Psychological Well-Being in Adults Across the COVID-19 Pandemic: A Two-Year Longitudinal Study.

Objectives: The COVID-19 pandemic significantly affected global psychological well-being. We explored long-term trajectories of adults' well-being from before the pandemic through its progression and identified risk factors for compromised well-being. Methods: Psychological well-being of a diverse group of 481 adults (18-74 years) was assessed prior to (T0) and during the pandemic (T1-T5: 04-05/2020, 10-11/2020, 04-05/2021, 10-11/2021, 04-05/2022). Latent variable mixture modelling identified subgroups with distinct trajectories of well-being. Ordinal regression analysis investigated risk factors for low well-being during the pandemic. Results: Three subgroups with different trajectories were identified: 73% reported consistently good well-being; 21% experienced decreasing well-being; and 5% exhibited consistently low well-being. Decreasing or consistently low well-being was significantly associated with younger age, limited social support, caregiving responsibilities, concerns about COVID-19 infection, and stress due to pandemic-related changes. Conclusion: While many individuals remained resilient, a vulnerable subgroup experienced mental health challenges over 2 years of the pandemic. Given the global scale, even a small affected proportion represents millions of people. Public health measures are essential to identify and support those at highest risk for impaired psychological well-being.