Evidence map›Paper›PMID 42875771›Full record

SynthesisBMC medicine2026

Longitudinal associations between loneliness and outcomes of Common Mental Disorders (CMDs): A systematic review and meta-analysis.

Theodora Stefanidou, Siying Li, Kinga Lagan, Gamze Evlat, Hannah Gray, Jasmine Harju-Seppänen, Amber Jarvis, Millie O'Sullivan, Shivangi Talwar, Gemma Lewis and 4 more

Abstract readSystematic ReviewMeta-Analysis
In one paragraph

Synthesis in BMC medicine, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

14 authors.

Theodora StefanidouDivision of Psychiatry, University College London (UCL), London, UK. theodora.stefanidou.15@ucl.ac.uk.
Siying LiCentre for Outcomes Research and Effectiveness (CORE), Research Department of Clinical, Educational & Health Psychology, University College London (UCL), London, UK.ORCID http://orcid.org/0000-0002-2689-6648
Kinga LaganDivision of Psychiatry, University College London (UCL), London, UK.
Gamze EvlatNorth London NHS Foundation Trust, London, UK.ORCID http://orcid.org/0009-0000-5144-5542
Hannah GrayDivision of Psychiatry, University College London (UCL), London, UK.
Jasmine Harju-SeppänenInstitute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.
Amber JarvisDivision of Psychiatry, University College London (UCL), London, UK.
Millie O'SullivanDivision of Psychiatry, University College London (UCL), London, UK.
Shivangi TalwarDivision of Psychiatry, University College London (UCL), London, UK.ORCID http://orcid.org/0000-0001-9025-2823
Gemma LewisDivision of Psychiatry, University College London (UCL), London, UK.
Joshua E J BuckmanCentre for Outcomes Research and Effectiveness (CORE), Research Department of Clinical, Educational & Health Psychology, University College London (UCL), London, UK.
Alexandra PitmanDivision of Psychiatry, University College London (UCL), London, UK.ORCID http://orcid.org/0000-0002-9742-1359
Sonia JohnsonDivision of Psychiatry, University College London (UCL), London, UK.ORCID http://orcid.org/0000-0002-2219-1384
Brynmor Lloyd-EvansDivision of Psychiatry, University College London (UCL), London, UK.ORCID http://orcid.org/0000-0001-9866-788X

Funding

Economic and Social Research Council PhD
6 · The paper itself

Abstract

backgroundLoneliness has been increasingly associated with poor mental health outcomes, yet its prognostic role in people with Common Mental Disorders (CMDs) remains unclear. This systematic review aimed to examine whether loneliness is longitudinally associated with mental health outcomes in individuals with CMDs, regardless of treatment status.

methodsWe searched PsycINFO, MEDLINE, Embase and CINAHL from inception to October 2025 for longitudinal studies examining associations between baseline loneliness and CMD outcomes at follow-up. Eligible studies included adults aged 16+ with CMDs. We conducted a narrative synthesis and where appropriate, random-effects meta-analyses for binary depression outcomes reflecting unfavourable course (recurrence, persistence, or non-remission). Study quality was assessed using the Newcastle-Ottawa Scale, and certainty of evidence was evaluated using GRADE. The protocol was registered with PROSPERO (registration number: CRD42023410401).

resultsWe included 22 studies, of which the majority focused on depression-related outcomes (operationalised as symptom severity, recurrence, persistence, remission, and service utilisation). Our narrative synthesis showed consistent associations between higher baseline loneliness and poorer depression-related outcomes at follow-up in people with CMDs across clinical, community, and treatment settings. Meta-analysis of four studies (all in older adults with depression) showed that individuals reporting loneliness at baseline had over three times the odds of poor depression outcomes at follow-up compared with those not lonely (pooled adjusted OR 3.26, 95% CI [2.26-4.70], p < 0.001). This finding should be interpreted with caution, as only one of the four studies adjusted for baseline depressive symptom severity. The few studies capturing suicidal ideation, anxiety, and mixed CMD outcomes found limited and inconsistent evidence. The GRADE certainty of evidence was high for depression outcomes, low for suicidal ideation and anxiety outcomes, and very low for mixed CMD outcomes.

conclusionsLoneliness is consistently associated with poorer subsequent depression outcomes in people with CMDs, particularly depressive disorders. These findings suggest loneliness may represent an important prognostic factor in depression and warrant further evaluation in intervention studies. Further high-quality longitudinal research is needed to clarify whether-and under what conditions-loneliness affects outcomes for other CMDs and treatment effectiveness.

Indexed as

LonelinessMental DisordersDepressionHumansLongitudinal StudiesAnxietyCommon mental disordersDepressionLonelinessLongitudinalMental healthMeta-analysisSystematic review

Identifiers

PMID42875771
PMCPMC13670620

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.