OBJECTIVES: While the acute impact of COVID-19 on mental health has been documented, less is known about its long-term consequences on cognitive health. We investigated the association between worsening depressive and anxiety symptoms during the pandemic with the risk of subjective memory decline over a three-year follow-up.
STUDY DESIGN: Prospective cohort study.
METHODS: We analyzed data from 682 adults participating in the PAMPA cohort, a longitudinal study in southern Brazil. Changes in depressive and anxiety symptoms were assessed at baseline (2020) and during the pre-pandemic period retrospectively. Subjective memory decline was self-reported in the fourth follow-up (2023). Robust Poisson regression was used to estimate associations. Inverse probability weighting was used to estimate selection bias.
RESULTS: Over follow-up, 51 % (95 %CI: 47.1 %-54.6 %) of participants reported subjective memory decline. Worsened depressive (RR: 1.33; 95 %CI: 1.21-1.64) and anxiety (RR: 1.36; 95 %CI: 1.28-1.44) symptoms were associated with a higher risk of subjective memory decline. Each one-point increase in depression (RR = 1.04; 95 % CI: 1.03-1.05) and anxiety (RR = 1.02; 95 % CI: 1.01-1.03) symptoms was linked to a 4.3 % and 2.4 % increase in the risk of subjective memory decline. Associations remained robust after adjusting for COVID-19 status and other potential confounders, including depressive and anxiety symptoms at follow-up. Results were consistent in sensitivity analyses excluding participants with long COVID.
CONCLUSION: Worsening mental health during the COVID-19 pandemic predicted subjective memory decline three years later. Our findings underscore the importance of mental health support as a public health strategy to preserve long-term cognitive function, particularly after large-scale crises.
