Is It Really Alzheimer's?

News yesterday that Alzheimer's may be misdiagnosed in sizeable numbers, based on a limited study of brain autopsies, should make us wonder if Alzheimer's is as prevalent as advertised. Increasingly, the general public does not distinguish between Alzheimer's and other form of dementia. That's probably because Alzheimer's is the most common and widely known forms of dementia. But medical professionals certainly do know the differences, because the treatment for one form can be radically different for another, and misdiagnosing can cause other health complications.

From an article in U.S. News & World Reports:

The researchers autopsied the brains of 426 Japanese American residents of Hawaii who had been, on average, 87 years old when they died. About half had been diagnosed with some form of dementia, typically Alzheimer's.

Among those whose brain lesion profile did not confirm an Alzheimer's diagnosis, the investigators did uncover evidence of other forms of dementia, including Lewy body dementia, vascular dementia, generalized brain atrophy and a range of non-specific forms.

The chances of a misdiagnosis, the researchers found, appeared to rise with the patient's age.

Here's a great primer on dementia from the National Instistute of Neurological Disorders and Stroke: Dementia Information Page