A 49-year-old registered nurse comes to the office due to sleep difficulties since receiving a promotion to an administrative position in the hospital several weeks ago. She finds her new job and its many responsibilities stressful. Her sleep schedule changed when she took the new position; she used to work the 4:00 PM-12:00 AM shift and had no sleep difficulties. Now she has to be at the hospital by 7:30 AM. The patient cannot fall asleep until 2:00-3:00 AM. She then awakens by alarm at 6:15 AM to get to work on time. She is exhausted all the time and has trouble concentrating and staying awake during meetings. The patient is increasingly frustrated by her sleep problems, which have occurred in the past with jobs or schooling requiring early start times. The patient has the same difficulty initiating sleep before 2:00-3:00 AM on weekends but feels better then as she is able to sleep without interruption until 11:00 AM. She does not use tobacco or alcohol. Which of the following is the most likely cause of her sleep difficulties?

Question

A 49-year-old registered nurse comes to the office due to sleep difficulties since receiving a promotion to an administrative position in the hospital several weeks ago.  She finds her new job and its many responsibilities stressful.  Her sleep schedule changed when she took the new position; she used to work the 4:00 PM-12:00 AM shift and had no sleep difficulties.  Now she has to be at the hospital by 7:30 AM.  The patient cannot fall asleep until 2:00-3:00 AM.  She then awakens by alarm at 6:15 AM to get to work on time.  She is exhausted all the time and has trouble concentrating and staying awake during meetings.  The patient is increasingly frustrated by her sleep problems, which have occurred in the past with jobs or schooling requiring early start times.  The patient has the same difficulty initiating sleep before 2:00-3:00 AM on weekends but feels better then as she is able to sleep without interruption until 11:00 AM.  She does not use tobacco or alcohol.  Which of the following is the most likely cause of her sleep difficulties?

Quizplus · Accepted Answer

This patient's lifelong pattern of sleep difficulties that occur when her work or school schedule requires an early rise time is consistent with delayed sleep-wake phase disorder (DSWPD). DSWPD is a circadian rhythm sleep-wake disorder characterized by sleep-onset insomnia and excessive morning sleepiness. When the patient is allowed to follow her natural circadian rhythm on the weekends, her sleep is normal in duration and quality (ie, she sleeps without interruption until 11AM and awakens feeling well-rested). Whereas her previous work schedule (4:00 PM-12:00 AM) was aligned with her natural circadian rhythm, her new work schedule, requiring a rise time of 6:15 AM, is not. Circadian rhythm sleep-wake disorders occur when the internal clock regulating sleep and wakefulness is misaligned with a person's desired sleep time or social/professional schedule. Patients with DSWPD commonly describe themselves as "night owls" and have chronic problems going to sleep at a conventional time (typically, prior to midnight). They sleep normally when allowed to set their own schedule. The onset of the condition occurs in adolescence and may respond to treatments such as light or behavioral therapy. (Choice A) Advanced sleep-wake phase disorder is another circadian rhythm disorder characterized by the inability to stay awake in the evening (usually after 7:00 PM) and by early morning insomnia. (Choice C) Decreased levels of melatonin, a finding associated with normal aging, may cause sleep disturbances. Levels that exceed the drop seen in normal aging have been described in dementia. However, this patient's relatively young age and normal sleep on weekends make this diagnosis less likely. (Choice D) Sleep hygiene is defined as behaviors that promote improved quantity and quality of sleep (eg, regular sleep and wake times, avoiding naps, refraining from stimulating activities and caffeine prior to sleep). This patient reports no significant behaviors that appear to compromise her ability to initiate sleep. (Choice E) Shift work disorder involves a recurrent pattern of sleep interruption due to shift work, causing difficulty in initiating and maintaining sleep and producing daytime sleepiness. This disorder is due to a work schedule that is incongruent with a normal circadian clock (eg, a patient with a normal circadian rhythm who is required to work the night shift). In contrast, this patient has an abnormal internal circadian rhythm (ie, DSWPD) that has created difficulties throughout her life (eg, jobs with conventional morning start times, school). Educational objective: Delayed sleep-wake phase disorder is a circadian rhythm disorder characterized by the inability to fall asleep at traditional bedtimes, resulting in sleep-onset insomnia and excessive daytime sleepiness. Patients sleep normally if allowed to follow their internal circadian rhythm and sleep until late morning. References: Diagnosis, cause, and treatment approaches for delayed sleep-wake phase disorder. (http://www.ncbi.nlm.nih.gov/pubmed/27542884)

A 49-Year-Old Registered Nurse Comes to the Office Due to Sleep