Risk Factors and Changes in Depression and Anxiety over Time in New Zealand during COVID-19: A Longitudinal Cohort Study

Abstract

This longitudinal study investigated changes in and risk factors for anxiety and depression during the COVID-19 pandemic in a New Zealand cohort. Online surveys were distributed to 681 participants at three time-points: May 2020 (Time 1), August–September 2020 (Time 2), and March–April 2021 (Time 3). Participants completed measures of anxiety and depression, alongside measures of possible risk/protective factors. A total of 261 participants completed all three surveys and were included in analyses. Depression and anxiety reduced over time; however, levels were still significantly higher than pre-pandemic norms. Being younger, having a prior mental health disorder, experiencing negative life events due to COVID-19, and being a pet owner were risk factors for poorer depression and anxiety, whereas having higher positive mood was protective. This study demonstrates persisting negative effects of the pandemic on anxiety and depression in a context of low transmission and highlights the importance of providing psychological help to those most at risk.