Tracking population mental health before and across stages of the COVID-19 pandemic in young adults

The SARS-CoV-2 (COVID-19) pandemic has been associated with worsening mental health. Longitudinal studies have monitored changes in mental health from pre-pandemic levels, identifying critical points for mental health as COVID-19 restrictions evolve. Here we highlight changes in depression and anxiety in the UK from pre-pandemic across four pandemic occasions: April and June 2020, January, and July 2021 - corresponding to changes in COVID-19 restrictions. Data were from >5,000 27-29-year-olds from the Avon Longitudinal Study of Parents and Children (ALSPAC). We found that anxiety almost doubled throughout the pandemic compared to pre-pandemic levels and remained high until July 2021 when COVID-19 restrictions were fully lifted. Depression was lower than pre-pandemic levels in April 2020 but increased as the pandemic evolved until July 2021. Women, those with existing mental/physical health conditions and those with economic hardship were most at risk of sustained poorer mental health across the pandemic. Our results highlight the importance of longitudinal studies for tracking mental health during the COVID-19 pandemic and across virus suppression policy changes.