Syndromic validity of apathy in Alzheimer's disease

Objective: The study examined the usefulness and clinical correlates of spe cific diagnostic criteria for apathy in Alzheimer's disease. Whereas apathy is a frequent behavioral change in patients with Alzheimer's disease, the lack of standardized diagnostic criteria may explain the wide discrepancies in estimates of the frequency and demographic and clinical correlates of a pathy. Method: A consecutive series of 319 patients who met the criteria for proba ble Alzheimer's disease established by the National Institute of Neurologic al and Communicative Disorders and Stroke and the Alzheimer's Disease and R elated Disorders Association, 117 patients who met the DSM-IV criteria for depression without dementia, and 36 healthy individuals were assessed with a structured psychiatric interview. On the basis of modified Marin's criter ia for apathy, they were classified into groups with or without apathy. Results: Apathy was diagnosed in 37% of the 319 Alzheimer's disease patient s, compared to none of the healthy comparison subjects. In 24% of the Alzhe imer's disease sample, apathy coexisted with either dysthymic disorder or m ajor depressive disorder, whereas 13% had apathy without depression. Apathy was diagnosed in 32% of the depressed nondemented patients, mostly in thos e with major depressive disorder. Apathy in Alzheimer's disease was signifi cantly associated with severe impairments in activities of daily living and cognitive functions, older age, and poor awareness of behavioral and cogni tive changes. Conclusions: This study provides partial validation of specific clinical cr iteria for apathy in Alzheimer's disease.