The Post Ischaemic Stroke Cardiovascular Exercise Study: Protocol for a randomised controlled trial of fitness training for brain health

Relationship between the amount of physical activity and brain structure in patients with chronic stroke

OBJECTIVES

The association between the amount of physical activity and the brain structure in patients with stroke is unclear. Therefore, this study aimed to evaluate the structural characteristics of the brain in patients with chronic stroke engaging in varying levels of physical activity.

METHODS

This study included 10 healthy participants and 10 patients with stroke. Structural images were obtained, and the physical activity of patients with stroke was measured using a triaxial accelerometer. Additionally, the brain structure was assessed using voxel-based morphometry for gray and white matter volumes. The analysis software used were Statistical Parametric Mapping 12 and MATLAB version R2020a. The differences in brain structure between healthy participants and stroke patients were investigated. The brain regions associated with the amount of physical activity were analyzed.

RESULTS

There was a significant decrease in the gray matter volume of the contralesional cerebellum and ipsilesional thalamus in stroke patients when compared with healthy participants (p < 0.001, uncorrected). Patients with stroke showed a positive correlation between physical activity and the volume of the ipsilesional precentral gyrus and ipsilesional entorhinal area (p < 0.001, uncorrected).

CONCLUSIONS

The amount of physical activity in patients with chronic hemiplegic stroke is associated with brain gray matter mass.

ZOom Delivered Intervention Against Cognitive decline (ZODIAC) COVID-19 pandemic adaptations to the Post-Ischaemic Stroke Cardiovascular Exercise Study (PISCES): protocol for a randomised controlled trial of remotely delivered fitness training for brain health

BACKGROUND

Stroke increases subsequent dementia risk yet there are no specific post-stroke therapies to protect cognition. Cardiorespiratory exercise is recommended for secondary prevention of stroke and may be neuroprotective. The Post Ischaemic Stroke Cardiovascular Exercise Study (PISCES) aims to reduce post-stroke secondary neurodegeneration and cognitive decline. During the pandemic, we pivoted to a ZOom Delivered Intervention Against Cognitive decline (ZODIAC) protocol, reducing pandemic-amplified barriers to exercise.

METHODS

We present pandemic adaptions for a multicentre phase IIb assessor-blinded randomised controlled trial of ischaemic stroke survivors testing the efficacy and feasibility of an 8-week home-based exercise intervention delivered at 2 months post-stroke. We compare cardiorespiratory exercise (intervention arm) versus balance and stretching (active control arm). Participants are assessed with magnetic resonance imaging (MRI), fitness, blood, microbiome, and neuropsychological tests at three study visits: before and after the exercise intervention and at 12 months. Modifications to the original protocol include pre-exercise safety home visits, commercial delivery of exercise equipment to facilitate assessor blinding, and reconsideration of statistical plan to allow pooling of the studies. We have reduced in-person study visits from 27 to 3. Primary outcome remains between-group (intervention versus control) difference in brain volume change; secondary outcome is between-group difference in global cognitive ability to allow remote administration of a validated cognitive scale.

DISCUSSION

Remotely delivered exercise interventions reduce participant burden and may reduce barriers to recruitment. A decrease in the number of in-person study visits can be supported by greater information capture via self-reported questionnaires and phone surveys.

TRIAL REGISTRATION

Prospectively ACTRN12616000942459. Registered on July 2016.

Train Smart Study: protocol for a randomised trial investigating the role of exercise training dose on markers of brain health in sedentary middle-aged adults

INTRODUCTION

Regular aerobic exercise is associated with improved cognitive function, implicating it as a strategy to reduce dementia risk. This is reinforced by the association between greater cardiorespiratory fitness and larger brain volume, superior cognitive performance and lower dementia risk. However, the optimal aerobic exercise dose, namely the intensity and mode of delivery, to improve brain health and lower dementia risk has received less attention. We aim to determine the effect of different doses of aerobic exercise training on markers of brain health in sedentary middle-aged adults, hypothesising that high-intensity interval training (HIIT) will be more beneficial than moderate-intensity continuous training (MICT).

METHODS AND ANALYSIS

In this two-group parallel, open-label blinded endpoint randomised trial, 70 sedentary middle-aged (45-65 years) adults will be randomly allocated to one of two 12-week aerobic exercise training interventions matched for total exercise training volume: (1) MICT (n=35) or HIIT (n=35). Participants will perform ~50 min exercise training sessions, 3 days per week, for 12 weeks. The primary outcome will be measured as between-group difference in cardiorespiratory fitness (peak oxygen uptake) change from baseline to the end of training. Secondary outcomes include between-group differences in cognitive function and ultra-high field MRI (7T) measured markers of brain health (brain blood flow, cerebrovascular function, brain volume, white matter microstructural integrity and resting state functional brain activity) changes from baseline to the end of training.

ETHICS AND DISSEMINATION

The Victoria University Human Research Ethics Committee (VUHREC) has approved this study (HRE20178), and all protocol modifications will be communicated to the relevant parties (eg, VUHREC, trial registry). Findings from this study will be disseminated via peer-review publications, conference presentations, clinical communications and both mainstream and social media.

TRIAL REGISTRATION NUMBER

ANZCTR12621000144819.

