title: Locomotive engineers and their spouses: coffee consumption, mood, and sleep reports.
abstract: Locomotive engineers (train drivers) on irregular work schedules reported a general coffee consumption rate higher than that reported by a comparison sample of permanent shift factory workers. The present study examines the impact of this consumption on workday and non-workday sleep behaviour and mood ratings. Twenty-seven engineers and their spouses each completed daily logs for 30 consecutive days. Daily logs were then sorted into workday and non-workday categories. Workday sleep length was significantly shorter than non-workday sleep length for both engineers and spouses. For the engineers only, coffee consumption on workdays was higher than on non-workdays. This increased coffee consumption was correlated with longer sleep latency, increased negative mood, and decreased positive mood on both work and non-workdays. This was not true for spouses. These results may be related to a days-off carry-over effect of caffeine or a general consumption behaviour characteristic.
authors.affiliation: Department of Psychology, University of Connecticut, Storrs 06269-1020.
authors.forename: D K
authors.initials: DK
authors.lastname: Dekker
authors.forename: M J
authors.initials: MJ
authors.lastname: Paley
authors.forename: S M
authors.initials: SM
authors.lastname: Popkin
authors.forename: D I
authors.initials: DI
authors.lastname: Tepas
mesh_terms: D000328:Adult; D000339:Affect / Q000187:drug effects*; D002110:Caffeine / Q000494:pharmacology*; D002940:Circadian Rhythm; D003069:Coffee; D004327:Drinking Behavior; D005260:Female; D006801:Humans; D008297:Male; D008499:Medical Records; D008875:Middle Aged; D011890:Railroads; D012890:Sleep / Q000187:drug effects*; D014940:Work Schedule Tolerance
chemical_list: D003069:Coffee; D002110:Caffeine