title: An industry-based cohort study of the association between weight gain and hypertension risk among rotating shift workers.
abstract: OBJECTIVE
  We investigated whether the association between shift work and hypertension is independent of weight gain.
  
  
  METHODS
  Subjects were 10,173 male employees (9209 daytime workers, 964 three-shift workers; mean follow-up period: 12.7 years). Hypertension was defined as systolic blood pressure 140 mm Hg or more or diastolic blood pressure 90 mm Hg or more. The risk of developing hypertension among shift workers was estimated using a Cox proportional hazards model with adjustment for several factors.
  
  
  RESULTS
  Analysis revealed that "shift work" (hazard ratio [HR]: 1.85; 95% confidence interval [CI]: 1.68, 2.03), "baseline body mass index" (HR: 1.13; 95% CI: 1.12, 1.15), and "increase in body mass index during follow-up" (HR: 1.15; 95% CI: 1.13, 1.17) were significant independent risk factors for hypertension.
  
  
  CONCLUSIONS
  Shift work is a significant risk factor for hypertension that is independent of both starting weight and weight gained over years of work.
authors: Department of Public Health, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan. kubo@med.uoehu.ac.jp
authors: Tatsuhiko
authors: T
authors: Kubo
authors: Yoshihisa
authors: Y
authors: Fujino
authors: Takehiro
authors: T
authors: Nakamura
authors: Masamizu
authors: M
authors: Kunimoto
authors: Hidetoshi
authors: H
authors: Tabata
authors: Takuto
authors: T
authors: Tsuchiya
authors: Koji
authors: K
authors: Kadowaki
authors: Haruka
authors: H
authors: Odoi
authors: Ichiro
authors: I
authors: Oyama
authors: Shinya
authors: S
authors: Matsuda
mesh_terms: D000328:Adult; D001795:Blood Pressure Determination; D015992:Body Mass Index; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000175:diagnosis / Q000209:etiology*; D007221:Industry; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000175:diagnosis; D009784:Occupational Diseases / Q000175:diagnosis / Q000209:etiology*; D016016:Proportional Hazards Models; D012307:Risk Factors; D015430:Weight Gain; D014940:Work Schedule Tolerance / Q000502:physiology*