Shift work disorder is a circadian rhythm sleep disorder that largely affects people who work night, early morning, or rotating shifts. The condition is characterized by insomnia symptoms and/or excessive sleepiness when the person is awake. Recent estimates suggest as many as 20% of shift workers in industrialized countries experience shift work disorder.
Long-term complications of this disorder may include irritability and mood changes, impaired social function in and out of the workplace, and depression. Shift work can also affect hormones such as cortisol and testosterone in some people. People with shift work disorder are also at higher risk of committing errors or accidents while on the job. In order to treat this condition, shift workers should seek out a diagnosis from their doctor or another credentialed physician with a background in sleep health.
According to the American Academy of Sleep Medicine International Classification of Sleep Disorders (Third Edition), criteria for a shift work sleep disorder diagnosis are as follows:
A diagnosis will require a physical exam to rule out any other illnesses or conditions that could be causing these symptoms. Many patients with shift work disorder are diagnosed based on their sleep history. For a period of 14 days, they report sleep-wake patterns and activities using a sleep log.
If available, the patient will also be asked to conduct actigraphy tests at home. This type of non-invasive and painless testing requires them to wear a sensor on their wrist or ankle day and night for 14 consecutive days. For best results, actigraphy tests should be conducted alongside light exposure measurements.
Evaluating patients during work days and days off is crucial for the diagnosis. If sleep log reports and actigraphy tests indicate a disturbed sleep and wake pattern, then the patient may receive a shift work disorder diagnosis. Alternatively, additional tests may be needed to determine whether the patient has another condition that is causing their symptoms.
If you show signs and symptoms of shift work disorder, your doctor may order one or both of the following tests:
Additional tests are usually ordered if the doctor performing your initial exam cannot provide a shift work disorder diagnosis. Conditions that produce similar symptoms to shift work disorder include insomnia, obstructive sleep apnea, narcolepsy, and other circadian rhythm disorders such as delayed sleep-wake phase disorder.
Many people with shift work disorder will experience fewer symptoms after changing to a more traditional schedule that allows them to work during the day and sleep at night. Symptoms that persist after a schedule change may indicate chronic insomnia independent of shift work disorder.