Dementia after Three Months and One Year from Stroke: New Onset or Previous Cognitive Impairment?

OBJECTIVE Stroke is an important risk factor for dementia, but the exact mechanism involved in cognitive decline remains unclear. METHODS Patients were divided into 2 groups: poststroke dementia group (PSD) and poststroke nondementia group (PSND). Variables and neuroradiological hallmarks were compared between 2 groups at 3 months (114 subjects) and 1 year (105 subjects) after stroke. RESULTS Older age (OR 1.11, 95% CI 1.0-1.2; P < .05), education (OR .6, 95% CI .4-.8; P < .05), prestroke IQCODE (Informant Questionnaire on Cognitive Decline in the Elderly; OR .78, 95% CI .1-5.9; P < .05), premorbid apathy (OR 2.03, 95% CI 1.1-3.7; P < .05), and medial temporal lobe atrophy (MTLA) (OR 6.14, 95% CI 1.4-26.2; P < .05) were independently associated with PSD at 3 months after a cerebrovascular event, whereas at 1-year follow-up older age (OR 1.1, 95% CI 1.0-1.2; P < .05), prestroke IQCODE (OR .05, 95% CI .0-.9; P < .05), MTLA (OR 1.3, 95% CI 1.0-1.6; P < .05), and APACHE II (Acute Physiology and Chronic Health Evaluation; OR .6, 95% CI .4-.9; P < .05) were independently associated with PSD. CONCLUSIONS Acute cerebrovascular disease could not be the only one mechanism explaining PSD. Neurodegenerative pathology must be taken into account.