Traditional Chinese Medicine for Post-Stroke Cognitive Impairment: A Systematic Review and Meta-Analysis

The effect and optimal parameters of repetitive transcranial magnetic stimulation on lower extremity motor function in stroke patient: a systematic review and meta-analysis

PURPOSE

This study aimed to evaluate the efficacy of repetitive transcranial magnetic stimulation (rTMS) in treating lower limb motor dysfunction after stroke and explore the optimal stimulation parameters.

METHODS

PubMed, Embase, Cochrane Library, and other relevant databases were systematically queried for randomised controlled trials (RCTs) investigating the efficacy of rTMS in addressing lower limb motor dysfunction post-stroke. The search encompassed records from inception to July 2022. The assessed outcomes encompassed parameters such as the Fugl-Meyer motor function score for lower limbs, balance function, and Barthel index (BI). Three independent researchers were responsible for research selection, data extraction, and quality assessment. Study screening, data extraction, and bias evaluation were performed independently by two reviewers. Data synthesis was undertaken using Review Manager 5.3, while Stata version 14.0 software was employed for generating the funnel plot.

RESULTS

A total of 13 studies and 428 patients were included. The meta-analysis indicated that rTMS had a positive effect on the BI (MD = 5.87, 95% CI [0.99, 10.76], p = 0.02, I2 = 86%, N of studies = 8, N of participants = 248). Subgroup analysis was performed on the stimulation frequency, treatment duration, and different stroke stages (stimulation frequency was low-frequency (LF)-rTMS (MD = 4.45, 95% CI [1.05, 7.85], p = 0.01, I2 = 0%, N of studies = 4, N of participants = 120); treatment time ≤ 15 d: (MD = 4.41, 95% CI [2.63, 6.18], p < 0.00001, I2 = 0%, N of studies = 4, N of participants = 124); post-stroke time ≤6 months: (MD = 4.37, 95% CI [2.42, 6.32], p < 0.0001, I2 = 0%, N of studies = 5, N of participants = 172).

CONCLUSION

LF-rTMS had a significant improvement effect on BI score, while high-frequency (HF)-rTMS and iTBS had no significant effect. And stroke time ≤6 months in patients with treatment duration ≤15 d had the best treatment effect.

Implications of neuromuscular electrical stimulation on gait ability, balance and kinematic parameters after stroke: a systematic review and meta-analysis

INTRODUCTIN

Improper gait patterns, impaired balance and foot drop consistently plague stroke survivors, preventing them from walking independently and safely. Neuromuscular electrical stimulation (NMES) technology can help patients reactivate their muscles and regain motor coordination. This study aims to systematically review and summarize the evidence for the potential benefits of NMES on the improvement of gait patterns after stroke.

EVIDENCE ACQUISITION

PubMed, Cochrane Library, Embase, Science Direct and Web of Science were systematically searched until April 2024, to identify randomized controlled trials with the following criteria: stroke survivors as participants; NMES as intervention; conventional rehabilitation as a comparator; and gait assessment, through scales or quantitative parameters, as outcome measures.

EVIDENCE SYNTHESIS

29 publications involving 1711 patients met the inclusion criteria. Meta-analysis showed no significant differences in Ten-meter walk test, Fugl-Meyer assessment lower extremity, Modified Ashworth Assessment and asymmetry between the NMES group and the control group. Besides, NMES was associated with changes in outcome indicators such as quantitative gait analysis speed [SMD = 0.53, 95% CI (0.20, 0.85), P = 0.001], cadence [SMD = 0.76, 95% CI (0.32, 1.20), P = 0.0008], affected side step length [SMD = 0.73, 95% CI (0.16, 1.31), P = 0.01], angle of ankle dorsiflexion [WMD = 1.57, 95% CI (0.80, 2.33), P < 0.0001], Six-Minute Walk Test [WMD = 14.83, 95% CI (13.55, 16.11), P<0.00001]. According to the PEDro scale, 21 (72.4%) studies were of high quality and 8 were of moderate quality (27.6%).

