A new study suggests that a certain kind of molecules present in the blood could help in diagnosing Alzheimer's disease.

People who had amyloid in their brain, a peptide which is used in the diagnosis for Alzheimer's, were found to have a higher amount of fatty molecules that induce sleep in blood. Amyloid leads to the formation of plaque in the brain, and plaque accumulation happens many years before the symptoms begin to appear, according to the study published in the journal 'Alzheimer's & Dementia: The Journal of the Alzheimer's Association'.

"This is the first study in which lipid molecules produced in the brain are found in the blood, as amyloid deposition increases in Alzheimer's disease," said the lead author of the study, Dr. Cristina Legido-Quigley. For the study, researchers used a technique similar to throwing a fishnet to catch more number of molecules in the blood. This technique investigated if the molecules in the blood could be associated with amyloid in the brain.

They then generated a list of hundreds of molecules and found that fatty acid amides increased in line with amyloid in the brain. The team also found that these molecules were connected to brain shrinkage and memory loss. Dr. Cristina explained, "These fatty amides are known to be neuroprotective and to induce sleep. There is also evidence that amyloid accumulates in the brain with lack of sleep, so these molecules may be playing a role in clearing up toxic amyloid in the brain." "A blood test would be cheaper than measuring amyloid in the brain and easier to do than a spinal tap," she added.