (P < 0.05). The CA-SRL group showed better improvements in all trained tasks among the groups, especially in "wash the dishes" and “change the bed”. The results of the analysis for generalization abilities showed that CA-SRL group patients obtained the highest scores among the groups in untrained tasks. The mean changes in the Montreal Cognitive Assessment in both the CA-SRL and TL groups were significantly higher than those in the DL group (P < 0.001, P = 0.002) after adjusting for education level and Lawton Instrumental ADL Scale score. In general, the combination of CA-SRL and CACT is effective for PSCI patients and has a better effect on promoting skill generalization from cognitive gains than traditional training.

The effects of blood pressure on post stroke cognitive impairment: BP and PSCI.

Cognitive function following acute ischemic stroke (AIS) is critical to prognosis and quality of life. Hypertension is a risk factor for stroke and is associated with post stroke cognitive impairment (PSCI). However, the optimal blood pressure parameters after AIS is unknown. This is a sub‐study of the Impairment of CognitiON and Sleep after acute ischemic stroke or transient ischemic attack in Chinese patients (ICONS) study conducted between August 2015 and March 2018. Cognition was assessed at two‐week (2w), three‐month (3 m), and twelve‐month (12 m) by Montreal Cognitive Assessment (MoCA). A total of 682 participants who met the inclusion criteria were enrolled. The primary outcome was cognitive changes after 3 and 12 months post stroke. Among 682 participants, the mean age was 59.35 ± 10.40 years and 72.29% were men. PSCI patients with high systolic blood pressure (SBP ≥140 mm Hg) at 3 m not only had worse cognition as evidenced by MoCA scores at 3 m but also predicted worse scores at 12 m. When participants were stratified into cognitively stable/improved (MoCA score ≥0, 2w vs. 12 m) and cognitively impaired (MoCA score ≤‐2, 2w vs. 12 m), those with high SBP were more likely to be cognitively impaired (OR 2.17, 95%CI 1.12–4.21, p < .05) and less likely to be cognitively stable/improved (OR 0.66, 95%CI 0.44–0.99, p < .05). SBP more than 140 mm Hg is associated with worse cognitive performance after ischemic stroke. Patients with SBP lower than 140 mm Hg have better cognitive outcome at 3‐month and 1 year after stroke.

Dysbiosis of Gut Microbiota in Patients with Post-Stroke Cognitive Impairment

To identify the differences in the composition of gut microbiota of patients with post-stroke cognitive impairment (PSCI) in comparison with the normal cognition healthy controls (HC), and to study the potential association between gut microbiota and cognition function. A total of 24 patients were recruited for the PSCI group, which was matched with 23 healthy subjects with no history of cardiovascular disease recruited over the same period for the control group. Fecal samples were collected for both groups, and Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) were used to evaluate cognitive functions. The abundance, diversity and group difference of gut bacterial communities were determined with 16S rRNA gene sequencing, and the correlations between differences in bacterial species of the gut microbiota and cognitive function scores were examined with redundancy analysis (RDA)/canonical correspondence analysis (CCA). There was no significant difference in the general data or the alpha diversity of gut microbiota between the two groups ( P>0.05). Inter-group comparison of microbial species composition revealed differences at the phylum and species levels, mainly represented as reduction in the relative abundance of Firmicutes and Bacteroidetes, and the relative enrichment of Proteobacteria. The relative abundance of Intestinibacter bartlettii, uncultured bacterium Tyzzerella_3, Lactobacillus gasseri, and Fusicatenibacter saccharivorans of phylum Firmicutes in the PSCI patients were significantly reduced in comparison to that of the HC (LDA score>2), and these bacteria were positively correlated with MMSE and MoCA scores. In addition, the Ruminococcus gnavus and Faecalimonas umbilicata of phylum Firmicutes and uncultured bacterium Prevotellaceae_NK3 B31 group of phylum Bacteroidetes were significantly enriched in comparison with those of the HC (LDA score>2), and these bacteria were negatively correlated with MMSE and MoCA scores. There were also correlations among these bacteria. In this study, we observed compositional differences between the gut microbiota of PSCI patients and those of HC, and revealed that the differences were correlated, to some degree, to the cognitive functions, which will provide new perspectives for the clinical diagnosis and treatment of PSCI.

Using Fractional Amplitude of Low-Frequency Fluctuations and Functional Connectivity in Patients With Post-stroke Cognitive Impairment for a Simulated Stimulation Program.

Stroke causes alterations in local spontaneous neuronal activity and related networks functional connectivity. We hypothesized that these changes occur in patients with post-stroke cognitive impairment (PSCI). Fractional amplitude of low-frequency fluctuations (fALFF) was calculated in 36 patients with cognitive impairment, including 16 patients with hemorrhagic stroke (hPSCI group), 20 patients with ischemic stroke (iPSCI group). Twenty healthy volunteers closely matched to the patient groups with respect to age and gender were selected as the healthy control group (HC group). Regions with significant alteration were regarded as regions of interest (ROIs) using the one-way analysis of variance, and then the seed-based functional connectivity (FC) with other regions in the brain was analyzed. Pearson correlation analyses were performed to investigate the correlation between functional indexes and cognitive performance in patients with PSCI. Our results showed that fALFF values of bilateral posterior cingulate cortex (PCC)/precuneus and bilateral anterior cingulate cortex in the hPSCI group were lower than those in the HC group. Compared with the HC group, fALFF values were lower in the superior frontal gyrus and basal ganglia in the iPSCI group. Correlation analysis showed that the fALFF value of left PCC was positively correlated with MMSE scores and MoCA scores in hPSCI. Besides, the reduction of seed-based FC values was reported, especially in regions of the default-mode network (DMN) and the salience network (SN). Abnormalities of spontaneous brain activity and functional connectivity are observed in PSCI patients. The decreased fALFF and FC values in DMN of patients with hemorrhagic and SN of patients with ischemic stroke may be the pathological mechanism of cognitive impairment. Besides, we showed how to use fALFF values and functional connectivity maps to specify a target map on the cortical surface for repetitive transcranial magnetic stimulation (rTMS).