Epidemiological studies showed that COVID-19 increases risk of Alzheimer's disease (AD). However, it remains unknown if there is a potential genetic predispositional effect. The objective of this study was to examine potential effects of genetic susceptibility of COVID-19 on the risk and progression of AD. In particular the authors performed a non-overlapping 2-sample Mendelian randomization (MR) study using summary statistics from genome-wide association studies (GWAS). Two-sample Mendelian randomization (MR) analysis of over 2.6 million subjects was used to examine whether genetic susceptibility of COVID-19 is not associated with the risk of AD, cortical amyloid burden, hippocampal volume, or AD progression score. Additionally, a validation analysis was performed on a combined sample size of 536,190 participants. Conerning the results, the authors show that the AD risk was not associated with genetic susceptibility of COVID-19 risk (OR = 0.98, 95% CI 0.81-1.19) and COVID-19 severity (COVID-19 hospitalization: OR = 0.98, 95% CI 0.9-1.07, and critical COVID-19: OR = 0.98, 95% CI 0.92-1.03). Genetic predisposition to COVID-19 is not associated with AD progression as measured by hippocampal volume, cortical amyloid beta load, and AD progression score. These findings were replicated in a set of 536,190 participants. Consistent results were obtained across models based on different GWAS summary statistics, MR estimators and COVID-19 definitions. The authors concluded that their findings indicated that the genetic susceptibility of COVID-19 is not associated with the risk and progression of AD.
Ding P, Gurney M, Perry G, Xu R. Association of COVID-19 with Risk and Progression of Alzheimer's Disease: Non-Overlapping Two-Sample Mendelian Randomization Analysis of 2.6 Million Subjects. J Alzheimers Dis. 2023 Nov 18.
Doi: 10.3233/JAD-230632.