New early changes identified in the brains of people at risk for Alzheimer's

Analysis of brain activity and a specific marker in the blood can help detect these early alterations in individuals without symptoms. The study included 76 participants without cognitive impairment, of whom 54 had a family history of the disease.

An international research led by the Complutense University of Madrid (UCM) points out an association between high levels of p-tau231 protein in blood and changes in brain networks in people without cognitive symptoms, but at risk of suffering Alzheimer'sThis discovery could facilitate the early identification of alterations associated with the disease.

The study included 76 participants without cognitive impairment, of which 54 had a family history. Although previous studies had already pointed to the increase of this protein in blood and its association with functional brain connectivity, this work provides, as a novelty, electrophysiological data measured with magnetoencephalography – a technique for recording non-invasive brain activity.

We have identified patterns of alterations in brain topology in cognitively healthy people with elevated levels of this protein in the blood.

Alejandra Garcia Colomo (UCM)

“We have identified patterns of alterations in brain topology in cognitively healthy people with elevated levels of this protein in their blood. These individuals have more integrated brain networks that are dependent on hubs, regions of high importance in the network,” he highlights. Alejandra Garcia Colomo, researcher at the UCM and author of the study published in Brain Communications.

García Colomo explains through a metaphor that, if we imagine our brain's communication as a map of connections, the objective of this study has been to understand how this map changes depending on the amount of p-tau231 protein in the blood.

The beginnings of the disease

What about the map of connections in cognitively healthy people with signs of pathology? Researchers have found alterations associated with elevated levels of p-tau231 in the blood. In this map, the connections are more saturated, which makes them more vulnerable and favours their damage.

“This research shows that even before symptoms appear, the brains of people with high levels of this biomarker show altered organization, increasing the vulnerability and dependence of certain key areas,” says García Colomo.

The results may be useful for developing early diagnosis tools for Alzheimer's and for evaluating treatments before clinical symptoms appear.

According to the authors, health professionals, researchers and pharmaceutical companies could use this information to identify individuals at risk and monitor the effectiveness of early interventions. In addition, the use of blood-based biomarkers and noninvasive imaging techniques facilitates broader and less expensive access to diagnostic tools.

More than 800 people affected in Spain

According to data from the Spanish Society of Neurology (SEN), Alzheimer's affects more than 800.000 people in SpainThe disease is the most common cause of dementia and is responsible for between 50 and 70% of total cases.

Together with other types such as vascular dementia, frontotemporal dementia, or Lewy body dementia, they already affect at least 1 in 10 people over 65 years of age and 33% of those over 85 years of age. In addition, according to the latest report from the National Institute of Statistics (INE), 8% of all deaths that occurred in 2023 in Spain were due to dementia.

Every year, around 40.000 new cases are diagnosed in Spain, more than 65% in women and 90% in people over 65 years of age.

“Dementia in general, and Alzheimer's disease in particular, has devastating consequences. Not only in terms of mortality, but also in morbidity and loss of quality of life, both for those who suffer from it and for their caregivers,” says Raquel Sánchez del Valle, Coordinator of the SEN Study Group on Behaviour and Dementia.

Every year are diagnosed in Spain about 40.000 new cases, more than 65% in women and 90% in people over 65 years of age. The SEN estimates that there is still a high underdiagnosis of this disease, especially in cases that are still mild.

Reference: Alejandra García-Colomo et al.: 'Minimum spanning tree analysis of unimpaired individuals at risk of Alzheimer's disease'. Brain Communications (2024)

Source: SINC Agency

principal photography: This finding may facilitate early detection of the disease. / Shutterstock

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