The research is accompanied by an editorial from Dr Jonathan Schott, who has previously been funded by Alzheimer's Society.
Researchers studied 311 people in their 70s and 80s with no cognitive problems. PET scans were used to look at amyloid plaques or tangles in the brain, which occur in Alzheimer's. An MRI brain scan was used to study metabolites, or by-products created by normal brain processes.
1 in 3 participants had high levels of amyloid plaques, and they were also more likely to have abnormal levels of certain metabolites that are known to be altered in Alzheimer's disease.
Alzheimer's Society comment:
'This study is interesting as two early markers for Alzheimer's disease have been found in a group of people with no symptoms. Detecting more than one indicator years before symptoms appear could lead to more reliable diagnosis techniques that can improve lives and advance research. However, it is too early to tell if this group of people will develop the disease.
'Diagnosis before symptoms are experienced is becoming the Holy Grail in our race to treat the disease. New breakthroughs are being made every day but much more funding is urgently needed if we are to defeat Alzheimer's.'
Dr Susanne Sorensen
Head of Research