Longitudinal Study Comparing Mental Health Outcomes in Frontline Emergency Department Healthcare Workers through the Different Waves of the COVID-19 Pandemic.

As countries transition from the COVID-19 pandemic to endemic status, healthcare systems continue to be under pressure. We aimed to quantify changes in depression, anxiety, stress and post-traumatic stress disorder (PTSD) between 3 cohorts (2020, 2021 and 2022) of our Emergency Department (ED) healthcare workers (HCWs) and those who had worked through all 3 phases of the pandemic; and identify factors associated with poorer mental health outcomes (MHOs). In this longitudinal single-centre study in Singapore, three surveys were carried out yearly (2020, 2021 and 2022) since the COVID-19 outbreak. Depression, anxiety and stress were measured using DASS-21, and PTSD was measured using IES-R. A total of 327 HCWs (90.1%) participated in 2020, 279 (71.5%) in 2021 and 397 (92.8%) in 2022. In 2022, ED HCWs had greater concerns about workload (Mean score ± SD: 2022: 4.81 ± 0.86, vs. 2021: 4.37 ± 0.89, vs. 2020: 4.04 ± 0.97) and perceived to have less workplace support (2022: 4.48 ± 0.76, vs. 2021: 4.66 ± 0.70, vs. 2020: 4.80 ± 0.69). There was overall worsening depression (27.5% in 2020, 29.7% in 2021 and 32.2% in 2022) and stress (12.2% in 2020, 14.0% in 2021 and 17.4% in 2022). Healthcare assistants as a subgroup had improving MHOs. ED HCWs who were female and had psychiatric history, were living with the elderly, and had concerns about their working environment, workload and infection had poorer MHOs. This study will guide us in refining existing and devising more focused interventions to further support our ED HCWs' wellbeing.