Coexisting Cerebral Infarction in Alzheimer's Disease Is Associated with Fast Dementia Progression: Applying the National Institute for Neurological Disorders and Stroke/Association Internationale pour la Recherche et l'Enseignement en Neurosciences Neuroimaging Criteria in Alzheimer's Disease with Concomitant Cerebral Infarction

OBJECTIVES: To determine whether patients with Alzheimer's disease (AD) and coexisting cerebral infarction (CI) that satisfy the National Institute for Neurological Disorders and Stroke/Association Internationale pour la Recherche et l'Enseignement en Neurosciences (NINDS‐AIREN) neuroimaging criteria for vascular dementia (VaD) progress faster than those who do not satisfy the neuroimaging criteria. DESIGN: Retrospective cohort study. SETTING: Multidisciplinary memory clinic in a tertiary hospital. PARTICIPANTS: One hundred thirty consecutive patients with AD, with or without CI, followed up regularly for more than 1 year. MEASUREMENTS: The patients were classified according to the distribution and severity of CI as defined according to the NINDS‐AIREN neuroimaging criteria into those with AD and no CI (AD‐N), those with AD and CI not fulfilling neuroimaging criteria (AD‐I), and those with AD and CI fulfilling neuroimaging criteria (AD‐V), and their differences in dementia progression were tested. The loss of independence, indicated by institution admission or a clinical dementia rating (CDR) score of 3, was defined as the endpoint for a poor outcome. RESULTS: The mean age was 75.8, and 68.5% were women. The initial Mini‐Mental State Examination (MMSE) score was 15.3±0.4, and the average duration of follow up was 30.4 months. Fifty‐four patients had reached study endpoint at the time of analysis. AD‐V (hazard ratio (HR)=3.1, 95% confidence interval (CI)=1.2–8.2), use of psychotropic drugs (HR=2.7, 95% CI=1.1–6.4), and initial MMSE score (HR=0.9, 95% CI=0.8–1.0) were independent predictors of poor outcome in the Cox regression model. CONCLUSION: In AD, co‐occurrence of CI with distribution and severity as defined in the NINDS‐AIREN neuroimaging criteria for VaD is associated with faster dementia progression.