CONCLUSIONS

Taken together, the review synthesis indicated that NMES might play a potential role in stroke-induced walking dysfunction. And NMES may be superior for survivors in the chronic phase than the acute and subacute phases, and the efficacy of short sessions received by patients was greater than that of those who participated in a longer session. Additionally, further comparisons of the effects of NMES with different types or stimulation frequencies may provide unexpected benefits.

Brain activation patterns in patients with post-stroke cognitive impairment during working memory task: a functional near-infrared spectroscopy study

Objective

To explore the activation patterns in the frontal cortex of patients with post-stroke cognitive impairment during the execution of working memory tasks.

Methods

15 patients with post-stroke cognitive impairment, 17 patients without cognitive impairment, and 15 healthy controls of similar age and sex were included. All participants under-went immediate recall task testing and near-infrared spectroscopy imaging to measure frontal cortex activation during the task.

Results

The healthy control group performed the best in the immediate recall task, followed by the post-stroke non-cognitive impairment group. The post-stroke cognitive impairment group had the poorest performance. The near-infrared spectroscopy results revealed that during the immediate recall task, the healthy control group primarily activated the left frontal lobe region. In contrast, post-stroke patients exhibited reduced activation in the left frontal lobe and increased activation in the right frontal cortex, particularly in the right frontopolar and orbitofrontal regions, with the post-stroke cognitive impairment group displaying the most pronounced changes.

Conclusion

Patients with post-stroke cognitive impairment exhibit reduced activation in the left prefrontal cortex during the working memory tasks. They rely on compensatory activation in the right prefrontal cortex, particularly in the frontopolar and orbitofrontal cortex, to successfully complete the task.

Electroacupuncture improves the learning and memory abilities of rats with PSCI by attenuating the TLR4/NF-κB/NLRP3 signaling pathway on the hippocampal microglia

This study aims to investigate how electroacupuncture regulates the learning and memory abilities of poststroke cognitive impairment (PSCI) rats through the TLR4/NF-κB/NLRP3 signaling pathway on the hippocampal microglia. Thirty male rats were randomly divided into three groups: sham surgery group, PSCI model group, and electroacupuncture group, with 10 rats in each group. Middle cerebral artery occlusion was used to establish the PSCI model. The Zea Longa method was used to score the rats' neurological function. Electroacupuncture was utilized for 21 days to improve PSCI. The learning and memory abilities of rats were tested using the Morris water maze. Hematoxylin-eosin staining and immunofluorescence were used to find the hippocampus' pathological changes. The concentration of interleukin-1β, interleukin-6, tumor necrosis factor-α, and interleukin-18 were detected by ELISA. The mRNA expression levels of associated inflammatory corpuscles were measured by quantitative real-time PCR. The protein expression levels of TLR4, MyD88, NF-κB, and NLRP3 were measured using western blotting. Electroacupuncture improved not only the learning and memory abilities of PSCI rats but also hippocampal morphology. Electroacupuncture inhibited the activation of microglia and the TLR4/NF-κB/NLRP3 signaling pathway. Electroacupuncture also reduced proinflammatory factors and restrained the mRNA levels of NLRP3-associated inflammatory cytokines. Its mechanism was related to inhibiting the expression of the TLR4/NF-κB/NLRP3 signaling pathway, attenuating the release of inflammatory factors, and regulating the activation of hippocampal microglia in the brain.

