Experiences with depression in a dementia clinic

Of 317 consecutive cases seen in a dementia clinic, 19 (6%) had little or no objective evidence of cognitive impairment on clinical examination and extensive neuropsychological testing. Of the remaining 298 cases, 192 (64%) were diagnosed as probable or possible Alzheimer's disease (AD). Of the 19 nondemented cases, 8 (42%) were thought to have cognitive difficulty due to depression. In the AD group, only 4 cases (2%) were thought to be depressed and only 2 of the 4 met DSM-III-R criteria for major depression. There was no relationship between Hamilton Rating Scale for Depression scores and either cognitive or behavioral measurements of dementia severity, suggesting that the difference between the two groups was not due to underreporting by AD patients. The authors concluded that in a tertiary care setting, depression is a common cause of cognitive complaints in persons without organic disease and a rare cause of excess morbidity in AD.