Background: Although the COVID-19 pandemic has affected depression, evidence of the role of pre-pandemic history of depression remains limited.
Aims: We investigated how long-term trajectories of depressive symptomatology before the COVID-19 pandemic were related to depression during the pandemic, over and above the latest pre-pandemic depression status. Furthermore, we examined whether those experiencing depression closer to the pandemic were at higher risk during the pandemic.
Method: Employing data from waves 4-9 of the English Longitudinal Study of Ageing (2008-2009 to 2018-2019), we used group-based trajectory modelling on 3925 English older adults aged 50+ years to identify distinctive trajectories of elevated depressive symptoms (EDS). Fully adjusted logistic models were then used to examine the associations between trajectories and depression during the COVID-19 pandemic (June-July and November-December 2020).
Results: We identified four classes of pre-pandemic trajectories of EDS. About 5% were classed as 'enduring EDS', 8% as 'increasing EDS', 10% as 'decreasing EDS' and 77% as 'absence of EDS'. Compared with respondents with absence of EDS, those with EDS history were more likely to have depression during the COVID-19 pandemic, particularly those with enduring or increasing EDS in the previous 10 years. Moreover, the frequency of EDS was more crucial in predicting the risks of depression during the pandemic than the timing of the latest episode.
Conclusions: Trajectories of depressive symptomatology are an important risk factor for older adults' mental health, particularly in the context of crisis. Older people with enduring or increasing EDS should receive particular attention from policy makers when provisioning post-pandemic well-being support.
Keywords: Depressive disorders; epidemiology; health economics; history of psychiatry; statistical methodology.