title: Shift work parameters and disruption of diurnal cortisol production in female hospital employees.
abstract: Shift work is associated with an increased risk of cardiovascular diseases (CVD). Disruption of cortisol production is a potential underlying mechanism. This study explored the associations of diurnal quantity and pattern of cortisol production in relation to (1) current shift work status (exclusive day versus rotating days and nights), (2) years of past shift work and (3) parameters of rotating shift work (timing, length and intensity). Female hospital employees (160 day workers and 168 rotating shift workers) from southeastern Ontario, Canada, participated in a cross-sectional study. Participants completed a baseline questionnaire and measures of body height, weight, and waist circumference were taken. Midstream urine samples were collected over two separate 24-hour periods to measure creatinine-adjusted cortisol. Total diurnal cortisol production and pattern were described with two measures of the area under the curve. The effect of shift work on cortisol was modeled using multivariable linear regression analyses. Cortisol production in day workers and shift workers on their day shift were similar; however, shift workers on the night shift had flatter diurnal cortisol curves and produced less cortisol. This suggests that night work is associated with an acute attenuation of cortisol production.
authors.affiliation: a Department of Public Health Sciences , Queen's University , Kingston , Ontario , Canada.
authors.forename: Eleanor Wai Man
authors.initials: EW
authors.lastname: Hung
authors.affiliation: a Department of Public Health Sciences , Queen's University , Kingston , Ontario , Canada.|b Division of Cancer Care and Epidemiology , Cancer Research Institute, Queen's University , Kingston , Ontario , Canada.
authors.forename: Kristan J
authors.initials: KJ
authors.lastname: Aronson
authors.affiliation: a Department of Public Health Sciences , Queen's University , Kingston , Ontario , Canada.|c Research Institute and Centre for Global Child Health, Peter Gilgan Centre for Research and Learning , The Hospital for Sick Children , Toronto , Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Leung
authors.affiliation: a Department of Public Health Sciences , Queen's University , Kingston , Ontario , Canada.|d Kingston General Hospital , Kingston , Ontario , Canada.
authors.forename: Andrew
authors.initials: A
authors.lastname: Day
authors.affiliation: a Department of Public Health Sciences , Queen's University , Kingston , Ontario , Canada.|e School of Nursing , Queen's University , Kingston , Ontario , Canada.
authors.forename: Joan
authors.initials: J
authors.lastname: Tranmer
mesh_terms: D000328:Adult; D015415:Biomarkers; D002940:Circadian Rhythm / Q000502:physiology*; D003430:Cross-Sectional Studies; D005260:Female; D006761:Hospitals; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D008875:Middle Aged; D010561:Personnel Staffing and Scheduling; D000073577:Shift Work Schedule; D000078329:Workforce
chemical_list: D015415:Biomarkers; D006854:Hydrocortisone
keywords: cortisol; shift work; shift work parameters