Behavioral Manifestations of Alzheimer’s Disease

Abstract

Neuropsychiatric manifestations are common in Alzheimer's disease (AD).Nearly all patients eventually exhibit some form of behavioral change.The Neuropsychiatric Inventory (NPI) is a valid and reliable means ofassessing behavioral alterations in patients with AD and otherdementias. The NPI assesses ten common types of behavioral changesevident in AD and has a caregiver distress scale allowing assessment ofthe amount of distress engendered by each of the behavioral changes.Investigations using the NPI and neuroimaging have demonstratedcorrelations between apathy and diminished medial frontal perfusion andpsychosis and disproportionately reduced perfusion of left medialorbital frontal, left anterior cingulate, left and right dorsolateralfrontal, left dorsal lateral parietal, left pulmonar, left ventralstriatum, and left cerebellum. High scores on the dysphoria subscale ofthe NPI correlate with reduced metabolism in the left and right superiorfrontal gyrus, middle frontal gyrus, inferior frontal gyrus, andanterior cingulate gyrus. The NPI also allows assessment of the responseof behaviors to psychopharmacological interventions. Reductions inbehavioral pathology have been demonstrated with cholinesteraseinhibitors (tacrine, donepezil, metrifonate, galantamine, andrivastigmine) as well as antipsychotic agents (olanzapine).