Shift Work Sleep Disorder: A Condition with Wide-Ranging Effects on Health, Job Performance and Daily Life
Life isn’t fair to “night owls”—people who prefer to go to bed late and sleep late in the morning, or who work the night shift. Everything tends to be structured around the needs of people who work from 9 to 5. Businesses, schools and city services usually close their doors at 5:00, 6:00 or 7:00 p.m. at the latest.
But night owls are hardly rare in our society. More than 22 million Americans work evening, night, rotating or on-call shifts. If you’re one of them, you may find it challenging to keep up with your family and friends. Organizing your time, your responsibilities and your activities outside of work can be challenging as well.
“Overnight shifts are especially common in the health care field,” notes Dr. Daniel Barone, Associate Medical Director of the Center for Sleep Medicine and Associate Professor of Clinical Neurology at Weill Cornell Medicine. “Consider the nurse who works from 7:00 p.m. to 7:00 a.m. She gets home at 7:30 or 8:00 a.m., just when the sun signals to her body that it’s time to start the day. But for her, along with many doctors, firefighters, soldiers and police officers, getting up and going to sleep are upside down.”
Shift work sleep disorder
Some people can handle the physical effects of shift work better than others, Dr. Barone says. But at least half don’t adapt well to its demands, especially when it comes to sleeping when the rest of the world is awake. Shift work often comes with a hefty price tag in the form of poor quality or inadequate sleep, known as shift work sleep disorder.
Your internal clock is set at 24 hours, and ideally, you need to spend 8 of those hours sleeping. However, that’s only part of the equation, he says. “Those 8 hours normally need to take place during the proper window. Most of us sleep when it’s dark and get up shortly before or after sunrise. If you work the night shift and you need to sleep during the day, the sun works against you, fighting your body’s natural desire to sleep when it’s dark.”
Sleep deprivation
National data collected by the National Institute for Occupational Safety and Health (NIOSH) show that more than 50 percent of night shift health-care workers sleep 6 or fewer hours a day. That’s not enough, says Dr. Barone, who recommends at least 7 hours of sleep a day.
Getting less sleep than needed is called sleep deprivation. Not only do people feel tired and unrefreshed when they’re sleep deprived, but they can also show declines in brain functioning, such as response rate, thinking, remembering and concentration.
They also face a variety of risks to their physical health.
Impact on health
According to NIOSH, shift workers may be at higher risk for:
- Cardiovascular disease
- Gastrointestinal disorders
- Psychological disorders
- Cancer
- Type 2 diabetes
- Adverse reproductive outcomes
Studies also show that night shift workers are prone to eating more junk food than their day shift counterparts. Excessive junk food consumption can cause hormone imbalances, leading to obesity and inflammation.
One hormone found to be abnormally high in sleep-deprived shift workers, Dr. Barone explains, is cortisol. Produced by the adrenal glands, cortisol is responsible for the “fight-or-flight” response you experience when you’re suddenly faced with a threat to your safety. High levels of cortisol can help us outrun a mugger but can’t get us through the lower-stress demands of daily life. In the long run, chronically elevated cortisol wreaks havoc with our mental and physical health.
Despite the positive role cortisol plays in many bodily functions, too much of a good thing can raise your blood sugar. That’s why sleep-deprived night shift workers may develop hyperglycemia (high blood sugar) and, over time, type 2 diabetes.
Sleep deprivation and job performance
In addition to the effects of sleep deprivation on your physical health, it can impair your performance at work:
- Some tasks require intense concentration, and you can’t summon the necessary attention to perform them well.
- Under time pressure, your response rate may slow down, which can lead to errors.
- You find yourself making more and more of an effort to remain effective on the job.
Commuting to and from work can be problematic too, as traffic accidents are likelier to happen when you’re sleep deprived.
Tips for improving the quantity and quality of your sleep
The Sleep Foundation offers the following suggestions to shift workers seeking to improve their sleep:
- Maintain sleep consistency. On your days off, stick with the same sleep-wake schedule that you observe on work days.
- Enlist the aid of your partner, children, roommates and anyone else under your roof. Make sure they understand the importance of your designated sleep time.
- Control your exposure to light and noise during the day. Block sunlight en route home—wear sunglasses, for instance—and once you get there. Keep your shades down and sleep with an eye mask. And turn off all your devices. Use earplugs or a white noise machine to block outside sounds. Conisder turning off your phone before sleep, unless you’re on call.
- Before going to bed, relax with a hot bath or shower or meditation.
- But avoid alcohol. It may help you fall asleep more easily, but its sedative effects won’t last. You may experience sleep disturbances as your body breaks down the alcohol.
- Try taking melatonin.
Dr. Barone elaborates on this last tip: “Let’s go back to the example of the nurse who works from 7:00 p.m. to 7:00 a.m. On the train home—but not while driving—she can take melatonin in preparation for sleep. The body naturally produces melatonin—often called the sleep hormone—but it is also sold as a dietary supplement that can help with sleep difficulties.”
If none of these measures work, Dr. Barone will perform a sleep test to rule out other problems, such as apnea and narcolepsy.
As for sleeping pills, “these may offer temporary relief,” he says, “but they can’t reset your body’s internal clock. They also tend to become less effective over time. We can keep them in mind as a short-term option.”
Tips for staying awake during shift work
- Use caffeine carefully and in moderation. The Sleep Foundation recommends a cup of coffee or caffeinated soda at the start of your shift. The caffeine will take effect within 15 to 20 minutes. Moderate amounts of caffeine every 1 to 2 hours is more effective than heavier amounts all at once. Avoid it, though, within 4 hours of bedtime. Otherwise, it may interfere with your ability to fall asleep after you get home.
- Get moving. If you have time during a break, consider a brief workout or a jog around your workplace.
- “Bank” some sleep by grabbing a 30-minute nap before work, or a longer nap in the afternoon, if you have time. You can also catch a nap during your break if you’d rather sleep than exercise. Or consider a “coffee nap”: drinking a cup of coffee and then taking a nap that lasts 15 to 20 minutes. You’ll wake up just when the caffeine starts to kick in.
The art and science of sleep
“We’re a sleep-deprived society, Dr. Barone says. “We sleep one hour less than people did 100 years ago.” Even if you aren’t a shift worker, he adds, you would do well to make sleep a priority, and organize your home and work life to promote good-quality sleep. Your health, job performance and personal life depend on it.
Whether you’re a night owl or a lark, Dr. Barone’s latest books on the art and science of sleep are well worth a look-see. The first is Let's Talk about Sleep: A Guide to Understanding and Improving Your Slumber, which discusses what’s known about sleep, what can go wrong with it and what can be done to fix it. And the second, titled The Story of Sleep: From A to Zzzz, is a lively dictionary of topics related to sleep. The book is designed to help people help themselves by improving their sleep.
Make an appointment with a specialist by visiting the Center for Sleep Medicine’s website.