By Julian Fisher, MD

"Clarifying" and "dementia" may seem to be terms in conflict, but they allow me to shed some light on my last post -- and a response to those who wrote in with valid comments and concerns.

In general and from a public health/health economics standpoint, it is unreasonable to undertake mass screenings for a disease that has no effective treatments.  Early diagnosis cannot initiate early treatment, prevention or anything...with one important exception that I neglected to mention, and for which I apologize.

Patients beginning the deterioration of a disease like Alzheimer's are still often active in life and business, in social activities and philanthropic activities, all of which may suffer as the neurodegeneration proceeds.  These patients are part of families and communities, with multiple interdependencies.

If there is some concern that someone is suffering an evolving mild cognitive impairment, an early step toward a potentially diagnosable dementia like Alzheimer's, and that person's loss of function and judgment may adversely affect others by bad personal or business decisions (family social or financial issue, business investments, charitable donations), there may well be justification for an attempt at early diagnosis.

One does have to be cautious, though, at this early stage, since the newly reliable tests are new and their reliability has only been proven in relatively small studies.  Sitting on a three-legged stool is comforting -- as long as all three legs are solid.

Julian Fisher, MD is a Boston-based neurologist and medical information entrepreneur.