Managing Shift Work
Millions of people work the night, or “graveyard,” shift (11:00 P.M. to 7:00 A.M.) or rotate among day, evening, and night shifts. More than half of these workers experience sleep difficulties. Studies demonstrate that shift workers experience poorer sleep quality, shorter sleep, and more difficulty falling asleep and staying asleep than regular day workers.
Why is shift work associated with such a high incidence of sleep problems? Recall from chapter 2 that body temperature, which plays an important role in promoting sleep and wakefulness, is directly influenced by the daily cycles of light and darkness. Light causes body temperature to rise (which promotes wakefulness), while darkness causes temperature to fall (which promotes sleep). Thus, night and rotating shift workers are more prone to sleep disturbances because they must usually sleep during the day—the time when nature intended us to be awake.
Shift workers must also work when our bodies were designed to be asleep. Consequently, they are more likely to be drowsy or fall asleep during work. Studies have shown that 75 percent of night workers feel drowsy at work and that over half admit to falling
asleep on the job. (In fact, it is not uncommon for night workers to doze off while driving home from work.)
Reduced alertness on the job impairs performance, productivity, and work quality and increases chances of error, safety problems, and on-the-job accidents. In fact, a number of serious industrial accidents have been related to fatigue and sleepiness during the night shift. The near meltdown that occurred in 1979 at the Three Mile Island nuclear power plant occurred at 4:00 A.M. and involved a work crew that had just changed to the graveyard shift. Other accidents attributed to shift work include the Exxon Valdez oil spill and the Chernobyl nuclear disaster.
Shift workers report higher levels of job dissatisfaction, absenteeism, and low morale. Shift work is associated with increased use of sleeping pills and alcohol to aid sleep as well as stimulants such as caffeine to stay awake. Mood and general health and well-being are poorer and levels of stress are higher among night and rotating shift workers compared to day workers.
Because someone on the graveyard shift has less time to spend with a spouse and children, marital and family relationships suffer. When shift workers try to socialize with family and friends on days off, they often lack the energy and enthusiasm to enjoy social interaction. And since there is less time to socialize in general, social isolation and loneliness become problematic.
Working the night shift is difficult enough, but rotating among day, night, and evening shifts is worse; it is like working for a week in the United States, a week in Europe, then a week in Asia—a type of jet lag without flying. When the body must quickly adjust to a new waking and sleeping schedule, it never has a chance to adjust to one shift and establish a consistent body-temperature rhythm.
When rotating shifts are repeated month after month, the resulting chronic disruption in the body-temperature rhythm almost guarantees disturbed sleep and reduced alertness. Consequently, those on rotating shifts encounter even greater disruptions in sleep, alertness, and mood than regular night shift workers.
Some people adjust more easily to shift work than others; it is hardest on insomniacs, who have a sensitive sleep system to begin
with, and older people, whose body-temperature rhythms have a harder time adjusting than those of younger people.
If you work the night shift, the following guidelines will minimize its deleterious effects:
1. Try to maintain the same sleep-wake schedule on your days off. This will give your body regular cues (such as a consistent rising time and regular periods of physical and social activity) that will synchronize your body-temperature rhythm. Unfortunately, this practice is difficult for most shift workers since they socialize on a conventional schedule on their days off.
2. When leaving work in the morning, wear dark glasses to prevent sunlight from causing your body temperature and alertness level to increase.
3. Allow sufficient time to wind down after work. If you get off work at 7:00 A.M., do not attempt to go to sleep at 8:00 A.M.
4. Ensure that your sleep will not be interrupted by light, door-bells, telephones, noises from the street, or people. Darken your bedroom by using dark drapes or an eyeshade. Don’t let children, your spouse, or the telephone interrupt your sleep. Use a sound conditioner, fan, or earplugs to reduce noise and place rugs on wooden floors to deaden the sound of footsteps. Review chapter 7 concerning other guidelines for creating an optimal sleep environment.
5. Practice the techniques in this program for improving sleep; they will minimize the sleep disruptions caused by night work.
6. Get together with your coworkers and suggest to your employer that your work environment be equipped with bright light. Bright light increases alertness and performance on the job (which may increase your employer’s profits and compensate for the cost of the lights); it also synchronizes the body-temperature rhythm so that you will sleep better during the day.
The deleterious effects of rotating shifts can be minimized by preparing for a shift change in advance; that is, by adjusting bedtimes and wake-up times a few days prior to the new shift. For example, a few
days before switching from the evening shift (3:00 P.M. to 11:00 P.M.) to the night shift (11:00 P.M. to 7:00 A.M.), set bedtimes and wake-up times a few hours later; when changing from the night to day shift, move bedtimes and wake-up times a few hours earlier. Expose yourself to bright light when you rise from bed and during work to promote wakefulness.
Rotating shift workers should also avoid exposure to bright light during the few hours before bedtime so that the body doesn’t think it is time to wake up. Sleep disruptions from rotating shifts can also be minimized by paying particular attention to creating an ideal sleep environment and practicing all the techniques in this program for improving sleep.