Evidence map›Paper›PMID 41407484›Full record

SynthesisBMJ mental health2025

Brain fog with long covid and chemotherapy: systematic review and meta-analysis.

Jack Christopher Wilson, Kathy Y Liu, Emma Mittelman, Polen Bareke, Eli Shleifer, Robert Howard

Abstract readSystematic ReviewMeta-Analysis
In one paragraph

Synthesis in BMJ mental health, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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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

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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

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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

6 authors.

Jack Christopher WilsonPsychiatry, UCL, London, UK jack.wilson.13@ucl.ac.uk.ORCID 0000-0001-6869-1010
Kathy Y LiuPsychiatry, UCL, London, UK.ORCID 0000-0002-7482-2758
Emma MittelmanNorth London NHS Foundation Trust, London, UK.
Polen BarekeUCL Medical School, London, UK.
Eli ShleiferUCL Medical School, London, UK.
Robert HowardPsychiatry, UCL, London, UK.

Funding

MRC UK Medical Research Council MR/S021418/1
6 · The paper itself

Abstract

questionWhat are the cognitive, functional and affective characteristics of brain fog in individuals with long covid and following chemotherapy, and how are these features assessed across studies? STUDY SELECTION AND ANALYSIS: In March 2024, we conducted a systematic review and meta-analysis of peer-reviewed studies assessing cognition, function or mood in adults (≥18 years) with brain fog after COVID-19 or chemotherapy. PubMed, Embase and Web of Science were searched systematically according to eligibility criteria to March 2024, with an update in May 2025. Random-effects meta-analyses using the 'dmetar' package (V.0.0.9000) in R V.4.3.1 were performed for studies comparing individuals with and without brain fog. Bias was assessed using the National Institutes of Health Study Quality Assessment Tools.

findingsOf 3077 records screened, 65 studies met inclusion criteria: 40 investigated brain fog in long covid and 25 in chemotherapy populations. Considerable variation in assessment tools was observed. Montreal Cognitive Assessment was the most common cognitive test in long covid studies; Functional Assessment of Cancer Therapy-Cognitive Function was most used in chemotherapy studies. Nine long covid studies were eligible for meta-analysis. Compared with controls, individuals with brain fog had significantly lower cognitive performance (Hedge's g=-0.63, 95% CI -1.15 to -0.12), higher fatigue (Hedge's g=2.64, 95% CI 0.41 to 4.86) and more depressive symptoms (Hedge's g=1.48, 95% CI 0.40 to 2.55). Heterogeneity was high (I

conclusionsBrain fog in long covid and chemotherapy populations is associated with cognitive complaints, fatigue and mood disturbance, though assessment methods differ widely. To improve comparability and clinical understanding, we propose adoption of consistent tools and definitions in future studies. This will be a crucial step in generating findings that can be meaningfully compared across populations. PROSPERO REGISTRATION NUMBER: CRD42024520549.

Indexed as

Antineoplastic AgentsCognitive DysfunctionCOVID-19NeoplasmsHumansSARS-CoV-2Antineoplastic AgentsCognition DisordersMood DisordersNeurocognitive Disorders

Identifiers

PMID41407484
PMCPMC12716526

What Socratic holds

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LicenceCC BY
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Registered trials

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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 Socratic graph.