A new BBRC study links Alzheimer's biomarkers to symptoms of anxiety and depression during confinement by Covid-19

According to the main results of this study from the study 'Pre-pandemic Alzheimer disease biomarkers and anxious-depressive symptoms during COVID-19 confinement in cognitively unimpaired adults', published in Neurology®, risk markers for Alzheimer's disease such as protein amyloid beta or neuroinflammation are related to increased symptoms of anxiety and depression during confinement by Covid-19.

The research has studied, using multivariate analysis regression models, the association between biomarkers related to Alzheimer's and sociodemographic factors, as well as the results of the hospital anxiety and depression scale questionnaire HADS (Hospital Anxiety and Depression Scale) during lockdown and before. The work has analysed the negative impact of the Covid-19 confinement on mental health in cognitively healthy people and has been carried out with 921 participants of the Alfa Study, promoted by ”la Caixa” Foundation. Of the total number of participants, results with biomarkers of Alzheimer's disease of 254 people have been examined.

The cohort participating in the study, enriched by risk factors, has made it possible to lay the foundations for a possible association between the pandemic and Alzheimer's. This association is important because it may lead to a worse clinical prognosis in people at risk of Alzheimer's after the pandemic. In a previous evaluation, the majority of study participants had standard levels of anxiety and depression and, in contrast, during the confinement 16.6% of the participants suffered an increase in anxiety, while 9.9% declared depressive symptoms. During the preclinical stage of Alzheimer's, there is an increase in symptoms of anxiety and depression that can accelerate the progression of the disease. "In this context, it was relevant to investigate the possible association between symptoms of anxiety and depression during confinement due to Covid-19 and biomarkers of Alzheimer's disease", explains Müge Akinci, BBRC researcher and lead author of the study.

The research has also had the collaboration of the University of Gotheburg, the Hong Kong Center for Neurodegenerative Diseases, Pompeu Fabra University, the Hospital del Mar Medical Research Institute and the CIBER for Fragility and Healthy Aging (CIBERFES), among others.

Gender, a risk factor

Research has also explored the role of stress and lifestyle changes (sleep, eating, drinking, smoking habits and medication use) during this period, as well as socio-demographic factors such as sex/gender differences and the mental health of caregivers. Differences have been observed between men and women regarding the hours of sleep during confinement and food consumption, as well as differences between caregivers and non-caregivers.  

Anxiety and depression pose an increased risk of developing cognitive impairment and Alzheimer's disease, and the prevalence observed in this study is higher among women. On the HADS scale, women scored higher than men for both anxiety and depression symptoms.

"In general, the results support the link between neuropsychiatric symptoms and the load of beta amyloid in the brain in the preclinical stage of Alzheimer's, especially in the case of women," declares Dr. Eider Arenaza-Urquijo, study researcher and team leader at the BBRC. "They show modest but significant changes and, therefore, it is appropriate that they be taken into account in the clinical field", she concludes. 

The findings of this study open the door to future research on the consequences of the pandemic on the mental health and clinical prognosis of people who are in the preclinical stage of this disease.