A 31-year-old woman is in your office complaining of insomnia and excessive sleepiness during work periods. She is currently in the first month of her medical residency at an East coast medical school and is at the end of her 4 week stint on the night float rotation. The previous month she went on a graduation trip to Orlando, Florida where she spent 5 days. During this trip she stayed up until 1am on most nights and slept until 8am. She reported feeling fine after the trip concluded and was eager to begin her internship. It was after beginning work that she started to experience these symptoms.
She describes her symptoms as an inability to fall asleep when she tries to, which is usually around 9am, and estimates that in total she probably get 6.5 to 7 hours of sleep per day. Her excessive sleepiness then occurs throughout the night during activities that require her fullest attention. She has become worried about her ability to care for patients appropriately, and this has begun to cause her some emotional difficulty. But she is encouraged by favorable remarks by her supervising faculty thus far.
On examination she is a normal appearing adult female with a BP of 125/78, pulse 78, RR 15 and BMI of 25.6 kg/m2. Her physical examination reveals a patient who generally appears tired and yawns excessively during the interview. Otherwise her examination is normal, including oropharynx and neck circumference.
Which of the following is the most likely diagnosis?
A. Chronic sleep deprivation
B. Jet lag
C. Opiate withdrawal
D. Shift work sleep disorder
E. Obstructive sleep apnea
F. Adjustment disorder with depressed mood
Correct answer: D – Shift work sleep disorder
Key Point: Insomnia and excessive sleepiness can result from disruptions in the circadian rhythm.
Discussion: Shift work sleep disorder and jet lag are the most common types of circadian rhythm sleep disorders and can appear similar to each other during patient assessment. The history of either a work schedule occurring during non-working hours or airline travel to a distant time zone is essential. For significant jet lag to occur the time zones need to be greater than 5 zones apart. In the question stem the east coast location is likely in the same zone as Orlando, Florida (Eastern Time zone) so jet lag is very unlikely.
Chronic sleep deprivation is a common cause of excessive sleepiness but is less likely than shift work in this typical scenario described in the question stem. Additionally she is getting a significant amount of sleep if her estimations are accurate. A sleep diary would help confirm this.
Her near normal BMI, normal exam and timing of symptoms argue against obstructive sleep apnea, although it is possible to suffer from OSA with a normal BMI and exam.
Opiate withdrawal is associated with excessive yawning and medical personnel may have increased access to prescription strength narcotics but there is no other reason to suspect this diagnosis in this patient.
Adjustment disorder with depressed mood requires significant impairment in social or occupational functioning as a result of a new stressor. This patient appears to be functioning well enough at work to receive praise from her supervisors making this diagnosis less likely.
Shift work sleep disorder may be treated with bright light treatment, caffeine or other stimulants and planned napping during work hours if allowed.
Yazdi, et al. Prevalence of Sleep Disorders and Their Impacts on Occupational Performance: A Comparison between Shift Workers and Nonshift Workers. Sleep Disorders, 2014.