COVID-19 symptoms are associated with higher variability in generalized anxiety and depression: results from a one-year longitudinal study in Spain

Background: The mental health impacts of COVID-19, particularly regarding anxiety and depression, are well-documented and more prevalent among women. This study aimed to assess the longitudinal effects of COVID-19 on anxiety, depression, and sleep conditions in a sample of Spanish adults. Methods: A total of 608 individuals completed biweekly anxiety, depression, and sleep questionnaires for over a year (July 2021-March 2023). Data on SARS-CoV-2 infection prior to questionnaire administration were also available. Respondents were classified into three groups based on prior SARS-CoV-2 infection and symptoms during a period preceding the administration of the questionnaire (no infection, infected asymptomatic, symptomatic). Means and variability scores for anxiety, depression, and sleep scores were tracked over time for each individual. Differences between the three groups were analysed, using generalized linear models to assess the impact of COVID-19 symptoms. Results: No significant differences in mean anxiety, depression, or sleep quality scores were observed among participants with no COVID-19 diagnosis, symptomatic infection, or asymptomatic infection. Women reported significantly higher anxiety and depression scores and poorer sleep quality than men (p < 0.001). Greater variability in anxiety and depression scores was found among symptomatic COVID-19 cases compared to non-infected individuals, while time since infection did not significantly influence mean scores or variability in any outcome. Conclusions: Individuals with COVID-19 symptoms exhibited greater variability in anxiety and depression scores, indicating increased psychological instability. Sleep quality was not significantly affected by COVID-19 symptoms. These findings underscore the importance of targeted interventions to address post-pandemic mental health challenges.