Impacts of sleep on shift workers

Shift workers have more than their fair share of sleep troubles. While many of us regular workers are in bed by midnight during a weekday, shift workers who work outside of the traditional 9am-5pm schedule may be waking at odd hours to take an early morning shift or staying awake all night for a graveyard shift.

It is challenging for them to get good quality sleep because of a few reasons:

1. Irregular night shift schedule
   They may have been assigned schedules that results in switching back and forth between night and day shifts frequently during the week.

3. Poor sleep environment
   Having to sleep in the day means that everyone else are up and about while they are trying to whine down. Loud noises and interruptions from family members, combined with morning sunlight coming into the room, may result in an inconducive environment for sleeping.
4. Exposure to sunlight on the way home
   Those working graveyard shifts will have to travel home in the morning. Being exposed to sunlight will signal to the body that the person should be awake, and this will trigger biological processes to ensure that he or she can stay awake. This is due to our body’s circadian rhythm, and it results in difficulty falling sleep and poor quality sleep.

Needless to say, not being able to get sufficient good quality sleep will have adverse impacts on a shift workers’ health.

Shift work is one of the causes of circadian misalignment, which in turn raises the risk of cardiovascular disease. The body’s circadian rhythm is like an internal clock that tells the body when to sleep, wake and eat. It is influenced by external cues such as sunlight and temperature. Hence, wanting to sleep when the morning sun is signalling to the body that it is time to be awake throws the circadian rhythm off, resulting in circadian misalignment.

This misalignment causes the production of hormones in high concentrations at times when they are not required and in reduced amounts when they are needed the most. This may lead to metabolic and cognitive consequences, and hence increase the risk of cardiac diseases. Circadian misalignment also causes increase in blood pressure and inflammation, both of which are factors for cardiovascular disease.

If shift workers are stressed during their work, it leads to frequent and persistent tachycardia, which refers to a fast resting heart rate, generally over 100 beats per minute. A study monitoring emergency physicians during a 14-hours shift and a 24-hours shift showed that they experienced frequent episodes of tachycardia reaching even up to 180 bpm and the cardiac stress was twice on the shift day compared to the non-shift days.

Furthermore, poor sleep quality can lead to work injuries, especially for those working in high risk occupations such as construction. Research has found that workers with sleep problems are 1.62 times at higher risk of being injured as compared to those without. This is because sleep deprived workers are typically less alert and can cause accidents. They may not adequately react in dangerous situations as well.

With all these risks mentioned above, there are however a few ways that shift workers can manage their sleep quality in order to reduce the impact on their health:

1. Blocking light
   Using heavy curtains to block out sunlight or eye masks while trying to sleep in the day can help signal to the body and its circadian rhythm that it is time for bed.

2. Sunglasses
   To avoid too much exposure to sunlight on the way home, something as simple as wearing sunglasses can help reduce the stimulation coming from the morning sun.

3. Planning caffeine intake
   It is important to take note of when to drink coffee, tea or any foods with caffeine to avoid interruptions with bedtime. Typically, there should not be any intake of caffeinated drinks 4 to 6 hours before bed.

4. Accumulating sleep hours
   The recommended number of hours to sleep for an adult every day is 7 to 9 hours. However, this may not be possible for shift workers who work overnight. It is essential to catch up on the sleep debt and achieve the maximum number of hours of sleep on days off.

Shift workers are already at a higher risk of cardiovascular diseases and workplace injury as compared to regular workers. Hence, it is all the more important to take action now and be extra diligent in optimising everything else to achieve the best quality of sleep. Active Health Coach Mason Tan advises, “Although shift work poses plenty of challenges in many aspects of life, including sleep. There are steps that you can take to improve the quality of your sleep. Take time to try out the various strategies above and see which works better for you!”