Evidence map›Paper›PMID 31326932›Full record

SynthesisBMJ open2019

Systematic review and meta-analysis of the association between peripheral inflammatory cytokines and generalised anxiety disorder.

Harry Costello, Rebecca L Gould, Esha Abrol, Robert Howard

Open access · goldAbstract readMeta-AnalysisSystematic Review
PubMed Full text at PMC Publisher
In one paragraph

Synthesis in BMJ open, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 135 papers, 6 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
135citing papers in PubMed, 6 pooled it
7.0field-weighted citation impact, top 2% of its field
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

135 citing papers in PubMed, 6 syntheses or guidelines pooled it, 240 citations in OpenAlex.

  1. Inflammatory biomarkers and oral microbiome alterations in depression and anxiety disorders: a systematic review.The world journal of biological psychiatry : the official journal of the World Federation of Societies of Biological Psychiatry · 2026
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  10. The impact of anxiety on vulvar dermatological diseases: a systematic review.International journal of women's dermatology · 2026
    Review
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  14. Prenatal depression and psychotropics in offspring asthma and atopic dermatitis.Journal of the Chinese Medical Association : JCMA · 2026
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75 more citing papers are in PubMed but not listed here.

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

4 authors at 1 institution in 1 country.

Harry CostelloDivision of Psychiatry, University College London, London, UK.
Rebecca L GouldDivision of Psychiatry, University College London, London, UK.
Esha AbrolDivision of Psychiatry, University College London, London, UK.
Robert HowardDivision of Psychiatry, University College London, London, UK.
University College London · GB

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectiveInflammation has been implicated in the aetiology of mental illness. We conducted the first systematic review and meta-analysis of the association between peripheral markers of inflammation and generalised anxiety disorder (GAD).

designSystematic review and meta-analysis of studies measuring peripheral cytokine levels in people with GAD compared with controls. DATA SOURCES: MEDLINE (1950-), EMBASE (1947-), PsycINFO (1872-) and Web of Science (1945-) databases up until January 2018. ELIGIBILITY CRITERIA: Primary, quantitative research studies of people with a diagnosis of GAD assessed using a standardised clinical interview that measured peripheral inflammatory markers. DATA EXTRACTION AND SYNTHESIS: Two independent reviewers extracted data and assessed study quality. Meta-analysis using a random-effects model was conducted for individual cytokines where data from three or more studies were available.

results14 of 1718 identified studies met the inclusion criteria, comprising 1188 patients with GAD and 10 623 controls. In total 16 cytokines were evaluated. Significantly raised levels of C reactive protein (CRP), interferon-γ and tumour necrosis factor-α were reported in patients with GAD compared with controls in two or more studies. Ten further proinflammatory cytokines were reported to be significantly raised in GAD in at least one study. However, 5 of 14 studies found no difference in the levels of at least one cytokine. Only CRP studies reported sufficient data for meta-analysis. CRP was significantly higher in people with GAD compared with controls, with a small effect size (Cohen's d=0.38, 0.06-0.69), comparable with that reported in schizophrenia. However, heterogeneity was high (I

conclusionThere is preliminary evidence to suggest an inflammatory response in GAD, but it remains unclear whether inflammatory cytokines play a role in the aetiology. GAD remains a poorly studied area of neuroinflammation compared with other mental disorders, and further longitudinal studies are required.

Indexed as

Anxiety DisordersBiomarkersCytokinesHumansInflammationBiomarkersCytokinesanxiety disordersimmunologypsychiatry

Identifiers

PMID31326932
PMCPMC6661660
OpenAlexW2964215777

What OpenQuestion holds

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LicenceCC BY
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.