Evidence map›Paper›PMID 41936690›Full record

SynthesisSleep & breathing = Schlaf & Atmung2026

Reduced cerebral blood flow in obstructive sleep apnea: A meta-analysis of SPECT and MRI studies.

Annette Rizk, Fernando Caravaggio

Abstract readMeta-AnalysisReview
PubMed Publisher
In one paragraph

Synthesis in Sleep & breathing = Schlaf & Atmung, 2026. 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
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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

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5 · Who and what money

Authors and funding

2 authors.

Annette RizkDe La Salle College, Institute of the Brothers of the Christian Schools, 131 Farnham Avenue, Toronto, ON, M4V 1H7, Canada.
Fernando CaravaggioDe La Salle College, Institute of the Brothers of the Christian Schools, 131 Farnham Avenue, Toronto, ON, M4V 1H7, Canada. fernando.caravaggio@gmail.com.ORCID http://orcid.org/0000-0002-9048-4963

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeObstructive sleep apnea (OSA) is associated with increased risk of neurovascular and neurodegenerative disorders. However, cerebral blood flow (CBF) abnormalities in OSA remains unclear due to mixed findings across studies.

methodWe conducted a meta-analysis and activation likelihood estimation (ALE) analyses of neuroimaging data to clarify the nature and extent of CBF changes in patients with OSA.

resultsAmong MRI studies employing arterial spin labelling (ASL) (k = 6), whole-brain CBF was significantly reduced in OSA patients compared to controls (SMD=-0.36, Z=-3.22, p=.001; CI: − 0.58 to − 0.14). Notably, this effect was not observed in non-ASL MRI studies (k = 4) (SMD=0.06, Z=0.27, p=.79; CI: − 0.35 to 0.46). ALE analyses revealed consistent hypoperfusion in the left parietal lobe across SPECT studies and in the left caudate, bilateral anterior cingulate cortex, and right medial frontal gyrus across MRI studies.

conclusionOur findings suggest that whole-brain CBF is modestly reduced in OSA, particularly when measured using ASL MRI. Regional hypoperfusion is consistently observed in fronto-striatal and parietal regions, though convergence is modality-specific. Variability in imaging techniques may account for discrepancies in the literature. Large-scale studies (n ≥ 140 per group) are warranted to investigate the potential cause(s) of CBF abnormalities in OSA.

Indexed as

BrainCerebrovascular CirculationMagnetic Resonance ImagingSleep Apnea, ObstructiveTomography, Emission-Computed, Single-PhotonHumansArterial spin labellingASLCerebral blood flow,Obstructive sleep apneaSPECT

Identifiers

PMID41936690

What Socratic holds

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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.