The COVID-19 pandemic: early life adversities, mental health trajectories and health service use

Abstract

The global spread of Coronavirus 2019 (COVID-19) posed significant threats to public health, and serious concerns have been raised about the adverse impact of the pandemic on population mental health. However, most existing studies have focused on mental health effects during the early stages of the pandemic or on specific high-risk groups, leading to a gap in understanding the long-term effects of the pandemic on mental health and health service use for the general population. Leveraging data sources from UK Biobank and the Icelandic COVID-19 National Resilience Cohort, the overarching aim of this thesis was to better understand the role of psychosocial factors in COVID-19 severity and to explore the long-term effects of the pandemic on population mental health and health service use. In Study I, we explored the link between childhood maltreatment and COVID-19 hospitalizations and deaths, examining potential mechanisms and the role of disease susceptibility. In Study II, we analysed trends in new diagnoses of anxiety and depression, as well as new prescriptions for anxiolytics and antidepressants in the UK from March 2020 to August 2021. In Study III, we identified different depressive symptom patterns in Iceland during the COVID-19 pandemic and examined their associated factors and long-term effects. In Study IV, we investigated trends in perceived disruptions in health service use in Iceland during the pandemic and how these disruptions relate to sociodemographic factors, preexisting health conditions, and overall well-being. The findings of these studies reveal resilience and vulnerability factors of COVID-19 severity, population mental health and access to health services during the COVID-19 pandemic with considerable implications for research and prevention in future pandemics.