A patient's ability to identify smells can accurately discriminate between dementia associated with Alzheimer's disease or other forms of dementia, according to researchers in New York.

Their study included 60 patients, 20 per group, who met criteria for Alzheimer's, vascular dementia and major depression.

Each was given the Pocket Smell Test -- a three-item measure of odor identification -- and the Mini-Mental State Examination.

The researchers, reporting in the Journal of Neuropsychiatry, found that Alzheimer's patients scored significantly lower that those suffering from vascular dementia or major depression.

"Olfactory assessment may be of diagnostic utility in the differential diagnosis of Alzheimer's disease versus vascular dementia versus major depression in elderly patients," the researchers concluded.

Other Sources: Journal of Neuropsychiatry