Hippocampal atrophy correlates with clinical features of Alzheimer diseasein African Americans

Context: Imaging measurements may aid in the characterization and diagnosis of patients with Alzheimer disease (AD). Most research studies, however, h ave been performed on predominantly white study groups despite the fact tha t there may be biological differences in AD between African American and wh ite patients. Objective: To measure hippocampal volume in African American patients with AD and to correlate these measurements with the presence of AD and neuropsy chological test performance. Design: Survey study. Setting: Academic center. Participants: Fifty-four healthy African American subjects and 32 African A merican patients with AD were studied. Hippocampal volumes were measured in all subjects from magnetic resonance images using established methods. Main Outcome Measure: Correlations were assessed between hippocampal volume and demographic variables, clinical group membership, and neuropsychologic al performance. Results: The hippocampi of patients were atrophic with respect to those of healthy subjects (P < .01). Significant direct correlations were present be tween hippocampal volumes and performance on several different neuropsychol ogical tests (r >0.5 and P < .01 for every test evaluated) when patients an d healthy subjects were combined. Conclusions: Hippocampal atrophy is a feature of AD in African Americans as it is in white subjects. The neuropsychological-hippocampal volume correla tions indicate that hippocampal volume measurements do represent a measure of the structural substrate of functional impairment in AD.