Impact of COVID-19 on AD Occurrence: A Biracial Intergenerational Population Study

The Chicago Health and Aging Project (CHAP) has made several significant contributions to Alzheimer's disease and related dementias (ADRD) epidemiology. These areas include racial disparities, prevalence, and incidence of dementia trends, social, lifestyle, vascular, genetic risk factors, and neuroimaging and blood biomarkers in a large population-based community study of African Americans (AAs) and European Americans (EAs). Using the older CHAP parent and the ongoing midlife offspring cohorts, we will test several novel and innovative hypotheses on the impact of COVID-19 on ADRD, MCI, cognitive decline, and structural MRI brain injury. By extending the awarded NIA NOSI Administrative Supplement, the intergenerational study provides significant advantages by investigating: (1) the direct effect of SARS-CoV-2 infections amongst those with higher inflammatory cytokines, especially in families with a high risk of COVID-19 transmission, which leads to adverse cognitive outcomes; and (2) an indirect effect of COVID-19 outbreak-imposed changes in physical and cognitive activities, social engagement, and vascular risk factors in a shared family environment in diverse communities. To address this scientific area of research, we propose to conduct a biracial population-based community study of 4,000 older CHAP parents with two population cognitive assessments and detailed clinical evaluations for ADRD in 1,200 participants with the following specific aims: (1) Estimate the 2020 US census demographic adjusted overall and demographic-specific (age, race/ethnicity, and gender) prevalence and incidence of ADRD, MCI, and dementia likelihood and test whether the prevalence and incidence have changed before and after COVID-19. Also, test whether the 5-year risk of ADRD among high-risk AA parents has high-risk offspring compared to EAs; (2) Examine the change in physical and cognitive activities, social engagement, BMI, and hypertension from pre- to post-COVID and the impact of these changes on the risk of ADRD, MCI, cognitive decline, and MRI brain injury. Also, test whether these associations are higher by age, sex (males vs. females), and among AA parents and offspring compared to EA parents and offspring; (3) Test whether participants with SARS-CoV-2 RNA infections and serology antibodies and elevated concentrations of inflammatory cytokines among those with higher vascular risk factors have a higher risk of ADRD, MCI, cognitive decline, and structural MRI brain injury. Also, test whether these associations are higher among AA parents and offspring compared to EAs. This proposal has an enormous public health impact in developing preventive strategies and therapeutic studies on the impact of COVID-19 on population health across generations from midlife to late-life in a diverse population with socially disadvantaged AA minorities.