Trastorno cognitivo en la estenosis carotídea: Evaluación neuropsicológica y efecto del tratamiento quirúgico

Abstract

Introduction: Cognitive decline after an acute cerebrovascular event is frequent, and it has been estimated that around 55% of stroke subjects develop episodic memory deficits, 40% executive function deficits and up to 23% language function deficits. Carotid artery stenosis (CAS) causes between 20% and 30% of ischemic cerebral infarctions. In recent years, diagnosis and surgical treatment of CAS has been a relevant focus of interest in the medical literature. However, the contribution of CAS per se to cognitive function in asymptomatic patients or in patients with transient ischemic attacks is poorly understood. The objectives of the studies reported in the present Doctoral Thesis were as follows: 1) to assess whether persons with severe CAS (> 70%) without cerebrovascular symptoms and without dementia showed a greater cognitive decline as compared to healthy individuals; 2) to describe which cognitive functions were altered and whether there were cognitive differences according to severity of stenosis, side of surgical repair, and presence or absence of neurological symptoms; and 3) to identify a predictive clinical and neuropsychological profile for patients which will present a improvement of their cognitive profileg after revascularization. Study 1 Method: 106 subjects were included: 53 patients with severe CAS and without dementia and 53 healthy controls matched by age, sex, education level and manual dominance. Cognitive assessment was performed using the Repeatable Battery Assessment for Neuropsychological Status (RBANS). Results: It was found that patients with CAS showed a lower cognitive performance than controls in attention, verbal memory, visuospatial capacity and verbal fluency. Analysis according to the degree of stenosis showed that patients with higher degree of total CAS showed lower scores on learning and memory. Also, patients with left CAS showed lower performance on frontal cognitive tasks as compared to patients with right CAS. Study 2 Method: 70 patients who were scheduled for carotid revascularization were evaluated on two occasions, one week before the intervention (baseline) and one year after the surgical procedure using a large battery of neuropsychological tests normalized for the Spanish population. Results: 38.6% of patients were classified as “responders” as they presented an improvement of at least one standard deviation in at least two tests after the surgical procedure. Predictive factors of positive response were younger patient’s age as well as absence of neurological symptoms, and no detection of cerebral atrophy and small-vessel lesions on imaging studies. Cognitive performance at 12 months after surgery remained stable in all areas evaluated, except for language. A worse performance in visuospatial functions and executive tasks at 12 months was observed in patients with neurological symptoms as compared with asymptomatic patients. Patients undergoing revascularization procedures of the left side showed worse cognitive performance at 12 months after the surgical procedure in verbal and visual attention as well as in verbal fluency. Conclusions: Patients with severe CAS showed a lower baseline cognitive status as compared with a general population of the same sociodemographic characteristics. Cognitive decline was associated with the degree of CAS. Patients without neurological symptoms, of younger age and without white matter periventricular lesions and cerebral atrophy showed a better cognitive response at one year after carotid artery revascularization.

Date of Award	8 Sept 2017
Original language	Spanish
Awarding Institution	Hospital de la Santa Creu i Sant Pau
Supervisor	Antonio Bulbena Vilarrasa (Tutor) & Maria Teresa Garolera Freixa (Director)