Editor's Choice - Effect of Carotid Endarterectomy on 20 Year Incidence of Recorded Dementia: A Randomised Trial

Unstable Plaque is a Treatable Cause of Cognitive Decline

While many risk factors are modifiable, there remains a compelling need for novel approaches to prevent cognitive impairment. We propose that unstable carotid plaque causes microemboli that, in turn, cause microinfarcts and other adverse pathophysiological cerebral processes, which individually do not manifest clinically but cumulatively manifest as cognitive decline and ultimately cognitive impairment. Animal models support multiple cerebral microemboli having adverse effects on cognition. By addressing the source for microembolization by endarterectomy or stenting, patients with high-grade atherosclerotic stenosis may have better cognitive outcomes. If our hypothesis is verified, then treatment of carotid plaque at elevated risk of generating cerebral microemboli would be effective in preserving cognition, regardless of whether the stenosis is high-grade or causing cerebral hemispheric hypoperfusion.

Assessing Risk Factors for Cognitive Decline Using Electronic Health Record Data: A Scoping Review

Background

The data and information contained within electronic health records (EHR) provide a rich, diverse, longitudinal view of real-world patient histories, offering valuable opportunities to study antecedent risk factors for cognitive decline. However, the extent to which such records' data have been utilized to elucidate the risk factors of cognitive decline remains unclear.

Methods

A scoping review was conducted following the PRISMA guideline, examining articles published between January 2010 and April 2023, from PubMed, Web of Science, and CINAHL. Inclusion criteria focused on studies using EHR to investigate risk factors for cognitive decline. Each article was screened by at least two reviewers. Data elements were manually extracted based on a predefined schema. The studied risk factors were classified into categories, and a research gap was identified.

Results

From 1,593 articles identified, 80 were selected. The majority (87.5%) were retrospective cohort studies, with 66.3% using datasets of over 10,000 patients, predominantly from the US or UK. Analysis showed that 48.8% of studies addressed medical conditions, 31.3% focused on medical interventions, and 17.5% on lifestyle, socioeconomic status, and environmental factors. Most studies on medical conditions were linked to an increased risk of cognitive decline, whereas medical interventions addressing these conditions often reduced the risk.

Conclusions

EHR data significantly enhanced our understanding of medical conditions, interventions, lifestyle, socioeconomic status, and environmental factors related to the risk of cognitive decline.

William M. Feinberg Lecture: Asymptomatic Carotid Stenosis: Current and Future Considerations

Asymptomatic high-grade carotid stenosis is an important therapeutic target for stroke prevention. For decades, the ACAS (Asymptomatic Carotid Atherosclerosis Study) and ACST (Asymptomatic Carotid Surgery Trial) trials provided most of the evidence supporting endarterectomy for patients with asymptomatic high-grade stenosis who were otherwise good candidates for surgery. Since then, transfemoral/transradial carotid stenting and transcarotid artery revascularization have emerged as alternatives to endarterectomy for revascularization. Advances in treatments against atherosclerosis have driven down the rates of stroke in patients managed without revascularization. SPACE-2 (Stent-Protected Angioplasty Versus Carotid Endarterectomy-2), a trial that included endarterectomy, stenting, and medical arms, failed to detect significant differences in stroke rates among treatment groups, but the study was stopped well short of its recruitment goal. CREST-2 (Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial) will be able to clarify whether revascularization by stenting or endarterectomy remains efficacious under conditions of intensive medical management. Transcarotid artery revascularization has a favorable periprocedural risk profile, but randomized trials comparing it to intensive medical management are lacking. Features like intraplaque hemorrhage on MRI and echolucency on B-mode ultrasonography can identify patients at higher risk of stroke with asymptomatic stenosis. High-grade stenosis with poor collaterals can cause hemispheric hypoperfusion, and unstable plaque can cause microemboli, both of which may be treatable risk factors for cognitive impairment. Evidence that there are patients with carotid stenosis who benefit cognitively from revascularization is presently lacking. New risk factors are emerging, like exposure to microplastics and nanoplastics. Strategies to limit exposure will be important without specific medical therapies.

