Depression in Alzheimer's disease and other dementias.

Much of our current knowledge about depression in Alzheimer's disease and other dementias is based on the 1991 National Institute of Health Consensus Development Panel on the Diagnosis and Treatment of Depression in Late Life, and its subsequent 1997 update. However, much research has taken place since these reports. This article summarizes this research, particularly research that has taken place in the past year. Comorbid depression is common in all types of dementia. It may, however, appear to be different from classic depression. Unlike classic depression, the depression found in dementia may result from anatomic damage to the brain. This is most clearly demonstrated in vascular depression. The implications of this are many. Treatments for depression are designed for classic depression. For those with vascular depression (and other depressions associated with dementia) treatments may not be as efficacious. Newer strategies, including agents not commonly thought of as antidepressants, may be needed.