A critical period for pandemic adaptation: The evolution of depressive symptomatology in a representative sample of adults across a 17-month period during COVID-19.

This 17-month longitudinal study on a representative sample of 4,361 Norwegian adults employs an observational ABAB design across 6 repeated assessments and 3 pandemic waves to systematically investigate the evolution of depressive symptomatology across all modifications of social distancing protocols (SDPs) from their onset to termination. Using Latent Change Score Models to analyze 26,166 observations, the study empirically corroborates that critical fluctuations in depressive symptomatology within and across individuals occur during the first 3 months of the pandemic, after which symptom profiles are predominantly consolidated throughout the pandemic period. Contrary to established belief, female sex, young age, lower education and preexisting psychiatric diagnosis only served as adequate predictors of the initial shocks to symptomatology observed during the onset of the pandemic and did not adequately predict subsequent change observed in symptoms within and across individuals. Population-level analyses demonstrated that symptom levels strongly covaried with the presence and strictness of SDPs and were unrelated to COVID-19 incidence rates. Upon predominant termination of SDPs, population-level symptoms began declining, while large heterogeneity was present across the adult population. Detrimental long-term adversities were revealed by 10% of the adults. These individuals displayed chaotic adaptation to the pandemic and its SDPs, exhibiting substantial increases in clinical levels of symptomatology ensuing partial reopening of society and through the remainder of the pandemic, with these deleterious symptoms projected to remain heightened ahead. Frequency of quarantine exposure was incrementally tied with increases in contemporaneously experienced and long-term depressive adversities, with information obtainment through unmonitored sources further associated with contemporaneous and long-term states of heightened symptomatology. (PsycInfo Database Record (c) 2022 APA, all rights reserved).