Post-stroke Everything

PURPOSE OF REVIEW

This review aims at providing updates on selected post-stroke complications. We examined recent advances in diagnosing and treating the following post-stroke complications: cognitive impairment, epilepsy, depression, fatigue, tremors, dysphagia, and pain.

RECENT FINDINGS

Advances in understanding the mechanisms of post-stroke complications, in general, are needed despite advances made in understanding, treating, and preventing these complications. There are growing progresses in integrating new tools to diagnose post-stroke cognitive impairment. The potential role of acute stroke reperfusion treatment in post-stroke epilepsy and its impact on other stroke complications is getting more transparent. Post-stroke depression remains underestimated and new tools to diagnose depression after stroke are being developed. New promising pharmacological approaches to treating post-stroke pain are emerging. Tremors related to stroke are poorly understood and under-evaluated, while treatment towards post-stroke dysphagia has benefited from new non-pharmacological to pharmacological approaches.

CONCLUSIONS

An integrative approach to stroke complications and collaborations between providers across specialties are more likely to improve stroke outcomes.

50 Shades of ‘Groundhog Day’

Introduction

The 2017 European Society for Vascular Surgery (ESVS) guidelines on carotid and vertebral artery disease concluded that the evidence did not support a role for carotid endarterectomy (CEA) or carotid artery stenting (CAS) in patients with asymptomatic carotid stenosis (ACS) in preventing cognitive impairment or dementia. What new data have emerged since 2017, and have they influenced the 2023 ESVS guidelines?

Report

In a systematic review, 33/35 studies (94%) reported a “significant association” between ACS and cognitive impairment; 20 studies had 1–3 tests with significant cognitive impairment; 10 reported 4–6 tests with cognitive impairment; and three studies reported ≥7 tests with significant cognitive impairment. Baseline data from 1 000 patients with ACS in the second Carotid Revascularisation Endarterectomy versus Stenting Trial (CREST-2) reported that the overall Z score for cognition in patients with ACS was significantly lower than expected, especially for word list recall and word list learning. Another systematic review reported that (in the long term) 69% of patients with ACS undergoing CEA/CAS had no change in cognitive function. However, in another 25%, cognitive scores/domains were mostly unchanged, but 1–2 individual tests were significantly improved. In addition, 1 601 UK and Swedish patients with ACS were randomised in the first Asymptomatic Carotid Surgery Trial (ACST-1) to CEA or best medical therapy (BMT). There was no difference in 10 year rates of dementia (CEA 6.7% vs. 6.6% with BMT) or at 20 years (14.3% [CEA] vs. 15.5% [BMT]), suggesting that CEA did not prevent dementia vs. BMT (hazard ratio 0.98, 95% confidence interval 0.75–1.28; p = .89).

Discussion

ACS is associated with significant cognitive impairment, but whether this supports a direct aetiological role, or a marker for something else, remains unknown. There is no evidence that CEA/CAS prevents late dementia. The 2023 ESVS guidelines have not changed its recommendation compared with the 2017 version.

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A recently published systematic review and baseline data from CREST-2 suggest that asymptomatic carotid stenoses are “significantly associated” with cognitive impairment.

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Apart from a possible haemodynamic aetiology, there is no current evidence that asymptomatic carotid stenoses can cause cognitive impairment via silent cortical infarction (lack of data), silent lacunar infarction (most involve small vessel disease), silent embolisation (no corroborative data), or white matter hyperintensities on magnetic resonance imaging (most involve small vessel disease).

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A recently published systematic review noted that 69% of patients undergoing carotid interventions had no change in late cognitive function. However, while another 25% had no significant change in late cognitive function overall, there was improvement in1–2 individual tests of cognition.

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ACST-1 showed no evidence that dementia rates were reduced in patients undergoing carotid endarterectomy (vs. best medical therapy) at 10 and 20 years post-randomisation.