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Rodent Working Heart Model for the Study of Myocardial Performance and Oxygen Consumption
Published on: August 16, 2016
Shift work, confounding and death from ischaemic heart disease.
1Department of Biostatistics & Epidemiology, School of Public Health, Isfahan University of Medical Sciences, Hezar-Jerib Road, Isfahan, Iran. g_yadegarfar@yahoo.co.uk
Occupational and Environmental Medicine
|May 5, 2007
Summary
Shift work was not associated with an increased risk of death from ischaemic heart disease (IHD). Social class did not confound this relationship in this industrial cohort study.
Area of Science:
- Occupational Health
- Epidemiology
- Cardiovascular Disease Research
Background:
- Shift work is prevalent in many industries, raising concerns about its potential impact on cardiovascular health.
- Ischaemic heart disease (IHD) remains a leading cause of mortality worldwide.
- Understanding occupational exposures and their relation to chronic diseases is crucial for public health.
Purpose of the Study:
- To examine the association between shift work and mortality from ischaemic heart disease (IHD).
- To investigate potential confounding factors, specifically social class and healthy worker effects, in this relationship.
Main Methods:
- A case-referent study was nested within an industrial cohort.
- Cases were deaths from IHD (ICD 410-414) in cohort members aged 75 or under (n=635).
- Matched referents, historical personnel records, and medical data were used to assess shift work, social class, and pre-employment risk factors, with conditional logistic regression employed for analysis.
Main Results:
- 55% of the cohort engaged in shift work, with shift workers more likely to be of lower social class (IV or V).
- The adjusted odds ratio (OR) for IHD mortality among shift workers compared to day workers was 1.11 (90% CI 0.90 to 1.37), reducing to 1.04 (90% CI 0.83 to 1.30) after including social class.
- No significant excess risk of IHD mortality was found for shift workers, and no dose-response relationship was observed.
Conclusions:
- This study found no evidence that shift work increases the risk of death from ischaemic heart disease.
- The findings suggest that social class may confound the relationship between shift work and IHD in more diverse populations.
- Further research is needed to explore these associations in heterogeneous populations.
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