Tackling social disconnection: an umbrella review of RCT-based interventions targeting social isolation and loneliness.

Background: Social isolation and loneliness are urgent public health concerns associated with negative physical and mental health outcomes. Understanding effective remedies is crucial in addressing these problems. This umbrella review aimed to synthesize and critically appraise scientific evidence on the effectiveness of social isolation and loneliness interventions overall and across subgroups. We focused on systematic reviews (SRs) of randomized controlled trials (RCTs).

Methods: We searched seven databases (June 2022 and updated June 2023) and supplemented the search with grey literature and reference screening to identify SRs published since 2017. Screening, data extraction, and quality assessment using the AMSTAR2 tool were conducted independently by author pairs, with disagreements resolved through discussion.

Results: We included 29 SRs, 16 with meta-analysis and 13 with narrative synthesis. All SRs focused on loneliness, with 12 additionally examining social isolation. Four SRs focused on young people, 11 on all ages, and 14 on older adults. The most frequently examined intervention types were social (social contact, social support), psychological (therapy, psychoeducation, social skills training), and digital (e.g., computer use and online support). Meta-analyses indicated small-to-moderate beneficial effects, while narrative synthesis demonstrated mixed or no effect. Social interventions for social isolation and psychological interventions for loneliness were the most promising. However, caution is warranted due to the effects' small magnitude, significant heterogeneity, and the variable quality of SRs. Digital and other interventions showed mixed or no effect; however, caution is advised in interpreting these results due to the highly diverse nature of the interventions studied.

Conclusions: This overview of SRs shows small to moderate effectiveness of social interventions in reducing social isolation and psychological ones in tackling loneliness. Further rigorously conducted RCTs and SRs are needed to guide policy decisions regarding the implementation of efficacious and scalable interventions. Evaluation should focus on both preventive structural interventions and tailored mitigating strategies that address specific types and causes of loneliness.