When Is Alzheimer’s Not Alzheimer’s?
In the past, using the terms “Alzheimer’s disease” and “dementia” interchangeably was common. Now there is rising appreciation that a variety of diseases and disease processes contribute to dementia.
“Recent research and clinical trials in Alzheimer’s disease have taught us two things: First, not all of the people we thought had Alzheimer’s have it; second, it is very important to understand the other contributors to dementia,” she said.
For years, members of the scientific community have noticed that a large number of people who died in advanced age had symptoms of dementia without the telltale signs of amyloid or another common culprit, tau, in their brains at autopsy. Emerging research seemed to indicate that the protein TDP-43 contributed to that phenomenon.
“More than 200 different viruses can cause the common cold,” said Dr.
A group of international researchers co-chaired by Nelson and Silverberg set out to define diagnostic criteria and other guidelines for advancing future research into this newly-named dementia, called LATE.
LATE, which tends to appear in the oldest-old, may seem the same as Alzheimer’s to the lay person, but the disease inside the brain looks very different. The incidence of LATE is almost as prevalent among the oldest-old as Alzheimer’s.
The group’s work, published on
Nelson likens the committee’s work to Benjamin Franklin’s “discovery” of electricity.
“People had seen lightning before of course, but Franklin helped formalize a concept that augmented our ability to study electricity,” he said. “By developing a sense of scientific focus around these data, we hope to jump-start a broad field of work to advance our understanding of this form of dementia and, ultimately, to open new opportunities for treatment.
Most importantly, Nelson added, it’s time to stop thinking of dementia as a “one-size-fits-all” disease.
“LATE probably responds to different treatments than AD, which might help explain why so many past Alzheimer’s drugs have failed in clinical trials,” he said. “Now that the scientific community is on the same page about LATE, further research into the ‘how’ and ‘why’ can help us develop disease-specific drugs that target the right patients.”