Evidence map›Paper›PMID 41643642›Full record

ArticleJournal of preventive medicine and public health = Yebang Uihakhoe chi2026

Long Working Hours and Risk of Ischemic Heart Disease Among Japanese Workers: The Jichi Medical School Cohort Study.

Mayumi Saiki, Akizumi Tsutsumi, Jian Li

Abstract read
In one paragraph

Article in Journal of preventive medicine and public health = Yebang Uihakhoe chi, 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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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

3 authors.

Mayumi SaikiJoe C. Wen School of Nursing, University of California Los Angeles, Los Angeles, CA, USA.
Akizumi TsutsumiDepartment of Public Health, Kitasato University School of Medicine, Sagamihara, Japan.
Jian LiJoe C. Wen School of Nursing, University of California Los Angeles, Los Angeles, CA, USA.

Funding

Foundation for the Development of the Community, Tochigi, JapanNIOSH CDC HHS R21OH012446NIOSH CDC HHS T42 OH008412Southern California Education and Research CenterUS Centers for Disease Control and Prevention R21OH012446
6 · The paper itself

Abstract

objectivesKaroshi, or "death from overwork," has been recognized for decades; however, epidemiological findings regarding long working hours (LWH) and ischemic heart disease (IHD) remain inconsistent. This study aimed to provide new evidence on the association between LWH and IHD, while accounting for job strain among Japanese workers, both male and female.

methodsThis study utilized data from 6670 workers participating in the Jichi Medical School Cohort Study. Baseline working hours were categorized as <5.0, 5.0 to 6.9, 7.0 to 8.9 (reference), 9.0 to 10.9, and ≥11.0 hr/day. Fatal and non-fatal incident IHD cases were determined during follow-up using International Classification of Diseases, 10th revision codes. Multivariable Cox proportional hazards models were used to examine associations, adjusting for socio-demographic factors, lifestyle behaviors, cardiometabolic characteristics, and job strain.

resultsDuring a mean follow-up of 12 years, 58 incident IHD cases (42 male and 16 female) were documented. Long working hours (≥11.0 hr/day) were significantly associated with an increased risk of IHD in the total sample (hazard ratio, 2.92; 95% confidence interval, 1.15 to 7.39), and the overall pattern of associations was similar in sex-stratified analyses.

conclusionsThese findings suggest that LWH independently increases the risk of IHD among Japanese workers, even after adjustment for job strain, underscoring the importance of managing working hours to reduce karoshi in both male and female workers.

Indexed as

Myocardial IschemiaAdultCohort StudiesEast Asian PeopleFemaleHumansJapanMaleMiddle AgedProportional Hazards ModelsRisk FactorsSchools, MedicalWorking ConditionsWork Schedule ToleranceCohort studiesJapanLong working hoursMyocardial ischemia

Identifiers

PMID41643642
PMCPMC13084223

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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 OpenQuestion graph.