Cognitive testing following transient ischaemic attack: A systematic review of clinical assessment tools

Cognitive deficits are prevalent after transient ischaemic attack (TIA) and result in loss of function, poorer quality of life and increased risks of dependency and mortality. This systematic review aimed to synthesise the available evidence on cognitive assessment in TIA patients to determine the prevalence of cognitive deficits, and the optimal tests for cognitive assessment. Medline, Embase, PsychINFO and CINAHL databases were searched for relevant articles. Articles were screened by title and abstract. Full-text analysis and quality assessment was performed using the National Institute of Health Tool. Data were extracted on study characteristics, prevalence of TIA deficits, and key study findings. Due to significant heterogeneity, meta-analysis was not possible. Twenty-five full-text articles met the review inclusion criteria. There was significant heterogeneity in terms of cognitive tests used, definitions of cognitive impairment and TIA, time points post-event, and analysis methods. The majority of studies used the Mini-Mental State Examination (MMSE) or Montreal Cognitive Assessment (MoCA) (n = 23). Prevalence of cognitive impairment ranged from 2% to 100%, depending on the time-point and cognitive domain studied. The MoCA was more sensitive than the MMSE for identifying cognitive deficits. Deficits were common in executive function, attention, and language. No studies assessed diagnostic test accuracy against a reference standard diagnosis of cognitive impairment. Recommendations on cognitive testing after TIA are hampered by significant heterogeneity between studies, as well as a lack of diagnostic test accuracy studies. Future research should focus on harmonising tools, definitions, and time-points, and validating tools specifically for the TIA population

Effects of brain training on brain blood flow (The Cognition and Flow Study-CogFlowS): protocol for a feasibility randomised controlled trial of cognitive training in dementia.

INTRODUCTION: Cognitive training is an emerging non-pharmacological treatment to improve cognitive and physical function in mild cognitive impairment (MCI) and early Alzheimer's disease (AD). Abnormal brain blood flow is a key process in the development of cognitive decline. However, no studies have explored the effects of cognitive training on brain blood flow in dementia. The primary aim of this study is to assess the feasibility for a large-scale, randomised controlled trial of cognitive training in healthy older adults (HC), MCI and early AD. METHODS AND ANALYSIS: This study will recruit 60 participants, in three subgroups of 20 (MCI, HC, AD), from primary, secondary and community services. Participants will be randomised to a 12-week computerised cognitive training programme (five × 30 min sessions per week), or waiting-list control. Participants will undergo baseline and follow-up assessments of: mood, cognition, quality of life and activities of daily living. Cerebral blood flow will be measured at rest and during task activation (pretraining and post-training) by bilateral transcranial Doppler ultrasonography, alongside heart rate (3-lead ECG), end-tidal CO2 (capnography) and beat-to-beat blood pressure (Finometer). Participants will be offered to join a focus group or semistructured interview to explore barriers and facilitators to cognitive training in patients with dementia. Qualitative data will be analysed using framework analysis, and data will be integrated using mixed methods matrices. ETHICS AND DISSEMINATION: Bradford Leeds Research Ethics committee awarded a favourable opinion (18/YH/0396). Results of the study will be published in peer-reviewed journals, and presented at national and international conferences on ageing and dementia. TRIALS REGISTRATION NUMBER: NCT03656107; Pre-results

The role of the autonomic nervous system in cerebral blood flow regulation in dementia: A review

In this review we will examine the role of the autonomic nervous system in the control of cerebral blood flow (CBF) in dementia. Worldwide, 55 million people currently live with dementia, and this figure will increase as the global population ages. Understanding the changes in vascular physiology in dementia could pave the way for novel therapeutic approaches. Reductions in CBF have been demonstrated in multiple dementia sub-types, in addition to increased cerebrovascular resistance and reduced vasoreactivity. Cerebral autoregulation (CA) is a key mechanism for the maintenance of cerebral perfusion, but remains largely intact in cognitive disorders, despite reductions in global and regional CBF. However, the tight coupling between neuronal activity and CBF (neurovascular coupling - NVC) is lost in dementia, which may be a key driver of cognitive dysfunction. Despite numerous studies investigating disturbances in the control of CBF in dementia, less is known about the specific mechanisms responsible for the observed changes. Disturbances could be related to one of a number of pathways and mechanisms including disruption of the autonomic component. In this review we will explore clinical and animal studies, which specifically investigated the autonomic component of CBF control in dementia, drawing on the clinical implications and potential for novel biomarker and therapeutic targets

