Tau-load in the lingual gyrus impacts anxiety levels during the COVID-19 pandemic in participants of longitudinal observational studies in aging

ABSTRACT

Background By obtaining a better grasp on the impact of the COVID-19 pandemic on individuals with cognitive impairment, this knowledge could be used to improve the delivery of information to this particular group. We aimed to assess the relationship between tau deposition and the change in anxiety levels, before and during the pandemic. We hypothesized that since the pandemic, higher tau loads would lower the change in anxiety. Furthermore, we expected these anxiety levels not to be associated with COVID-19 related stress in participants with cognitive decline. Methods 63 participants of the Translational Biomarker of Aging and Dementia (TRIAD) cohort (cognitively healthy, N=38;cognitively impaired, N=25, of which 7 had dementia due to Alzheimer?s disease), were assessed to evaluate their individual change in anxiety levels (GAD-7). This was done at three different timepoints, of which the latest fell during the COVID-19 lockdown period. Two rates of change, one before and one during the pandemic, were determined using the following definition (next timepoint ? current timepoint)/time difference. In addition, at the latest timepoint, subjective stress due to COVID-19 was measured using the Montreal Assessment of Stress related to COVID-19 (MASC). To assess the levels of tau, standard uptake value ratios (SUVR) from previously obtained [18F]MK-6240 PET-scans were used. Results [18F]MK-6240 tracer binding in the lingual gyrus was negatively associated with the rate of change in GAD-7 scores after correcting for age, sex, years of education and the presence of APOE ε4, but only in cognitively impaired individuals during the pandemic (fig 1A). In addition, the GAD-7 score at the latest timepoint was associated with stress related to COVID-19, but only in cognitively healthy individuals (fig 1B and 1C). Conclusions The presence of tau in the lingual gyrus negatively affected the rate of change in GAD-7 scores during the COVID-19 pandemic in individuals with cognitive impairment. This could indicate that information pertaining to the pandemic does not reach these individuals in an efficient manner. The missing association between COVID-19 induced stress and the latest GAD-7 scores in these individuals is a further indication of this.