Differences by sex in early-onset Alzheimer's disease

Biological sex, that is, being born male or female, can influence different aspects of early-onset Alzheimer's disease (symptoms seen before the age of 65).

This is suggested by a recently published investigation carried out by researchers from the Clínic-IDIBAPS. The study shows that there are differences between the sexes when early-onset Alzheimer's disease is diagnosed. Women experience more generalised brain atrophy and greater cognitive impairment than men, compared to healthy people of the same sex. This affects memory loss, with higher levels of tau protein in cerebrospinal fluid (a key biomarker for the diagnosis of Alzheimer's disease). Thus, biological sex could be a factor that influences susceptibility to developing the disease, including its evolution. However, this research has some limitations, such as the very small number of people studied. Therefore, more extensive studies are needed in this line of research to take into account other factors; for example, individual hormone history.

The fact that Alzheimer's disease is more frequent in women suggests that the female sex is a risk factor. Identifying how sex influences different Alzheimer's disease biomarkers may be important in improving diagnosis. Also, analysing how these substances change in line with different presentations of the pathology is essential for better understanding of the pathophysiology of this disease.

The study consisted of 106 participants, of whom 62 had early-onset Alzheimer's disease and 44 were healthy, from the Alzheimer's and other cognitive disorders Unit at the Hospital Clínic, Barcelona.

Alzheimer's disease is today the leading cause of neurodegenerative dementia worldwide, with over 50 million people affected. Apart from memory loss, the neurodegeneration caused by Alzheimer's disease also interferes with the functioning of other brain areas responsible for cognitive tasks, such as language, orientation and behaviour.

The study results suggest that there are sex differences at the time of diagnosis. These differences could be important in the prevention of Alzheimer's disease, in its diagnosis and in monitoring the response to new drugs in the experimental phase. However, more studies are needed on precision medicine in patients with early-onset dementia.

REFERENCE ARTICLE:

José Contador, Agnès Pérez-Millan, Núria Guillén, Jordi Sarto, Adrià Tort-Merino, Mircea Balasa, Neus Falgàs, Magdalena Castellví, Sergi Borrego-Écija, Jordi Juncà-Parella, Beatriz Bosch, Guadalupe Fernández-Villullas, Oscar Ramos-Campoy, Anna Antonell, Nuria Baragalló, Raquel Sánchez-Valle, Roser Sala-Llonch and Albert Lladó. Sex differences in early-onset Alzheimer's disease. Eur J Neurol 2022, 19, 3623-3632.

INFORMATION DOCUMENTED BY:

Dr. Agnès Pérez-Millan. Physicist and researcher at the Alzheimer's and other cognitive disorders Unit, Hospital Clínic, Barcelona. Researcher at the IDIBAPS Group on Alzheimer's Disease and other cognitive disorders.

Dr. Albert Lladó Plarrumaní. Neurologist at the Alzheimer's and other cognitive disorders Unit, Hospital Clínic, Barcelona.