Dementia is an age‐independent risk factor for severity and death in COVID‐19 inpatients

Abstract

Introduction: Dementia has been associated with COVID‐19 prevalence, but whether this reflects higher infection, older age of patients, or disease severity remains unclear. Methods: We investigated a cohort of 12,863 UK Biobank community‐dwelling individuals > 65 years old (1814 individuals ≥ 80 years old) tested for COVID‐19. Individuals were stratified by age to account for age as a confounder. Risk factors were analyzed for COVID‐19–positive diagnosis, hospitalization, and death. Results: All‐cause dementia, Alzheimer's disease (AD), and Parkinson's disease (PD) were associated with COVID‐19‐positive diagnosis, and all‐cause dementia and AD remained associated in individuals ≥ 80 years old. All‐cause dementia, AD, or PD were not risk factors for overall hospitalization, but increased the risk of hospitalization of COVID‐19 patients. All‐cause dementia and AD increased the risk of COVID‐19–related death, and all‐cause dementia was uniquely associated with increased death in ≥ 80‐year‐old patients. Discussion: All‐cause dementia and AD are age‐independent risk factors for disease severity and death in COVID‐19.