Understanding the interplay between social isolation, age, and loneliness during the COVID-19 pandemic.

Previous studies indicate differences in experiences of loneliness during the COVID-19 pandemic but are constricted by limited timeframes and absence of key risk factors. This study explores temporal and inter-individual variations of loneliness in Canadians over the pandemic's first year (April 2020-2021), by identifying loneliness trajectories. It then seeks to provide information about groups overrepresented in high and persistent loneliness trajectories by examining their associations with risk factors: social isolation indicators (living alone, adherence to health measures limiting in-person contacts, and online contacts), young adultood, and the interactions between these factors. Data comes from a large longitudinal study with a representative Canadian sample (n = 1763) and 11 measurement times. Analyses consist of (1) a group-based modelling approach to identify trajectories of loneliness and (2) multinomial logistic regressions to test associations between risk factors and trajectory membership. Varied experiences of loneliness during the pandemic were revealed as five trajectories were identified: moderate-unstable (38.5%), high-stable (26.7%), low-unstable (20.5%), very low-stable (8.6%), and very high-decreasing (5.7%). Individuals living alone associated with higher trajectories. Contrary to our expectations, adhering to social distancing measures and having fewer online contacts associated with lower trajectories. Age and interactions were not significant in regard to loneliness trajectories.