“When both beta-amyloid and tau are present in the brain, it can no longer be considered a risk factor, but rather a diagnosis. A pathologist who examines samples from a brain like this, would immediately diagnose the patient with Alzheimer's”, says Rik Ossenkoppele, who is the first author of the study and is a senior researcher at Lund University and Amsterdam University Medical Center.

He explains that Alzheimer’s researchers belong to two schools of thought – on one hand, those who believe that Alzheimer's disease cannot be diagnosed until cognitive impairment begins. There is also the group that he himself and his colleagues belong to – ​​who say that a diagnosis can be based purely on biology and what you can see in the brain.

“You can, for example, compare our results to prostate cancer. If you perform a biopsy and find cancer cells, the diagnosis will be cancer, even if the person in question has not yet developed symptoms”, says Rik Ossenkoppele.

Recently, positive results have emerged in clinical trials of a new drug against Alzheimer's, Lecanemab, which has been evaluated in Alzheimer's patients. Based on this, the study from Lund University is particularly interesting, say the researchers:

“If we can diagnose the disease before cognitive challenges appear, we may eventually be able to use the drug to slow down the disease at a very early stage. In combination with physical activity and good nutrition, one would then have a greater chance of preventing or slowing future cognitive impairment. However, more research is needed before treatment can be recommended for people who have not yet developed memory loss”, concludes Oskar Hansson.