Article Text

other Versions

PDF
Original Article
Shift work and 20-year incidence of acute myocardial infarction: results from the Kuopio Ischemic Heart Disease Risk Factor Study
  1. Aolin Wang1,
  2. Onyebuchi A Arah1,2,3,
  3. Jussi Kauhanen4,
  4. Niklas Krause1,5
  1. 1Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles (UCLA), Los Angeles, California, USA
  2. 2Center for Health Policy Research, UCLA, Los Angeles, California, USA
  3. 3California Center for Population Research, UCLA, Los Angeles, California, USA
  4. 4Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
  5. 5Department of Environmental Health Sciences, The Fielding School of Public Health, UCLA, Los Angeles, California, USA
  1. Correspondence to Dr Niklas Krause, Department of Environmental Health Sciences and Department of Epidemiology, Fielding School of Public Health, UCLA, Box 95–1772; 56-071 CHS, 650 Charles E. Young Drive South, Los Angeles, CA 90095-1772, USA; niklaskrause{at}ucla.edu

Abstract

Objectives It remains unclear whether different types of shift work impose similar risks for cardiovascular events in middle-aged workers, especially those with pre-existing ischaemic heart disease (IHD). This study investigated the relations between different shift types and incident acute myocardial infarction (AMI) among men with and without pre-existing IHD, respectively.

Methods We analysed data on 1891 men, aged 42–60 years at baseline, in the prospective Kuopio Ischemic Heart Disease Risk Factor Study cohort, using Cox proportional hazard models with adjustment for demographic, biological, behavioural and psychosocial job factors. We evaluated the associations of baseline shift work with 20-year incidence of AMI, and their modification by pre-existing IHD, using both stratified analysis and models with product terms between shift work and IHD.

Results Travelling work (at least 3 nights per week away from home) was strongly positively associated with AMI among men with IHD (HR=2.45, 95% CI 1. 08 to 5.59) but not among men without (HR=0.93, 95% CI 0.43 to 2.00). No clear associations were found between other types of shift work and AMI for both men with and without IHD. On both additive and multiplicative scales, baseline IHD status positively modified the association of travelling work with AMI (relative excess risk for interaction=3.23, 95% CI −0.50 to 6.97, p for multiplicative interaction=0.044).

Conclusions We found mixed results for the associations between different types of shift work and AMI among those with and without pre-existing IHD. Future research should investigate these associations and effect modification for a broad spectrum of work schedules.

Statistics from Altmetric.com

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.