title: Shift work in young adults and carotid artery intima-media thickness: The Cardiovascular Risk in Young Finns study.
abstract: OBJECTIVE
  Shift work is associated with an elevated risk of cardiovascular disease, but the timing or mechanisms of this association is unclear.
  
  
  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.
authors.affiliation: Finnish Institute of Occupational Health, Helsinki, Finland. Sampsa.Puttonen@ttl.fi
authors.forename: Sampsa
authors.initials: S
authors.lastname: Puttonen
authors.forename: Mika
authors.initials: M
authors.lastname: Kivimäki
authors.forename: Marko
authors.initials: M
authors.lastname: Elovainio
authors.forename: Laura
authors.initials: L
authors.lastname: Pulkki-Råback
authors.forename: Mirka
authors.initials: M
authors.lastname: Hintsanen
authors.forename: Jussi
authors.initials: J
authors.lastname: Vahtera
authors.forename: Risto
authors.initials: R
authors.lastname: Telama
authors.forename: Markus
authors.initials: M
authors.lastname: Juonala
authors.forename: Jorma S A
authors.initials: JS
authors.lastname: Viikari
authors.forename: Olli T
authors.initials: OT
authors.lastname: Raitakari
authors.forename: Liisa
authors.initials: L
authors.lastname: Keltikangas-Järvinen
mesh_terms: D000328:Adult; D050197:Atherosclerosis / Q000175:diagnosis / Q000473:pathology; D002097:C-Reactive Protein / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000175:diagnosis* / Q000208:ethnology / Q000473:pathology; D002339:Carotid Arteries / Q000473:pathology*; D005260:Female; D005387:Finland; D006801:Humans; D008055:Lipids / Q000097:blood; D008297:Male; D012306:Risk; D012923:Social Class; D017539:Tunica Intima / Q000473:pathology*; D017540:Tunica Media / Q000473:pathology*; D014940:Work Schedule Tolerance
chemical_list: D008055:Lipids; D002097:C-Reactive Protein