[Depression in the aged patient: bibliographic review]

The purpose of this review is to describe the diverse aspects of depression in the elderly. The bibliographical research includes epidemiology, theoretical models, diagnosis and treatment. Many studies emphasize the need for an accurate diagnosis, given the risk of unrecognized depression. The therapeutic trial is used when there is uncertainty about the diagnosis, especially whether it is depression or dementia. A treatment and a long follow-up are necessary to prevent relapses and recurrences.