This study was designed to determine the effect of carotid endarterectomy/angioplasty on early (baseline vs. 3 months) and late (baseline vs. >5 months) cognitive function in patients with asymptomatic lesions.
This systematic research included 31 non-randomized studies.
Regarding the immediate post-operative period, 24 of these papers reported significant improvement in cognitive function; one study reported significant deterioration; three showed mixed results (some scores improved and others worsened), and the rest showed no changes.
In the late post-operative period (that is, well after endarterectomy or angioplasty), one study reported worse cognitive function, another showed significant improvement, some obtained mixed results, and most showed no change from baseline.
These results showed a similar distribution when comparing small studies with larger ones, controlled vs. uncontrolled studies, studies that used endarterectomy vs. others that used angioplasty, and studies with longer or shorter follow-up.
Intervention, whether it be endarterectomy or angioplasty, rarely improves long-term cognitive function (<2%). However, it rarely makes it worse (in fact, magnitude is similar: 2%).
In the long term, the vast majority of papers (69%) could not prove an improvement in cognitive function. Only a few studies indicated improvement. The rest reported no change.
Until we have new papers that better identify the most vulnerable patients (with poor functional reserve) or provide clear evidence that silent embolism from a diseased carotid artery does indeed lead to cognitive impairment, we will remain in a sea of speculation.
Original title: Effect of Carotid Interventions on Cognitive Function in Patients With Asymptomatic Carotid Stenosis: A Systematic Review.
Reference: Stefano Ancetti et al. Eur J Vasc Endovasc Surg. 2021 Aug 30;S1078-5884(21)00604-3. Online ahead of print. doi: 10.1016/j.ejvs.2021.07.012.