Association Between COVID-19 Infection and Subjective Cognitive Decline in Adults: A Cross-Sectional Online Survey Study.

Background: Cognitive impairment is the most common residual symptom following COVID infection, reported in approximately 22% of adults diagnosed with COVID-19. Subjective cognitive decline is considered a significant early indicator of the progression of Alzheimer's disease. There is limited research investigating subjective cognitive decline following COVID-19 infection.

Purpose: The purpose of this study was to examine the relationship between COVID-19 infection and subjective cognitive decline in adults.

Methods: In this comparative and cross-sectional study, data were collected via an online survey involving 98 adults diagnosed with COVID-19 and 317 adults never diagnosed with COVID-19. The mean age of participants was 30.2 ± 8.4 years, and 36.6% were female. The revised Everyday Cognition Scale was used to assess subjective cognitive decline. Data analysis included descriptive statistics, one-way analysis of covariance, and hierarchical multiple regression.

Results: After controlling for covariates, adults diagnosed with COVID-19 experienced significantly greater subjective declines in memory (P = .002), language (P = .002), organizational ability (P = .03), attention (P = .003), and global cognition (P = .007) than those never diagnosed with COVID-19. Furthermore, COVID-19 diagnosis was a significant predictor of worse subjective declines in these domains of cognition.

Conclusion: Findings highlight the associations between COVID-19 infection and subjective cognitive decline across various domains. These results underscore the need for longitudinal studies to explore the progression of cognitive decline. Early detection and management of cognitive dysfunction can prevent further deterioration of cognitive function.