The Janus face of HIF-1α in ischemic stroke and the possible associated pathways

Stroke is the most devastating disease, causing paralysis and eventually death. Many clinical and experimental trials have been done in search of a new safe and efficient medicine; nevertheless, scientists have yet to discover successful remedies that are also free of adverse effects. This is owing to the variability in intensity, localization, medication routes, and each patient's immune system reaction. HIF-1α represents the modern tool employed to treat stroke diseases due to its functions: downstream genes such as glucose metabolism, angiogenesis, erythropoiesis, and cell survival. Its role can be achieved via two downstream EPO and VEGF strongly related to apoptosis and antioxidant processes. Recently, scientists paid more attention to drugs dealing with the HIF-1 pathway. This review focuses on medicines used for ischemia treatment and their potential HIF-1α pathways. Furthermore, we discussed the interaction between HIF-1α and other biological pathways such as oxidative stress; however, a spotlight has been focused on certain potential signalling contributed to the HIF-1α pathway. HIF-1α is an essential regulator of oxygen balance within cells which affects and controls the expression of thousands of genes related to sustaining homeostasis as oxygen levels fluctuate. HIF-1α's role in ischemic stroke strongly depends on the duration and severity of brain damage after onset. HIF-1α remains difficult to investigate, particularly in ischemic stroke, due to alterations in the acute and chronic phases of the disease, as well as discrepancies between the penumbra and ischemic core. This review emphasizes these contrasts and analyzes the future of this intriguing and demanding field.

Therapeutic effectiveness of Donepezil hydrochloride in combination with butylphthalide for post-stroke cognitive impairment

OBJECTIVE

To study the therapeutic effectiveness of donepezil hydrochloride (DPZ) in combination with butylphthalide (BP) for the treatment of post-stroke cognitive impairment (PSCI).

METHODS

In this retrospective study, the clinical data of 125 PSCI patients treated at the First Affiliated Hospital of Harbin Medical University from December 2019 to December 2023 were collected and analyzed. The patients were grouped into a joint group (n=75, receiving DPZ + BP) and a control group (n=50, receiving DPZ alone) according to their treatment regimen. Inter-group comparisons were then carried out from the perspectives of therapeutic effectiveness, safety (constipation, abdominal distension and pain, and gastrointestinal reactions), cognitive function (Montreal Cognitive Assessment Scale [MoCA], Chinese Stroke Scale [CSS]), Activities of Daily Living Scale (ADL), and serum biochemical indexes (neuron-specific enolase [NSE], high-sensitivity C-reactive protein [hs-CRP], nitric oxide [NO], and malondialdehyde [MDA]). In addition, a univariate analysis was carried out to identify factors affecting therapeutic effectiveness in PSCI patients.

RESULTS

The joint group showed significantly better therapeutic effectiveness compared to the control group (P<0.05). There was a significant correlation between the type of stroke, treatment method, and therapeutic effectiveness in PSCI patients (P<0.05). There was no significant difference in the total incidence of adverse reactions (P>0.05). After the treatment, compared to the control group, the joint group demonstrated significant improvements in MoCA and ADL scores (all P<0.05) and reductions in CSS scores and levels of NSE, hs-CRP, NO, and MDA (all P<0.05).

CONCLUSIONS

DPZ in combination with BP is highly effective for the treatment of PSCI. It positively affects cognitive function and ADL, alleviates neurological deficits, and reduces abnormal serum biochemical indices without increasing the risk of adverse reaction.

How robot-assisted gait training affects gait ability, balance and kinematic parameters after stroke: a systematic review and meta-analysis

INTRODUCTION

Gait ability is often cited by stroke survivors. Robot-assisted gait training (RAGT) can help stroke patients with lower limb motor impairment regain motor coordination.

EVIDENCE ACQUISITION

PubMed, Cochrane Library, Embase were systematically searched until September 2023, to identify randomized controlled trials presenting: stroke survivors as participants; RAGT as intervention; conventional rehabilitation as a comparator; gait assessment, through scales or quantitative parameters, as outcome measures.

EVIDENCE SYNTHESIS

Twenty-seven publications involving 1167 patients met the inclusion criteria. Meta-analysis showed no significant differences in speed, cadence, spatial symmetry, and changes in joint mobility angles between the RAGT group and the control group. In addition, RAGT was associated with changes in affected side step length (SMD=0.02, 95% CI: 0.01, 0.03; P<0.0001), temporal symmetry (SMD=-0.38, 95% CI: -0.6, -0.16; P=0.0006], Six-Minute Walk Test (SMD=25.14, 95% CI: 10.19, 40.09; P=0.0010] and Functional Ambulation Categories (SMD=0.32, 95% CI: 0.01, 0.63; P=0.04). According to the PEDro scale, 19 (70.4%) studies were of high quality and eight were of moderate quality (29.6%).