Brain age predicts long-term recovery in post-stroke aphasia

The association between age and language recovery in stroke remains unclear. Here, we used neuroimaging data to estimate brain age, a measure of structural integrity, and examined the extent to which brain age at stroke onset is associated with (i) cross-sectional language performance, and (ii) longitudinal recovery of language function, beyond chronological age alone. A total of 49 participants (age: 65.2 ± 12.2 years, 25 female) underwent routine clinical neuroimaging (T1) and a bedside evaluation of language performance (Bedside Evaluation Screening Test-2) at onset of left hemisphere stroke. Brain age was estimated from enantiomorphically reconstructed brain scans using a machine learning algorithm trained on a large sample of healthy adults. A subsample of 30 participants returned for follow-up language assessments at least 2 years after stroke onset. To account for variability in age at stroke, we calculated proportional brain age difference, i.e. the proportional difference between brain age and chronological age. Multiple regression models were constructed to test the effects of proportional brain age difference on language outcomes. Lesion volume and chronological age were included as covariates in all models. Accelerated brain age compared with age was associated with worse overall aphasia severity (F(1, 48) = 5.65, P = 0.022), naming (F(1, 48) = 5.13, P = 0.028), and speech repetition (F(1, 48) = 8.49, P = 0.006) at stroke onset. Follow-up assessments were carried out ≥2 years after onset; decelerated brain age relative to age was significantly associated with reduced overall aphasia severity (F(1, 26) = 5.45, P = 0.028) and marginally failed to reach statistical significance for auditory comprehension (F(1, 26) = 2.87, P = 0.103). Proportional brain age difference was not found to be associated with changes in naming (F(1, 26) = 0.23, P = 0.880) and speech repetition (F(1, 26) = 0.00, P = 0.978). Chronological age was only associated with naming performance at stroke onset (F(1, 48) = 4.18, P = 0.047). These results indicate that brain age as estimated based on routine clinical brain scans may be a strong biomarker for language function and recovery after stroke.

Exercise for Stroke Rehabilitation: A Bibliometric Analysis of Global Research From 2001 to 2021

Objective

To make a bibliometric analysis of global trends in research into exercise interventions for stroke between 2001 and 2021.

Method

This study did the systematic literature from 2001 to 2021 in Web of Science Core Collection. CiteSpace software was used to analyze the relationship of publications with countries, journals, authors, references, and keywords.

Results

A total of 3,484 publications were obtained in the bibliometric analysis. The number of publications increased gradually over the period. The United States have the most number of publications. The journal stroke had the most citations per paper (106.95) and the highest impact factor (IF 2020, 7.194). The most high frequency keywords are “stroke,” “rehabilitation,” and “recovery,” the top of burst key words are “health,” “speed,” and “aerobic exercise”.

Conclusion

These findings provide the trends of exercise for stroke s and provided the potential research frontiers in the past 20 years. It will be a useful basis for further research into focus issues, cooperators, development trends.

Neurodegeneration Over 3 Years Following Ischaemic Stroke: Findings From the Cognition and Neocortical Volume After Stroke Study

Background: Stroke survivors are at high risk of dementia, associated with increasing age and vascular burden and with pre-existing cognitive impairment, older age. Brain atrophy patterns are recognised as signatures of neurodegenerative conditions, but the natural history of brain atrophy after stroke remains poorly described. We sought to determine whether stroke survivors who were cognitively normal at time of stroke had greater total brain (TBV) and hippocampal volume (HV) loss over 3 years than controls. We examined whether stroke survivors who were cognitively impaired (CI) at 3 months following their stroke had greater brain volume loss than cognitively normal (CN) stroke participants over the next 3 years.

Methods: Cognition And Neocortical Volume After Stroke (CANVAS) study is a multi-centre cohort study of first-ever or recurrent adult ischaemic stroke participants compared to age- and sex-matched community controls. Participants were followed with MRI and cognitive assessments over 3 years and were free of a history of cognitive impairment or decline at inclusion. Our primary outcome measure was TBV change between 3 months and 3 years; secondary outcomes were TBV and HV change comparing CI and CN participants. We investigated associations between group status and brain volume change using a baseline-volume adjusted linear regression model with robust standard error.

Results: Ninety-three stroke (26 women, 66.7 ± 12 years) and 39 control participants (15 women, 68.7 ± 7 years) were available at 3 years. TBV loss in stroke patients was greater than controls: stroke mean (M) = 20.3 cm³ ± SD 14.8 cm³; controls M = 14.2 cm³ ± SD 13.2 cm³; [adjusted mean difference 7.88 95%CI (2.84, 12.91) p-value = 0.002]. TBV decline was greater in those stroke participants who were cognitively impaired (M = 30.7 cm³; SD = 14.2 cm³) at 3 months (M = 19.6 cm³; SD = 13.8 cm³); [adjusted mean difference 10.42; 95%CI (3.04, 17.80), p-value = 0.006]. No statistically significant differences in HV change were observed.

Conclusions: Ischaemic stroke survivors exhibit greater neurodegeneration compared to stroke-free controls. Brain atrophy is greater in stroke participants who were cognitively impaired early after their stroke. Early cognitive impairment was associated greater subsequent atrophy, reflecting the combined impacts of stroke and vascular brain burden. Atrophy rates could serve as a useful biomarker for trials testing interventions to reduce post-stroke secondary neurodegeneration.

Clinical Trail Registration:http://www.clinicaltrials.gov, identifier: NCT02205424.