One-year Cognitive Outcomes Associated with Carotid Artery Stent Placement

Purpose

To assess relatively long-term (ie, 1 year) neurocognitive outcomes of patients undergoing carotid artery stent (CAS) placement with cerebral protection.

Materials and Methods

Sixty-two patients (19 symptomatic; mean age, 73 years) with significant carotid stenosis (≥ 70% for symptomatic patients, ≥ 80% for asymptomatic patients) underwent CAS placement with embolic protection. Cognitive function was assessed prospectively with use of a battery of standardized tests administered at baseline (1–5 days before CAS endovascular therapy) and at 3, 6, and 12 months after CAS placement. Diffusion-weighted imaging (DWI) was performed before the procedure and within 24 hours after CAS placement.

Results

Results of statistical modeling across occasions of measurement indicated significant main effects of occasion for the Dementia Rating Scale (DRS)–2 concept formation (P < .001), memory (P = .029), and total scores (P = .001); the DRS-2 total age- and education-corrected Mayo Older Americans Normative Studies score (P < .001); and the North American Adult Reading Test IQ score (P = .003). The vast majority of patients showed improvement or no change relative to baseline DRS-2 total scores at all time points. No significant relationship between DWI outcomes and cognition scores over time was found. Age influenced improvement on cognitive tests, whereas baseline symptom status did not.

Conclusions

Revascularization with a carotid stent and neuroprotection, at a minimum, left cognitive function unchanged in patients receiving a CAS, and in many instances improved it. The preliminary findings of this prospective pilot study should be confirmed with a larger, controlled trial.

Abbreviations: 3MS, Modified Mini-Mental State Examination, BDI, Beck Depression Inventory, CAS, carotid artery stent, CEA, carotid endarterectomy, DRS, Dementia Rating Scale, DWI, diffusion-weighted imaging, LES, Learning Efficiency Sum, LOT, Learning Over Trials, MOANS, Mayo Older Americans Normative Studies, NAART, North American Adult Reading Test, PRS, Percent Retention Sum, RAVLT, Rey Auditory Verbal Learning Test