Evidence map›Paper›PMID 26194183›Full record

ArticleMolecular psychiatry2016

Elevated peripheral cytokines characterize a subgroup of people with schizophrenia displaying poor verbal fluency and reduced Broca's area volume.

S G Fillman, T W Weickert, R K Lenroot, S V Catts, J M Bruggemann, V S Catts, C S Weickert

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PubMed Full text at PMC Publisher
In one paragraph

Article in Molecular psychiatry, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 137 papers, 8 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
137citing papers in PubMed, 8 pooled it
6.8field-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

137 citing papers in PubMed, 8 syntheses or guidelines pooled it, 271 citations in OpenAlex.

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77 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

7 authors at 2 institutions in 1 country.

S G FillmanSchizophrenia Research Institute, Darlinghurst, New South Wales, Australia.
T W WeickertSchizophrenia Research Institute, Darlinghurst, New South Wales, Australia.
R K LenrootSchizophrenia Research Institute, Darlinghurst, New South Wales, Australia.
S V CattsSchizophrenia Research Laboratory, Neuroscience Research Australia, Sydney, New South Wales, Australia.
J M BruggemannSchizophrenia Research Laboratory, Neuroscience Research Australia, Sydney, New South Wales, Australia.
V S CattsSchizophrenia Research Institute, Darlinghurst, New South Wales, Australia.
C S WeickertSchizophrenia Research Institute, Darlinghurst, New South Wales, Australia.
Neuroscience Research Australia · AUSchizophrenia Research Institute · AU

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Previous studies on schizophrenia have detected elevated cytokines in both brain and blood, suggesting neuroinflammation may contribute to the pathophysiology in some cases. We aimed to determine the extent to which elevated peripheral cytokine messenger RNA (mRNA) expression: (1) characterizes a subgroup of people with schizophrenia and (2) shows a relationship to cognition, brain volume and/or symptoms. Forty-three outpatients with schizophrenia or schizoaffective disorder and matched healthy controls were assessed for peripheral cytokine mRNAs (interleukin (IL)-1β, IL-2, IL-6, IL-8 and IL-18), intelligence quotient, memory and verbal fluency, symptom severity and cortical brain volumes integral to language (that is, Broca's and Wernicke's areas). IL-1β mRNA levels were 28% increased in schizophrenia compared with controls (t(82)=2.64, P<0.01). Using a two-step clustering procedure, we identified a subgroup of people displaying relatively elevated cytokine mRNA levels (17/43 people with schizophrenia and 9/42 controls). Individuals with schizophrenia in the elevated cytokine subgroup performed significantly worse than the low-cytokine subgroup on verbal fluency (F(1,40)=15.7, P<0.001). There was a 17% volume reduction of the left pars opercularis (POp) (Broca's area) in patients with elevated cytokines compared with patients with lower cytokines (F(1,29)=9.41, P=0.005). Negative linear relationships between IL-1β mRNA levels and both verbal fluency and left POp volume were found in schizophrenia. This study is among the first to link blood biomarkers of inflammation with both cognitive deficits and brain volume reductions in people with schizophrenia, supporting that those with elevated cytokines represent a neurobiologically meaningful subgroup. These findings raise the possibility that targeted anti-inflammatory treatments may ameliorate cognitive and brain morphological abnormalities in some people with schizophrenia.

Indexed as

AdultBrainBrain DiseasesBrain MappingBroca AreaCytokinesFemaleHumansImage Processing, Computer-AssistedIntelligence TestsLanguageMagnetic Resonance ImagingMaleMiddle AgedPsychiatric Status Rating ScalesPsychotic DisordersCytokines

Identifiers

PMID26194183
PMCPMC4960447
OpenAlexW1608349302

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-ND
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.