Evidence mapPaperPMID 42379713Full record

Observational studyBMJ open2026

Differential impact of smoking on intracerebral haemorrhage based on cerebral microbleed status: a case-control study.

Takehito Kuroda, Tomotaka Tanaka, Satoshi Saito, Sonu Bhaskar, Hiroyuki Ishiyama, Ryoma Inui, Yuma Shiomi, Yuriko Nakaoku, Soshiro Ogata, Yoshiaki Morita and 7 more

Registry-linked trialAbstract readObservational Study
In one paragraph

Observational study in BMJ open, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT02251665 (National Cerebral and Cardiovascular Center), which is not on this 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.

NCT02251665 active not recruitingnot on this map

National Cerebral and Cardiovascular Center (NCVC) Stroke Registry

TypeobservationalSponsorNational Cerebral and Cardiovascular Center, JapanRan2016 to 2028Enrolled5,374ConditionsStroke, AcuteArmsNo intervention
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

17 authors.

Takehito KurodaNeurology, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.ORCID http://orcid.org/0000-0002-3711-9983
Tomotaka TanakaNeurology, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan tanakat@ncvc.go.jp.ORCID http://orcid.org/0000-0002-6023-236X
Satoshi SaitoNeurology, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.ORCID http://orcid.org/0000-0001-8608-058X
Sonu BhaskarNeurology, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.ORCID http://orcid.org/0000-0002-9783-3628
Hiroyuki IshiyamaNeurology, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
Ryoma InuiNeurology, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.ORCID http://orcid.org/0000-0002-5229-9054
Yuma ShiomiNeurology, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.ORCID http://orcid.org/0009-0008-7401-1761
Yuriko NakaokuPreventive Medicine and Epidemiology, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
Soshiro OgataPreventive Medicine and Epidemiology, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
Yoshiaki MoritaRadiology, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
Etsuko OzakiEpidemiology for Community Health and Medicine, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Nagato KuriyamaEpidemiology for Community Health and Medicine, Kyoto Prefectural University of Medicine, Kyoto, Japan.ORCID http://orcid.org/0000-0002-6859-535X
Kunihiro NishimuraPreventive Medicine and Epidemiology, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
Masatoshi KogaCerebrovascular Medicine, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
Jin NakaharaNeurology, Keio University School of Medicine, Shinjuku, Tokyo, Japan.
Kazunori ToyodaCerebrovascular Medicine, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
Masafumi IharaNeurology, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.ORCID http://orcid.org/0000-0002-7102-4048

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectivesWhile smoking is a well-established risk factor for various cardiovascular diseases, its association with intracerebral haemorrhage (ICH) remains controversial. Cerebral microbleeds (CMBs) are markers of haemorrhage-prone small vessel disease, but ICH can also occur without detectable CMBs. Therefore, we investigated the association between smoking and ICH according to CMB status.

designSingle-centre retrospective case-control study.

settingA tertiary stroke centre in Osaka, Japan (2017-2021).

participants487 patients with ICH as their first stroke (female sex 41.5%) and 322 controls with non-stroke neurological conditions (female sex 47.5%) were included. Patients with missing CMB evaluation or smoking status data were excluded. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was ICH status, analysed according to CMB status, with current smoking as the primary exposure. Secondary analyses evaluated the association between smoking cessation duration and the odds of ICH, using current smoking as the reference.

resultsPatients with ICH (median age, 70.0 years; presence of CMBs, 53.6%) and controls (median age, 71.0 years; presence of CMBs, 13.4%) were analysed. Among individuals without CMBs, current smoking was more frequently observed in patients with ICH than in controls (25.7% vs 14.0%, p<0.001) and was independently associated with ICH following adjustment for potential confounders (adjusted OR (aOR) 1.84, 95% CI 1.02 to 3.31, p=0.042). Long-term smoking cessation (>10 years) was associated with lower odds of ICH than current smoking (aOR 0.31, 95% CI 0.14 to 0.67, p=0.003), whereas short-term cessation (≤10 years) showed no significant difference. Among individuals with CMBs, no significant association was observed between smoking status and ICH.

conclusionsCurrent smoking was associated with higher odds of ICH among individuals without CMBs, whereas long-term cessation was associated with lower odds. These findings suggest that the absence of CMBs should not be interpreted as the absence of modifiable ICH risk, highlighting the clinical relevance of smoking history in this population. TRIAL REGISTRATION NUMBER: NCT02251665.

Indexed as

Cerebral HemorrhageSmokingAgedAged, 80 and overCase-Control StudiesFemaleHumansJapanMaleMiddle AgedRetrospective StudiesRisk FactorsSmoking CessationStrokeCase-Control StudiesIntracerebral HemorrhageStroke

Identifiers

PMID42379713
PMCPMC13330890

What Socratic holds

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LicenceCC BY-NC
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Registered trials

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.