The protective effects of Swedish COVID-19 pandemic strategies on adolescents' mental health: a longitudinal cohort study

Aim: The aim of this study was to investigate a cohort of Swedish eighth graders' mental health and experiences during the COVID-19 pandemic.Methods: Participants were 157 eighth graders recruited in junior high schools during 2020 who completed a depression questionnaire and a survey about their psychosocial health in relation to the COVID-19 pandemic, alongside a follow-up assessment in 2021. Analyses were conducted using latent change score and cross-lagged models.Results: Participants' depressive symptoms did not substantially increase during the COVID-19 pandemic. The level of depressive symptoms in 2020 was significantly associated with participants' perceptions of the pandemic in 2020 and spring 2021. Participants with higher depression scores reported worse experiences of the pandemic.Conclusions: The stable level of depressive symptoms among this cohort of eighth graders suggested that keeping schools open during a nationwide lockdown could mitigate some mental health consequences. Adolescents in this study with higher self-assessed depressive symptoms were more likely to experience increased depression after 6 months and had worse experiences during the pandemic than others. This suggests that the pandemic may not immediately affect mental well-being, but those at risk may be affected over time.