London, July 12 (IANS) Experts hope to develop brain scans to detect early symptoms of dementia that may surface 25 years before patients and their families notice any outward development.
Scientists believe that sufferers' brains and spines undergo miniscule changes when they are in their 30s and 40s.
An US study involved 128 people whose parents had an inherited form of Alzheimer's, meaning they were highly likely to get the disease themselves. Scientists carried out brain scans and tests on the fluid in their spine, the New England Journal of Medicine reports.
They noticed that some people underwent changes in the spinal fluid 25 years before they were likely to notice the first symptoms of Alzheimer's. They also spotted certain deposits in their brains - or 'plaques' - that showed up 15 years sooner than memory loss or confusion were expected to appear.
The researchers based the 25-year figure on the assumption that each person would begin showing signs of the illness at roughly the same age as their parents, according to the Daily Mail.
Experts point out that this inherited form of Alzheimer's - which is responsible for less than one percent of all cases - is different from the normal form of the disease.
Randall Bateman from Washington University School of Medicine in St. Louis said: A series of changes begins in the brain decades before the symptoms of Alzheimer's disease are noticed by patients or families, and this cascade of events may provide a timeline for symptomatic onset.
As we learn more about the origins of Alzheimer's to plan preventive treatments, this timeline will be invaluable for successful drug trials, added Bateman.