Development of loneliness and social isolation after spousal loss: A systematic review of longitudinal studies on widowhood

Abstract Background Spousal loss is a stressful life event that is associated with loneliness and social isolation, both of which affect mental and physical health. The primary objective of this paper was to synthesize longitudinal studies that investigated loneliness and social isolation in widowhood. Methods A systematic search of the literature was conducted using three electronic databases. 26 longitudinal studies published through June 2024 were included for further analysis. Participant characteristics, study design, and key findings were extracted. Results Most studies were from the United States or Europe, included more widows than widowers, and assessed loneliness in older adults aged >60 years. Loneliness peaked directly following spousal death, but findings were inconsistent regarding the lasting effects of widowhood. Heterogeneity in the longitudinal trajectories of loneliness was noted, with studies showing linear increases, decreases, or curvilinear relationships over time. Several factors modified the relationship between widowhood and loneliness, including volunteerism, military experience, income, and age. Widowers consistently reported greater loneliness and worse social isolation when compared with widows. Few studies investigated social isolation specifically, but those that did found that social isolation may decrease in widowhood. Conclusions As the world grapples with a social pandemic of loneliness and social isolation, widowed adults may be uniquely affected. Few studies investigated the longitudinal trajectory of loneliness and especially social isolation in widowhood, and those that did found heterogenous results. Future work is needed to understand why some widowed adults are uniquely affected by feelings of loneliness and social isolation while others are not, and whether potentially modifiable factors that moderate or mediate this relationship could be leveraged by psychosocial interventions.