Doctoral Defense in Epidemiology

On Monday, April 7, 2025, Yue Wang will defend her doctoral dissertation in epidemiology at the Faculty of Medicine, University of Iceland. The dissertation is titled: The COVID-19 pandemic: early life adversities, mental health trajectories, and health service use.

Opponents are Dr. Matthias Pierce, expert in epidemiology and biostatistics at the University of Manchester, and Dr. Rikke Thaarup Wesselhøft, associate professor at the University of Southern Denmark.

The supervisor was Professor Unnur Anna Valdimarsdóttir, and the co-supervisor was Professor Thor Aspelund. In addition, the doctoral committee included Professor Arna Hauksdóttir, Professor Helga Zoega, and Professor Huan Song.

Professor Þórarinn Guðjónsson, Dean of the Faculty of Medicine, will chair the ceremony, which will take place in Hátíðarsalur in the Main building of University of Iceland at 1:00 PM.

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.

About the Doctoral Candidate
Yue Wang was born in China in 1995. She obtained a B.Sc. degree in public health from Sichuan University in 2018 and a master's degree in psychology and mental health from the same university in 2021. Yue began her doctoral studies at the University of Iceland in 2022.