Provisional diagnostic criteria for depression of Alzheimer disease: rationale and background.

This review provides the rationale and background for the development of diagnostic criteria for depression of Alzheimer disease (AD), including risk factors and neurobiological correlates, epidemiology, and clinical characteristics, along with course, assessment, treatment, economics, a description of the criteria, and future research directions. Overall, there is substantial research to suggest that the depression that may co-occur with AD is different from other depressive disorders. Further research is needed to better define core symptoms, clinical course, and efficacy of treatments.