CONCLUSIONS

Taken together, the review synthesis showed that RAGT might have a potential role in the recovery of walking dysfunction after stroke. However, its superiority over conventional rehabilitation requires further research. Additionally, it may provide unexpected benefits that the effects of RAGT with different types or treatment protocols were further compared.

Efficacy of intermittent theta burst stimulation (iTBS) on post-stroke cognitive impairment (PSCI): a systematic review and meta-analysis

BACKGROUND

Stroke is a significant global cause of mortality and morbidity, and post-stroke cognitive impairment (PSCI) affects up to half of stroke patients. Despite the availability of pharmacological and non-pharmacological interventions, there is a lack of definitive effective treatments for PSCI. Non-invasive brain stimulation, particularly intermittent theta burst stimulation (iTBS), has emerged as a promising therapy for the treatment of PSCI.

OBJECTIVE

This systematic review and meta-analysis aimed to evaluate the efficacy and safety of iTBS in enhancing cognitive function among patients with PSCI.

METHODS

A comprehensive search was conducted across multiple databases, including PubMed, Web of Science, Scopus, Cochrane Library, and CNKI, to identify relevant randomized controlled trials published before April 2023. The primary outcome measured changes in global cognitive scales, while the secondary outcomes focused on improvements in attention, orientation, visual-spatial perception, and activities of daily living.

RESULTS

The meta-analysis encompassed six studies involving 325 patients. The results demonstrated that iTBS led to a significant improvement in global cognitive scales (SMD = 1.12, 95% CI = [0.59 to 1.65], P < 0.0001), attention (SMD = 0.48, 95% CI [0.13 to 0.82], P = 0.007), visual perception (SMD = 0.99, 95% CI [0.13 to 1.86], P = 0.02), and activities of daily living (SMD = 0.82, 95% CI [0.55 to 1.08], P < 0.00001). However, there was no significant effect on orientation (SMD = 0.36, 95% CI [- 0.04 to 0.76], P = 0.07). Subgroup analysis based on the number of sessions was conducted, revealing a significant improvement in global cognition among patients with PSCI across the three categories (10 sessions, 20 sessions, and 30 sessions) with no between-group difference (P = 0.28). None of the included studies reported any serious adverse effects.

CONCLUSION

In conclusion, iTBS appears to be a safe and effective non-invasive treatment that can enhance the cognitive abilities and daily living skills of patients with post-stroke cognitive impairment. However, our conclusion is constrained by the limited number of studies. Further high-quality, large-sample RCTs with extended follow-up periods are necessary to validate these findings. Integrating iTBS with brain imaging techniques, such as functional near-infrared spectroscopy and functional magnetic resonance, could aid in understanding the mechanism of iTBS action.

Efficacy of scalp stimulation for multidomain cognitive impairment in patients with post-stroke cognitive impairment and dementia: A network meta-analysis and meta-regression of moderators

BACKGROUND

Scalp stimulation has gained more traction for post-stroke cognitive impairment and dementia (PSCID); the interaction between stimulation targets and parameters influences the response to the stimulation. However, the most efficacious treatment for improving different domains of cognitive impairment remains unknown.

OBJECTIVE

We aimed to conduct a systematic review and network meta-analysis (NMA) to compare the efficacy of various scalp stimulation protocols used in PSCID treatment.

METHODS

Randomized controlled trials of scalp stimulation in patients with PSCID were searched in eight databases over the past 20 years. Standardized mean differences (SMDs) for global and subdomain cognitive scores were pooled in Bayesian NMA. Moderators were examined using meta-regression analysis.

