Review: delirium in the elderly: a comprehensive review.

Delirium is a common neuropsychiatric syndrome in the elderly characterized by concurrent impairments in cognition and behaviors. The etiologies for delirium are often multifactorial and are due to underlying medical illnesses and/or due to medication effect. The diagnosis of delirium is often missed in elderly patients and this condition may be mislabeled as depression or dementia.