title: Shiftwork and decline in endothelial function among police officers.
abstract: Our objective was to assess the influence of shiftwork on change in endothelial function.
  
  
  
  This longitudinal study was conducted in 188 police officers (78.2% men). Shiftwork status (day, afternoon, night) was assessed objectively using daily Buffalo, NY payroll work history records. Brachial artery flow-mediated dilation (FMD) was assessed using ultrasound. Mean change in FMD% between 2004-2009 and 2010-2015 was compared across shiftwork using analysis of variance/covariance.
  
  
  
  Overall, mean FMD% decreased from 5.74 ± 2.83 to 3.88 ± 2.11 over an average of 7 years among all officers; P < 0.0001. Effect modification by gender was significant. Among men (but not women), those who worked day shifts had a smaller mean (±SE) decrease in FMD% (-0.89 ± 0.35) compared with those who worked the afternoon (-2.69 ± 0.39; P = 0.001) or night shifts (-2.31 ± 0.45; P = 0.020) after risk factor adjustment.
  
  
  
  Larger declines in endothelial function were observed among men who worked afternoon or night shifts. Further investigation is warranted. Am. J. Ind. Med. 59:1001-1008, 2016. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.
authors.affiliation: Health Effects Laboratory Division, Biostatistics and Epidemiology Branch, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Morgantown, West Virginia. lcharles@cdc.gov.
authors.forename: Luenda E
authors.initials: LE
authors.lastname: Charles
authors.affiliation: Health Effects Laboratory Division, Biostatistics and Epidemiology Branch, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Morgantown, West Virginia.
authors.forename: Songzhu
authors.initials: S
authors.lastname: Zhao
authors.affiliation: Health Effects Laboratory Division, Biostatistics and Epidemiology Branch, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Morgantown, West Virginia.
authors.forename: Desta
authors.initials: D
authors.lastname: Fekedulegn
authors.affiliation: Department of Epidemiology and Environmental Health, School of Public Health and Health Professions, State University of New York at Buffalo, Buffalo, New York.
authors.forename: John M
authors.initials: JM
authors.lastname: Violanti
authors.affiliation: Health Effects Laboratory Division, Biostatistics and Epidemiology Branch, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Morgantown, West Virginia.
authors.forename: Michael E
authors.initials: ME
authors.lastname: Andrew
authors.affiliation: Health Effects Laboratory Division, Biostatistics and Epidemiology Branch, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Morgantown, West Virginia.
authors.forename: Cecil M
authors.initials: CM
authors.lastname: Burchfiel
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001783:Blood Flow Velocity; D001916:Brachial Artery / Q000000981:diagnostic imaging / Q000503:physiopathology*; D004730:Endothelium, Vascular / Q000503:physiopathology; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D016495:Police; D012039:Regional Blood Flow / Q000502:physiology*; D012737:Sex Factors; D014463:Ultrasonography / Q000379:methods; D014664:Vasodilation / Q000502:physiology*; D014940:Work Schedule Tolerance / Q000502:physiology*
keywords: brachial artery reactivity; endothelial function; flow-mediated dilation; law enforcement officers; police officers; shiftwork