RESULTS

A total of 90 trials, with 6199 patients, were included. Low-frequency repetitive transcranial magnetic stimulation (rTMS) over the unaffected dorsolateral prefrontal cortex (DLPFC) was highly suggested for alleviating global severity (SMD = 1.11, 95% CI (0.64, 1.57)). High-frequency rTMS over the left DLPFC was recommended for language use (1.85 (1.18, 2.52)), executive function (0.85 (0.36, 1.33)), orientation deficits (0.59 (0.07, 1.13)), and attention (0.85 (0.27, 1.43)). Anodal transcranial direct current stimulation over the affected DLPFC (2.03 (0.72, 3.34)) was recommended for treating memory impairment. Meta-regression analyses showed significant associations within attention, language and orientation.

CONCLUSION

Overall, different cognitive domains have different optimal scalp stimulation prescriptions, and activating the affected key brain regions and inhibiting the unaffected area is still the most effective treatment.

Total saponins from Trillium tschonoskii Maxim promote neurological recovery in model rats with post-stroke cognitive impairment

Total saponins from Trillium tschonoskii Maxim (TSTT), a bioactive component of local natural herbs in the Enshi area, China, have been demonstrated to have functions of restoring cognitive capacity and promoting axonal regeneration post-stroke, but the mechanism of this process remains unclear. The hippocampus is a critical tissue for controlling learning and memory capacity, and the sonic hedgehog (Shh) signaling pathway plays a major role in the patterning and synaptic plasticity of hippocampal neural circuits. Therefore, we aimed to investigate whether TSTT could restore learning and cognitive functions by modulating the Shh pathway in rats with post-stroke cognitive impairment (PSCI). The ischemia model was established by permanent middle cerebral artery occlusion (MCAO) in 100 Sprague-Dawley (SD) rats, and the model rats were administered using TSTT (100 mg/kg) or donepezil hydrochloride as the positive control (daily 0.45 mg/kg, DON) for 4 weeks after the operation. As assessed by the Morris water maze test, the cognitive function of PSCI rats was significantly improved upon TSTT treatment. Meanwhile, the cerebral infarct volume reduced with TSTT, as shown by HE and TTC staining, and the number of Nissl bodies and dendritic spine density were significantly increased, as shown by Nissl and Golgi staining. In addition, TSTT upregulated PSD-95, SYN, and GAP-43, and inhibited neuronal apoptosis, as evidenced by increased Bcl-2 levels along with decreased Bax and caspase-3 expression. TSTT could also significantly upregulate Shh, Ptch1, Smo, and Gli1 proteins, indicating the activation of the Shh signaling pathway. Therefore, TSTT can protect PSCI rats by inhibiting apoptosis and promoting neuronal synaptic remodeling. The Shh pathway is also involved.

Effects of gastrodin on the expression of brain aging-related genes in SAM/P-8 mice based on network pharmacology

Background

Gastrodin can reduce neuronal damage through multiple targets and pathways, and can be useful in preventing and treating degenerative lesions of the central nervous system, but the specific mechanism has not been elucidated.

Methods

The aging-related genes in the hippocampus and the frontal cortex were detected in adult and aged mice treated with gastrodin or not. In addition, we collected the target genes of gastrodin and aging from a network database, and a Venn diagram was created to obtain the intersection target genes of gastrodin and aging. Then, the String database was used to analyze the protein-protein interactions (PPIs) between aging-related genes and the target genes of gastrodin and aging. The "drug-disease-target-pathway" network was constructed using Cytoscape 3.7.2 software, and the main mechanism and pathway of key genes were analyzed by Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO). Finally, the reliability of these key genes was further verified by molecular docking technology.

Results

The results showed that 6 out of 10 genes related to brain aging were differentially expressed after gastrodin intervention. Moreover, there were 11 key genes between gastrodin and differentially expressed genes related to brain aging. GO and KEGG results suggested that material metabolism and carbohydrate digestion and absorption were associated with the pathological mechanism of gastrodin antiaging. Molecular docking results also confirmed the good binding activity of gastrodin to the key genes.

