EEG SPECTRAL ABNORMALITIES AND PSYCHOSIS AS PREDICTORS OF COGNITIVE AND FUNCTIONAL DECLINE IN PROBABLE ALZHEIMERS-DISEASE

We examined whether either psychotic features (e.g., delusions and hal lucinations) or EEG abnormalities are associated with more rapid progr ession of Alzheimer's disease (AD). AD patients with psychosis have ex hibited more EEG abnormalities than those without psychosis, and both abnormal EEG and psychosis have been noted to be predictors of functio nal and cognitive decline in AD. Ninety-five probable AD patients part icipating in a longitudinal study of dementia had an EEG and a semistr uctured psychiatric interview at baseline, Using EEG spectral analysis , we classified records as normal/abnormal based on the parasagittal m ean frequency. Patients with abnormal EEGs were more functionally (e.g ., Blessed Rating Scale for activities of daily living) and cognitivel y (e.g., Mini-Mental State) impaired than patients with normal EEG;, A D patients with psychosis were only more functionally impaired than pa tients without psychosis. A two-factor analysis showed no interaction between abnormal EEG and psychosis. In addition, using a Cox proportio nal hazard model adjusted for age and education, the presence of an ab normal EEG or psychotic symptom at study entry was associated with hig her risk of reaching severe cognitive and functional impairment during follow-up, Neither abnormal EEG nor the presence of psychosis predict ed death, These results indicate that both abnormal EEG and psychosis are independent predictors of disease progression but not of physical survival.