SLEEP DISORDERS

Healthy from the Start Resources for Shiftworkers

Sleep disorders are clinically-diagnosed sleep problems that impact how you feel when you’re awake. Sleep disorders come in many different shapes and sizes but are usually more common in shiftworkers. Shiftwork can contribute to sleep problems without causing sleep disorders though, so talk to your GP about your work and your sleep.

Sleep disorders are conditions that disrupt the quality, timing, or amount of sleep you get, leading to distress and decreased functioning when you’re awake (22). There are many different types of sleep disorders - here are some of the most common for shiftworkers (21).

Shiftwork Disorder

Shiftwork disorder (or shiftwork sleep disorder) is caused by ongoing disruptions to circadian rhythms (e.g., regularly being exposed to light, eating, and sleeping at non-traditional times) directly in relation to shiftwork. Both sleep and wake are disrupted beyond what is expected, or ‘normal’ for a shiftworker. It is estimated that around 10% of shiftworkers have shiftwork disorder (23).

People with shiftwork disorder experience (23):

  • Insomnia symptoms; and/or

o    Experienced by over 30% of shiftworkers, insomnia symptoms are characterised by difficulty falling asleep, staying asleep, or non-restorative sleep (24-26).

  • Excessive sleepiness; and

o   Experienced by up to 90% of shiftworkers, excessive sleepiness is characterised by difficulty staying awake and alert, and an increased desire to sleep, during waking periods (24-27).

  • A work schedule that overlaps with your traditional sleep period (i.e., shiftwork).

“ I was amazed that there’s a sleep disorder you can develop specifically from shiftwork – but when you think about having to work against your circadian rhythms and chronotype, it makes sense”.

- Alex, 33, previous shiftworker.

Insomnia

Insomnia is the most common sleep disorder in the world (22), and it’s estimated that up to 75% of shiftworkers experience insomnia at some point in their careers (28). Insomnia is characterised by ongoing difficulties in falling asleep or staying asleep, and flow-on impacts for functioning when you’re awake (e.g., fatigue, mood problems, impaired attention, decreased productivity) (27). To be diagnosed with insomnia, sleep difficulties must occur at least 3 times/week, for at least 3 months, and be causing significant disruptions to your life when you’re awake.

Sleep-Related Movement Disorders

Sleep-related movement disorders (SRMD) are a group of conditions involving repetitive, abnormal movements that interrupt sleep. Common SRMD include (29):

  • Restless Legs Syndrome (RLS)

o  Characterised by discomfort in your legs and an urge to move them while at rest. About half of all people with RLS have a family history of the disorder, but shiftwork can make symptoms worse (30).

  • Periodic Limb Movement Disorder (PLMD)

o   Characterised by involuntary episodes of arm and leg movement which are caused by muscle contractions during sleep. The sleep challenges that shiftworkers face can make PLMD symptoms worse (31).

  • Bruxism

o   Characterised by involuntary grinding of teeth at least once per week, which can show up as pain in your face and neck, or even damage to your teeth (32). Irregular sleep patterns, high stress levels, and consuming a lot of caffeine – things that many shiftworkers experience - can increase your risk of bruxism (33).

 Sleep-Related Breathing Disorders

Sleep-related breathing disorders (SRBD) are a group of conditions where people experience abnormal or difficulty breathing while asleep (34). Common SRBD include (35):

  • Chronic Snoring

o   Snoring occurs when the muscles of your airway relax, and the surrounding tissues vibrate as you breathe in and out. While snoring is common, the severity can vary widely – light, occasional snoring is probably not cause for concern, but frequent, loud snoring may need further investigation. This is because snoring is one of the most common symptoms of obstructive sleep apnoea (36).

  • Obstructive Sleep Apnoea (OSA)

o   Characterised by a complete or partial collapse of your airway while you’re asleep, which can decrease the amount of oxygen in your body (37).

o    OSA doesn’t just cause disruptions to sleep but is also linked with several serious health problems. For example, untreated OSA increases your risk of heart disease, stroke, and diabetes (38,39).

o   OSA is more common than many people realise, with up to half of all adults meeting the criteria for diagnosis (40). Being overweight or obese, and using sedative medications before sleep, both of which are associated with shiftwork, are risk factors for OSA (39).

If you think you’re experiencing a sleep disorder, it’s important to seek help from a healthcare professional – your general practitioner is usually a good place to start. Getting enough quality sleep can help you to feel and perform your best, while poor sleep can have significant, long-term impacts on your health and wellbeing – read more about these impacts here.

Symptoms need to be present for at least 3 months, and not easily explained by another medical condition, to lead to a diagnosis of shiftwork disorder (23).

There are a number of strategies available to manage shiftwork disorder, including behavioural modifications and medications – talk to your healthcare provider if you think you may be experiencing shiftwork disorder (23).