Shift work in young adults and carotid artery intima-media thickness: The Cardiovascular Risk in Young Finns study

Atherosclerosis. 2009 Aug;205(2):608-13. doi: 10.1016/j.atherosclerosis.2009.01.016. Epub 2009 Jan 21.


Objective: Shift work is associated with an elevated risk of cardiovascular disease, but the timing or mechanisms of this association is unclear.

Methods and results: We examined the relationship between shift work and subclinical atherosclerosis in 1543 (712 men and 831 women, 24-39 years old) young adults as part of the ongoing population-based Cardiovascular Risk in Young Finns study. Carotid atherosclerosis was assessed by measuring the thickness of the common carotid artery intima-media (IMT) complex with ultrasound and carotid plaque. Working schedules were categorized as day work or shift work (2- or 3-shift work, regular evening or night work). In men, shift work was associated with higher mean IMT (B=0.029, p=0.021), maximum IMT (B=0.029, p=0.028), and a 2.2-fold odds of carotid plaque (95% CI, 1.2-4.0). These relationships persisted after adjustment for age and risk factors, such as low socio-economic position, job strain, smoking, diet, family history of CHD, physical inactivity, alcohol consumption, obesity, homocysteine, C-reactive protein, blood pressure, and lipids. In women, no association was found between shift work and carotid atherosclerosis indicators.

Conclusions: Our results suggest that shift work accelerates the atherosclerotic process and that the effects of shift work on subclinical atherosclerosis are observable in men already before age 40.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Atherosclerosis / diagnosis
  • Atherosclerosis / pathology
  • C-Reactive Protein / metabolism
  • Cardiovascular Diseases / diagnosis*
  • Cardiovascular Diseases / ethnology
  • Cardiovascular Diseases / pathology
  • Carotid Arteries / pathology*
  • Female
  • Finland
  • Humans
  • Lipids / blood
  • Male
  • Risk
  • Social Class
  • Tunica Intima / pathology*
  • Tunica Media / pathology*
  • Work Schedule Tolerance*


  • Lipids
  • C-Reactive Protein