Skiftarbeidsordning påvirker søvn og søvnighet hos offshore petroleumsarbeidere 

Arbeiderne jobbet 2 uker dagskift, 2 uker nattskift eller 2 uker svingskift (en uke nattarbeid etterfulgt av en uke dagarbeid).

Resultatene viser subjektiv søvnighet de første dagene med nattarbeid og etter overgang fra nattarbeid tilbake til dag. Det å gå tilbake til dagarbeid etter en uke med nattarbeid hadde i tillegg negativ effekt på søvn. 

Subjective and objective sleepiness among oil rig workers during three different shift schedules

Waage S, Harris A, Pallesen S, Saksvik IB, Moen BE, Bjorvatn B.

Department of Public Health and Primary Health Care, University of Bergen, Norway; Uni Research, Bergen, Norway.

OBJECTIVES: Examine sleepiness in three different shift work schedules (within-subject design) in the offshore oil industry.
METHODS: Sleepiness was measured in 19 oil rig workers, using subjective (Karolinska Sleepiness Scale; Accumulated Time with Sleepiness) and objective measures (reaction time). The work schedule consisted of two weeks of 12h day work (day shifts), two weeks of 12h night work (night shifts), and two weeks of swing shift work (one week of night work followed by one week of day work).
RESULTS: Sleepiness was highest during the first days of night and swing shifts, and also in the middle of the swing shift work period, but gradually decreased as the days on the night shift progressed. While at home following the two-week work period, the workers reported more subjective sleepiness after night shift than after day or swing shifts. Reaction time tests during the work period showed no significant differences between the shift schedules. There was a significant shorter reaction time the last day compared to the beginning or middle of the work period.
CONCLUSIONS: Subjective sleepiness was higher during the first days of night work compared to day work, and also when the swing shift workers changed from night work to day work in the middle of the two-week work period. Subjective sleepiness was increased at home following night shifts compared to after day and swing shifts, suggesting that swing shift workers adapted their circadian rhythm during their second period of work, during the day shift week, offshore. Studien publiseres i Sleep Med. 2011 Oct 25. [Epub ahead of print]


Adaptation and readaptation to different shift work schedules measured with sleep diary and actigraphy

Saksvik IB, Bjorvatn B, Harvey AG, Waage S, Harris A, Pallesen S.

Department of Psychosocial Science, University of Bergen, Bergen, Norway. ingvild.saksvik@psysp.uib.no

In this study we examine sleep during adaptation and readaptation to different shift work schedules in the offshore oil industry. The sleep of 19 offshore workers was assessed daily for 1 week before, during the work period, and for 1 week after 3 different work schedules: (1) day (14 consecutive days of work), (2) night (14 consecutive nights of work), and (3) swing shift work (first 7 nights with night work then 7 days of day work). The workers' sleep was assessed for 84 days. Actigraphy and sleep diary estimates of sleep was applied assessing: (1) adaptation to offshore shift work, (2) sleep across the 2 offshore work weeks, and (3) readaptation after the work period. Regarding adaptation, sleep efficiency was higher when working day than night and swing shift the first week of work. Sleep quality was better during swing than regular day/night shifts the first week of work. Total sleep time was longer during day and night shift than swing shift across the 2 work weeks. Sleep efficiency, based on sleep diaries, was higher during day than night and swing shift during the 2 work weeks. There were no significant differences between the shifts in readaptation in terms of sleep. To conclude, adaptation to swing shift was more difficult than adaptation to regular day and night shifts in terms of sleep. Readaptation to day work after 1 week of night work affected sleep negatively. There were no differences between the shift schedules the week after the work period. Studien er publisert i J Occup Health Psychol. 2011 Jul;16(3):331-44.