Conclusion

Gastrodin plays a potential role in antiaging by regulating substance metabolism and carbohydrate digestion and absorption.

Excitatory Repetitive Transcranial Magnetic Stimulation Over the Ipsilesional Hemisphere for Upper Limb Motor Function After Stroke: A Systematic Review and Meta-Analysis

Background

Repetitive transcranial magnetic stimulation (rTMS) is a promising therapy to promote recovery of the upper limb after stroke. According to the regulation of cortical excitability, rTMS can be divided into excitatory rTMS and inhibitory rTMS, and excitatory rTMS includes high-frequency rTMS (HF-rTMS) or intermittent theta-burst stimulation (iTBS). We aimed to evaluate the effects of excitatory rTMS over the ipsilesional hemisphere on upper limb motor recovery after stroke.

Methods

Databases of PubMed, Embase, ISI Web of Science, and the Cochrane Library were searched for randomized controlled trials published before 31 December 2021. RCTs on the effects of HF-rTMS or iTBS on upper limb function in patients diagnosed with stroke were included. Two researchers independently screened the literature, extracted the data, and assessed quality. The meta-analysis was performed by using Review Manager Version 5.4 software.

Results

Fifteen studies with 449 participants were included in this meta-analysis. This meta-analysis found that excitatory rTMS had significant efficacy on upper limb motor function (MD = 5.88, 95% CI, 3.32–8.43, P < 0.001), hand strength (SMD = 0.53, 95% CI, 0.04–1.01, P = 0.03), and hand dexterity (SMD = 0.76, 95% CI, 0.39–1.14, P < 0.001). Subgroup analyses based on different types of rTMS showed that both iTBS and HF-rTMS significantly promoted upper limb motor function (iTBS, P < 0.001; HF-rTMS, P < 0.001) and hand dexterity (iTBS, P = 0.01; HF-rTMS, P < 0.001) but not hand strength (iTBS, P = 0.07; HF-rTMS, P = 0.12). Further subgroup analysis based on the duration of illness demonstrated that applying excitatory rTMS during the first 3 months (<1 month, P = 0.01; 1–3 months, P = 0.001) after stroke brought significant improvement in upper limb motor function but not in the patients with a duration longer than 3 months (P = 0.06). We found that HF-rTMS significantly enhanced the motor evoked potential (MEP) amplitude of affected hemisphere (SMD = 0.82, 95% CI, 0.32–1.33, P = 0.001).

Conclusion

Our study demonstrated that excitatory rTMS over the ipsilesional hemisphere could significantly improve upper limb motor function, hand strength, and hand dexterity in patients diagnosed with stroke. Both iTBS and HF-rTMS which could significantly promote upper limb motor function and hand dexterity, and excitatory rTMS were beneficial to upper limb motor function recovery only when applied in the first 3 months after stroke. HF-rTMS could significantly enhance the MEP amplitude of the affected hemisphere. High-quality and large-scale randomized controlled trials in the future are required to confirm our conclusions.

Clinical Trial Registration

www.crd.york.ac.uk/prospero/, identifier: CRD42022312288.

Potential Benefits of Music Therapy on Stroke Rehabilitation

Stroke is associated with a high rate of disability and mortality, and survivors are usually accompanied with dysphagia, aphasia, motor dysfunction, cognitive impairment, depression, and other complications. In the past decades, many studies have been conducted to reveal the pathogenesis and pathological mechanisms of stroke. Furthermore, treatment methods have been developed that contribute to the elevated survival rate of stroke patients. Early rehabilitation poststroke is starting to be recognized as important and has been receiving increasing attention in order to further improve the quality of life of the patients. As an emerging method of poststroke rehabilitation, music therapy can help attenuate dysphagia and aphasia, improve cognition and motor function, alleviate negative moods, and accelerate neurological recovery in stroke patients. This review helps summarize the recent progress that has been made using music therapy in stroke rehabilitation and is aimed at providing clinical evidence for the treatment of stroke patients.