Impaired insight in Alzheimer disease: Association with cognitive deficits, psychiatric symptoms, and behavioral disturbances

Objective: The purpose of this study was to evaluate symptoms associated wi th impaired insight in patients with Alzheimer disease (AD). Background: Al though unawareness of deficits is common in AD. the relation of awareness t o psychiatric and behavioral disturbances has not been extensively studied. Method: We conducted a cross-sectional investigation of 91 patients with p robable AD according to the criteria of the National Institute of Neurologi cal and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association. Awareness of cognitive and functional defici ts was measured with the Inaccurate Insight item from the Neurobehavioral R ating Scale. Psychiatric and behavioral symptoms were measured using factor scores and individual items from the Neurobehavioral Rating Scale. Global cognitive deficits were measured using the Mini-Mental State Examination (M MSE). Results: Stepwise regression analysis showed that insight was associa ted with MMSE score, depression/anxiety factor score, and agitation/disinhi bition factor score. Variables not associated with awareness of deficits in cluded patient age, behavioral retardation factor score, verbal output dist urbance factor score, and psychosis factor score. Post hoc analyses showed a positive relation (i,e., greater insight. more symptomatology) between de ficit awareness and symptoms of depressed mood and anxiety. There was a neg ative relation (i.e.. greater insight, less symptomatology) between insight and symptoms of hostility, agitation, inattention, and tension. In a follo w-up stepwise regression analysis, increased deficit awareness was associat ed with a higher MMSE score, greater depressed mood, and decreased agitatio n. Conclusions: These findings suggest that patients with AD may experience symptoms of depressed mood in relation to increased awareness of decrement s in functioning. The data also indicate that patients with poor insight de monstrate greater agitated behavior. Consistent with previous research, imp aired insight was higher in the later stages of the illness.