Prestroke cognitive impairment: frequency and association with premorbid neuropsychiatric, functional, and neuroimaging features

BACKGROUND: Some patients with stroke have prestroke cognitive impairment (pre-SCI), but its etiology is not clear. The aim of this cross-sectional study was to assess the frequency of pre-SCI and its association with premorbid neuropsychiatric, functional, and neuroimaging features. METHODS: Patients hospitalized in stroke unit with an informant who could complete IQCODE (Informant Questionnaire for Cognitive Decline in the Elderly) were included. Pre-SCI was diagnosed if the IQCODE score was >3.3. Prestroke assessment also included NPI-Q (Neuropsychiatric Inventory Questionnaire), the basic Activities of Daily Living and Instrumental Activities of Daily Living scales, and the Clinical Dementia Rating scale. A multivariate logistic regression model was used to evaluate the association of pre-SCI with age, sex, education, arterial hypertension, atrial fibrillation, white matter lesions, cerebral microbleeds, and pathological medial temporal lobe atrophy. RESULTS: IQCODE was available in 474 of 520 patients (91.2%; 45% women; mean age 75.5±13.3 years). Pre-SCI had a prevalence of 32.5% and was associated with prestroke NPI-Q (pre-SCI absent versus present, 1.7±2.3 versus 5.5±4.9; P<0.001), Activities of Daily Living scale (0.3±0.8 versus 1.8±1.9; P<0.001), Instrumental Activities of Daily Living scale (0.6±1.3 versus 3.8±4.0; P<0.001), and Clinical Dementia Rating scale score (0.7±1.7 versus 7.2±6.2; P<0.001). In the 271 patients with a magnetic resonance imaging available, the multivariate logistic regression showed that age (odds ratio [OR], 1.05 [95% CI, 1.62-9.73]), white matter lesions (OR, 1.26 [95% CI, 1.003-1.58]), and a pathological medial temporal lobe atrophy score (OR, 3.97 [95% CI, 1.62-9.73]) were independently associated with pre-SCI. In the 218 patients with ischemic stroke, white matter lesions (OR, 1.34 [95% CI, 1.04-1.72]) and medial temporal lobe atrophy (OR, 3.56 [95% CI, 1.38-9.19]), but not age, were associated with pre-SCI. CONCLUSIONS: One-Third of patients admitted to a stroke unit have pre-SCI that is associated with preexisting neuropsychiatric symptoms and functional performance. White matter lesions and medial temporal lobe atrophy are associated with pre-SCI, suggesting that both small vessel disease and neurodegeneration might be involved in its etiology.