Abstract

Background Loneliness in later life has been widely associated with poor mental and physical health. However, despite many reviews, current evidence does not provide a clear picture of how to tackle loneliness in older adults through interventions. Research examining the contexts and mechanisms for reducing loneliness through interventions is required to identify how, why, and for who interventions work or do not work.

Methods A critical interpretive synthesis, a review method designed to rigorously and reflexively re-examine existing literature, was conducted to re-consider and identify what matters in interventions. This was enacted through a broad search strategy incorporating database searches, contacting experts, reference-chaining, and team discussions, enabling a flexible and iterative review able to generate new theory.

Results 274 papers were included in the analysis. We identified four dimensions to whether and how interventions worked. Intended outcome mirrored different theoretical perspectives on how to reduce loneliness. Four intended outcomes were identified: cognitive change; improved social connections; physiological change; and a more meaningful life. The second dimension was the level of an intervention - whether it intended to intervene at a micro, meso, or macro level. Thirdly, 13 positive features of interventions were noted to have been evidenced to lead to or constitute more effective interventions. These were interventions that are organised, adaptable, have good staff/volunteers, provide support to attend, routinised, built on shared interests/identities, personalised, culturally aware, co-produced, involve active participation, strengths-based, lasting, and targeted at the appropriate people. Lastly, nine emotions that represent less loneliness were identified: a feeling of reciprocated interactions; emotional and social support; belonging; perspective; self-efficacy; mattering; pride; purpose; and empowerment.

Conclusions Interventions and evaluations should look beyond comparing activities to see which are best and recognise that multidimensionality and variation is vital for individuals and communities with different needs. Identifying what the intended outcome of an intervention is, what level of society it intends to impact, and whether it actions the positive features identified in this study, can be employed to better target the variety of emotions that represent less loneliness.

Competing Interest Statement

The authors have declared no competing interest.

Clinical Protocols

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=572289

Funding Statement

This study was funded by UK Engineering and Physical Sciences Research Council and the National Institute of Health and Care Research: grant codes EP/W031434/1 and EP/W031442/1

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Data Availability

All data produced in the present work are contained in the manuscript

AbbreviationsCISCritical Interpretative SynthesisPRISMAPreferred Reporting Items for Systematic reviews and Meta-Analyses