Shift-work sleep disorder (SWSD) is a condition that affects workers who perform changing shifts or work at night. Nearly 20 percent of the U.S. workforce takes part in shift work, which goes against a person’s natural circadian rhythm. SWSD develops as a result of recurrent sleep disruptions and is most commonly seen among individuals who work between 10:00 p.m. and 6:00 a.m.
People with SWSD have difficulties falling and staying asleep, and they often don’t feel refreshed even after they have slept.
Our bodies know when to sleep and wake by following the cycle of the sun and moon. During the day, we are awake, and the setting of the sun signals our body to produce melatonin which makes us tired at night. Those who work the night shift or shift work see more darkness than light and have to be awake when the moon is out, which confuses their circadian rhythm. Furthermore, it can be quite difficult to fall asleep once the individual returns home because the sun is out. If they keep their home completely dark, they would have spent 24 hours in darkness, which leads to further confusion for the circadian rhythm.
SWSD isn’t just a problem for those who work overnight. It can affect people who begin work early in the morning when the sun isn’t out yet.
Although anyone who does shift work or the night shift may be susceptible to SWSD, not all workers experience it. Here we will outline the symptoms, causes, diagnosis, and give you additional facts about SWSD.
How shift work disorder affects sleep
The body typically fits into a 24-hour cycle, which is split between day and night. What affects your ability to sleep or stay awake is exposure to external light. Even if you don’t do shift work or night shifts, you may have experienced similar problems during the winter months, when sunlight exposure is limited. You may feel tired and fatigued throughout the day as a result of low sun exposure.
In the case of SWSD, sleep problems arise because of a mismatch between the body’s biological sleep-wake cycle and the schedule that is required to do your job. Therefore, when you’re done work and it’s time to go home to sleep, you’re exposed to the sun which will make it difficult to sleep.
Health care, law enforcement, transportation, and virtually every industry has shift work that can affect a person’s sleep schedule. According to the latest data from the Bureau of Labor Statistics (BLS), roughly 15 percent of the country’s full-time wage and salary works follow some sort of shift work schedule.
Having irregular hours is the main factor affecting body’s sleep cycles, but in today’s modern world of convenience, there are jobs that requiring serving customers at all hours of the night. Night shift work may actually be ideal for some, as adults with young children or college students may find it more convenient not having a traditional work day.
Common causes of shift work sleep disorder
Shift work disorder disrupts the natural biological processes and the circadian rhythm—your body’s natural 24 hour cycle. There are many factors that lead to its development:
Shift work: For which the disorder was named after, as having night shifts or a constant rotation of shifts leads to a circadian rhythm disruption. Staying awake at night rather than sleeping is the main hallmark of shift work disorder.
Sunlight: A factor that plays a huge role in causing shift work disorder. When the sun starts the day, it stimulates the brain, letting it know it has to stay awake. When the sun sets, it also tells the brain to rest. The sun can be a major hindrance for shift workers who try to sleep during the day.
Circadian rhythm disruptions: Circadian rhythm is the body’s 24-hour cycle, and it involves a combination of hormonal changes, neurotransmitter changes, and brain activity. Under normal circumstances, your circadian rhythm is responsible for helping you sleep and waking up.
Suprachiasmatic nucleus (SCN): A part of the brain that is responsible for maintaining circadian sleep rhythms at night. This specific region is located in the anterior hypothalamus. It synchronizes itself with the time of day. If may be helpful to think of this part of the brain as a biological timekeeper.
Melatonin: A hormone produced by the body that influences the suprachiasmatic nucleus (SCN). When light enters the eye, it signals the SCN to stimulate the penial gland to produce melatonin. Inadequate melatonin production leads to sleeplessness.
Shift work sleep disorder symptoms
Symptoms of shift work sleep disorder include excessive sleepiness during times when you should be awake and alert, insomnia or the inability to sleep when you need to, sleep that leaves you unrefreshed upon awakening, difficulty concentrating, lack of energy, irritability or depression, and difficulty with personal relationships.
Short-term health effects:
- Gastrointestinal symptoms such as diarrhea, nausea, constipation, and upset stomach
- Decreased quality of life
- Increased risk of on-the-job and vehicle accidents
- General feelings of ill health
Long-term health effects:
- Increased risk of cardiovascular disease
- Diabetes and metabolic syndrome
- Depression and mood disorders
- Serious gastrointestinal problems
- Higher chances of getting colds or the flu
- Menstrual irregularities and fertility problems
Shift work sleep disorder affecting your health
Sleep is an integral part of health, as it is the time of day that the body restores itself. Many aspects of health can be affected by impaired sleep, including increased stress (which weakens your immune system), increased risk of accidents due to an inability to concentrate and pay attention, increased risk of sickness, and disrupted production of melatonin (which helps us fall and stay asleep).
Poor sleep has also been linked to memory problems, high blood pressure, weight gain, and other cardiovascular-related problems.
Diagnosing shift work sleep disorder
If your doctor suspects you suffer from shift work sleep disorder, they will ask you to keep a sleep journal and have you do sleep tests. Your doctor will also ask you questions about your shift work and lifestyle.
In your sleep journal, you will need to document how much sleep you are getting and how you feel upon awakening. This information should be collected for a couple of weeks.
The sleep studies will need to be conducted in a sleep lab. In addition, if your doctor suspects SWSD, you may need to undergo a test known as actigraphy, where you will wear a device on your wrist—similar to a watch—that measures your movements. The data collected from this device will reveal to the doctor your daily activity, including when you are awake and when you are asleep.
Coping with shift work sleep disorder: Guidelines for a better sleep
Depending on our own personal circumstances and work life, it may be difficult to choose when you can schedule your shifts. Knowing this, you may face many challenges when working non-traditional hours. This may affect your home and family life, making you feel disconnected from the people you care about the most. Not only this, but your health is at risk, as you are more likely to become sick when fatigued.
For some people, working irregular hours is ideal as they have gotten used to it. For others, it can be a detriment to their lives on all levels. If possible, try to get work shifts during the day.
If there is no other way around taking the night shift, taking a 90-minute nap before your shift can help you stay awake and be more alert. It is also beneficial to take a short nap during break time—about 15 to 20 minutes should be enough to become fully alert.
It is also recommended to eat well. Three meals a day spaced evenly throughout the course of the day. This helps your body get the nutrients it needs, as it is being put through an abnormal amount of stress it is not used to. Avoid drinking alcohol within three hours of your bed time. While it may make you go to bed quicker, you will not get the restful quality sleep you need.
Here are some additional tips that can help you improve your sleep, even if you have shift work sleep disorder.
- Maintain a sleep diary to track your progress
- If possible, decrease the number of night shifts in a row
- Avoid extended work hours
- Avoid long commutes
- Avoid frequently rotating shifts
- Catch up on sleep on your day’s off
- Plan a nap prior to your shift
- Utilize caffeine only during waking hours and not close to when you need to sleep
- Get appropriate light exposure
- Adhere to a healthy lifestyle of regular exercise, eating well, not smoking, and minimizing alcohol intake
- When sleeping, ensure your room promotes good quality sleep, which means it’s dark, quiet, comfortable, and cool
By following these tips, you’ll be able to improve your sleep. If the problem is persistent, you will need to talk to your doctor about other remedies or try or obtain a job with more regular hours.
Related: Why it’s so important to get a good night’s sleep