Clinico-neuropathological correlation of Alzheimer's disease in a community-based case series

OBJECTIVES: Most clinico-neuropathological correlative studies of Alzheimer 's Disease (AD) are based on research cohorts that are not necessarily gene ralizable to patients seen in the general medical community. In this study, we examine the accuracy of the criteria used in diagnosing AD in a communi ty-based case series of patients with memory complaints. DESIGN AND PARTICIPANTS: Clinical and neuropathological diagnoses were obta ined from 134 patients evaluated for dementia who subsequently underwent au topsy. SETTING: Subjects who exhibited new symptoms of dementia and were enrolled in the University of Washington/Group Health Cooperative Alzheimer's Diseas e Patient Registry were eligible for this study. MEASUREMENTS: Clinico-pathological correlation was performed using NINCDS-A DRDA (National Institute of Neurological and Communicative Disorders and St roke and the Alzheimer's Disease and Related Disorders Association) and CER AD (Consortium to Establish a Registry for Alzheimer's Disease) criteria. RESULTS: Ninety-five of the 134 cases studied met CERAD neuropathological c riteria for AD. The sensitivity of NINCDS-ADRDA "probable AD" was 83 % (dia gnosing AD correctly) and overall clinical diagnostic accuracy was 75%. How ever, there was a high rate of additional neuropathological findings. Only 34 of the 94 cases had pure AD on neuropathology, whereas the remainder fre quently had coexisting vascular or Parkinson's disease lesions. CONCLUSIONS: This study of a large series of community-based incident demen tia cases provides a way of judging the adequacy of currently available cli nical diagnostic criteria. It also shows that co-existing neuropathological findings are common in community-based A.D.