(May 27, 2009 - Insidermedicine) Brain changes typical of dementia are more likely to be found in relatively younger individuals with the disease compared with older ones, according to research published in the New England Journal of Medicine.

Here is some information about dementia:

•    It is a neurological condition in which intellectual functioning and memory are diminished

•    The most common form of dementia is Alzheimer's disease

•    Other causes of dementia include vascular disease in the brain and stroke

Researchers from the University of Cambridge and the University of Sheffield studied the brains of nearly 500 individuals who had died between the ages of 69 and 103. They determined the degree to which brain changes associated with dementia were actually present in those with the condition.

In those who died at age 75, there was a close relationship between brain changes linked with dementia and the actual presence of the disease. These associations were much less likely to be found among those aged 95. Only shrinkage of neocortical tissue, which is responsible for intellectual functioning, was consistently found in both older and younger patients.

We had a chance to speak with Professor Paul Ince, one of the authors of this study, who offered some further insight.

Today's research suggests that drugs for dementia that were developed based on brain changes found in younger patients with the disease may not be as effective in older patients.

For Insidermedicine in Depth, I'm Dr. Susan Sharma.