Mental health and sociodemographic influences during COVID-19: Longitudinal findings from Iceland.

The COVID-19 pandemic introduced numerous stressors and challenges that have had profound implications for mental health. This study examined the effects of the pandemic on mental health among Icelandic adults (n = 1766), using longitudinal survey data spanning three waves of data collection from 2019 to 2022. Symptoms of depression, anxiety, and stress increased from the beginning of the pandemic to the second time point, approximately one year into the pandemic, coinciding with reductions in happiness and social support. By the third time point, mental health remained slightly poorer than pre-pandemic levels, even after all COVID-19-related restrictions had been lifted. Unlike some other countries, COVID-19 infections in Iceland did not rise significantly until after the summer of 2021. Overall, participants perceived that the pandemic most adversely affected their social relationships and mental health. Prolonged periods in quarantine were predictive of these perceptions, albeit effect sizes were small. During the pandemic, women and younger participants reported slightly poorer mental health, while social support predicted better mental health outcomes. These results show that large societal stressors can significantly impact the mental health of populations. While social support is a prominent predictor of better mental health, additional variables may be needed to explain these effects fully.