Background Carotid artery stenosis may contribute to cognitive impairment through chronic hypoperfusion and subclinical ischemic injury. Although carotid endarterectomy (CEA) and carotid artery stenting (CAS) reduce stroke risk, their cognitive effects remain unclear. We conducted a systematic review and meta-analysis to evaluate cognitive outcomes after these interventions.

Methods Following PRISMA guidelines, we searched PubMed, Embase, Web of Science, and the Cochrane Library from January 2000 to November 2025. Eligible studies reported cognitive outcomes after CEA or CAS, either alone or in direct comparison. Random-effects meta-analyses were performed for Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) outcomes. Single-arm studies were analyzed using standardized mean change, and head-to-head studies using mean difference. Outcomes were stratified by intervention type and follow-up interval (0–6 months and >6 months). Domain-specific cognitive outcomes were summarized qualitatively. Risk of bias was assessed using RoB-2, ROBINS-I, and the Newcastle-Ottawa Scale.

Results Sixty-eight studies including 4,659 patients met inclusion criteria; 27 contributed to meta-analysis and 41 to qualitative synthesis. MMSE showed no significant early change after either intervention, while CAS showed significant improvement at >6 months. MoCA improved significantly after both CEA and CAS at early and late follow-up, although heterogeneity was high. Head-to-head analyses found no significant difference between CEA and CAS for MMSE or MoCA, but these comparisons were limited by small sample sizes. Domain-specific outcomes were mostly stable, with improvements most often reported in memory, attention, executive function, and processing speed.

Conclusions Carotid revascularization may be associated with improved cognitive outcomes, particularly on MoCA, but results are heterogeneous and largely observational. Comparative evidence does not show a clear cognitive advantage of CEA or CAS. Future studies should use standardized cognitive testing and adequately powered direct comparisons.

The authors have declared no competing interest.

No internal or external funding was provided for or during the generation of the content of the manuscript.

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Literature Addition/Influence on Clinical Practice: This review adds a comprehensive synthesis of cognitive outcomes after carotid endarterectomy and carotid stenting, showing modest global cognitive improvement in single-arm studies but no clear difference between procedures in head-to-head analyses. It also highlights that MoCA may be more sensitive than MMSE and that domain-specific effects are variable. Clinically, these findings support considering cognition as a relevant outcome in carotid disease, while emphasizing the need for standardized neuropsychological testing and prospective comparative studies before cognitive benefit can be used to guide procedural choice.

All data contained within the manuscript is available upon request from the primary author