Small concomitant vascular lesions do not influence rates of cognitive decline in patients with Alzheimer disease

Objective: To determine the relation between concomitant small cerebral infarction and clinical progression of Alzheimer disease (AD). Design: A retrospective clinicopathologic study of patients with AD. Methods: We searched the databases of the University of California, San Diego, Alzheimer's Disease Research Center. La Jolla, for patients with an autopsy diagnosis of definite PID with or without a concomitant small cerebral infarction. Clinical and neuropsychologic data obtained during longitudinal follow-up were available for 201 subjects with AD neuropathologic features and 36 with AD and concomitant cerebral infarcts (volume, <10 cm(3)). The rates of cognitive decline on the Mini-Mental State Examination and the Dementia Rating Scale were each calculated and compared between the 2 groups. Results: The age at death was significantly (P=.05) higher and the Braak stage was lower in patients with mi red AD and infarct pathological features compared with those with AD pathological features only. The rate of cognitive decline over time was not significantly (P greater than or equal to.20 for all) different between the 2 groups. There was a trend for the presence of a cerebral infarct to be associated with more severe clinical dementia (P=.08) as measured by the Dementia Rating Scale, but no such trend for the Mini-Mental State Examination. Conclusion: This clinicopathologic correlation study suggests that concomitant small cerebral infarcts with a total volume of less than 10 cm(3) do not significantly influence the overall rate of global cognitive decline in patients with AD.