Frailty factors and outcomes in vascular surgery patients: a systematic review and meta-analysis

Objective To describe and critique tools used to assess frailty in vascular surgery patients, and investigate its associations with patient factors and outcomes. Background Increasing evidence shows negative impacts of frailty on outcomes in surgical patients, but little investigation of its associations with patient factors has been undertaken. Methods Systematic review and meta-analysis of studies reporting frailty in vascular surgery patients (PROSPERO registration: CRD42018116253) searching Medline, Embase, CINAHL, PsycINFO and Scopus. Quality of studies was assessed using Newcastle Ottawa scores (NOS) and quality of evidence using GRADE criteria. Associations of frailty with patient factors were investigated by difference in means (MD) or expressed as risk ratios (RR), and associations with outcomes expressed as odds ratios (OR) or hazard ratios (HR). Data were pooled using random effects models. Results Fifty-three studies were included in the review and only 8 (15%) were both good quality (NOS ≥7) and used a well-validated frailty measure. Eighteen studies (62,976 patients) provided data for the meta-analysis. Frailty was associated with increased age (MD 4.05 years; 95% confidence interval [CI] 3.35, 4.75), female sex (RR 1.32; 95%CI 1.14, 1.54), and lower body-mass index (MD -1.81; 95%CI -2.94, -0.68). Frailty was associated with 30-day mortality (adjusted [A]OR 2.77; 95%CI 2.01-3.81), post-operative complications (AOR 2.16; 95%CI 1.55, 3.02) and long-term mortality (HR 1.85; 95%CI 1.31, 2.62). Sarcopenia was not associated with any outcomes. Conclusion Frailty, but not sarcopenia, is associated with worse outcomes in vascular surgery patients. Well-validated frailty assessment tools should be preferred clinically, and in future research.</div

Leg Ischaemia Management collaboration (LIMb): study protocol for a prospective cohort study at a single UK centre

Introduction Severe limb ischaemia (SLI) is the end-stage of peripheral arterial occlusive disease where the viability of the limb is threatened. Around 25% of patients with SLI will ultimately require a major lower limb amputation which has a substantial adverse impact on quality of life. A newly established rapid-access vascular limb salvage clinic and modern revascularisation techniques may reduce amputation rate. The aim of this study is to investigate the 12-month amputation rate in a contemporary cohort of patients and compare this to a historical cohort. Secondary aims are to investigate the use of frailty and cognitive assessments, and cardiac MRI in risk-stratifying patients with SLI undergoing intervention and establish a biobank for future biomarker analyses. Methods & analysis This single-centre prospective cohort study will recruit patients aged 18-110 years presenting with SLI. Those undergoing intervention will be eligible to undergo additional venepuncture (for biomarker analysis) and/or cardiac MRI. Those aged ≥65 years and undergoing intervention will also be eligible to undergo additional frailty and cognitive assessments. Follow-up will be at 12 and 24 months and subsequently via data-linkage with NHS digital to 10 years post-recruitment. Those undergoing cardiac MRI and/or frailty assessments will receive additional follow-up during the first 12 months to investigate for peri-operative myocardial infarction and frailty related outcomes, respectively. A sample size of 420 patients will be required to detect a 10% reduction in amputation rate in comparison to a similar sized historical cohort, with 90% power and 5% type-I error rate. Statistical analysis of this comparison will be by adjusted and unadjusted logistic regression analyses. Ethics & dissemination Ethical approval for this study has been granted by the UK National Research Ethics Service (19/LO/0132). Results will be disseminated to participants, via scientific meetings, peerreviewed medical journals and social media. Study registration ClinicalTrials.gov [NCT04027244