They discover more presence of a protein in the brain of people with dementia

A working group of the Valdecilla Research Institute and the Neurology and Nuclear Medicine services of the Valdecilla Hospital, in Spain, advanced in the study of the presymptomatic phases of Alzheimer’s after discovering an increased presence of an amyloid protein in the brain of people with dementia.

This study, with nearly 20,000 people examined, describes the frequency of brain deposits of amyloid beta protein in healthy people and people with cognitive impairment from the age of 50.

This discovery directly affects the design of future clinical trials with anti-amyloid drugs.

The work is the largest carried out to date in this field, since it involves nearly 20,000 studied subjects, from 85 cohorts from different research centers around the world, including the hospital group and Idival, which make up the international initiative Amyloid Biomarker Study.

The research, led by Olin Janssen and Willemijn Jansen, from Maastricht University (The Netherlands), has just been published in Jama Neurology, the monthly medical journal of the American Medical Association.

Cerebral amyloid beta deposition, which is associated with Alzheimer’s disease, can be measured using a neuroimaging technique called amyloid Positron Emission Tomography (PET) or by determining amyloid beta protein (AB42) in fluid cerebrospinal (CL).

Amyloid appears in 24% of people with normal cognition, in 27% of those with subjective cognitive impairment, and in 51% of those with mild impairment.

The results are similar whether amyloid PET or CSF AB42 PET is used.

However, when cut-off points are recalculated based on the distribution of biomarker measurements, CSF AB42 detects 10% more cases of amyloid than PET, raising the prevalence of amyloid deposits in cognitively normal people to a third.

Furthermore, this prevalence of amyloid increases with age among people without dementia.

The study concludes that the very early stages of Alzheimer’s may be more frequent than previously estimated, which has “important” implications for strategies for the design and recruitment of clinical trials with anti-amyloid drugs, and for care planning policies. sanitary.