9
AASM Membership Sections Newsletter
■
Issue #6
Circadian Rhythms Case
By Dr. Cathy Goldstein, MD
Mr. D is a 50 yo M with asthma, GERD, and moderate obstructive sleep apnea. He
presents to clinic for follow up of obstructive sleep apnea. At his prior visit, 6 months ago,
he had excellent compliance with CPAP. At that time he did not have daytime sleepiness or
insomnia. At the current visit, he notes excessive sleepiness to the extent that he nods off
at his desk at work. Additionally, he has marked difficulty remaining asleep with frequent
awakenings after sleep onset and difficulty returning to sleep after these awakenings. There
were no weight or health changes between his last appointment and current follow-up visit.
He has no complaints in regards to his CPAP pressure or CPAP mask fit. His bedpartner
denies the re-emergence of snoring or breathing pauses during sleep. CPAP download
demonstrates excellent compliance and efficacy: 30/30 days used, average daily use 8h
39minutes, AHI=2.4
Detailed CPAP download demonstrates the following:
On further inquiry, the patient reveals that his job schedule has changed from day shifts
only to day shifts alternating with night shifts. He has no daytime sleepiness or insomnia
when working day shifts. However, when working the night shift (10PM-6AM) he is very
sleepy during his shift and has difficulty remaining asleep during the allotted daytime sleep
period. On days off, he reverts to a day wake, night sleep schedule. For the next few months,
his supervisor will have him on night shifts only. He works 5 days followed by 2 days off. He
cannot maintain a day sleep, night wake schedule on his days off due to family and social
obligations. I recommended the following: bright light exposure during the first half of the
night shift, avoid bright light with dark sunglasses on the commute from work to home, and
melatonin 1mg before the day sleep period. After his last shift, he should not take melatonin
and should shorten sleep period to 7AM-1PM. He will maintain a delayed sleep schedule
(3AM-11AM) on his nights off.
This case demonstrates a clinical history consistent with shift work disorder and uniquely,
a CPAP use pattern supportive of his insomnia symptoms during the day sleep bout.
Additionally, it highlights shift work treatment principles including the compromise position
described by Smith, et al1.
References
1. Smith MR1, Fogg LF, Eastman CI. A compromise circadian phase position for permanent
night work improves mood, fatigue, and performance.Sleep. 2009 Nov;32(11):1481-9.
Shelley Knowles, MD, FAASM
Dr. Shelley Knowles, MD, FAASM,
is a Clinical Assistant Professor
of Medicine in the Division of
Pulmonary, Critical Care and Sleep
at Wayne State University School of
Medicine. She is board-certified in
Neurology and Sleep Medicine. Dr.
Knowles practices at the John D.
Dingell VAMC in Detroit, MI, and has
a special interest in circadian rhythm
sleep-wake disorders. Her current
research on sleep, inflammation and
telomere length is supported by a
grant from the Metropolitan Detroit
Research and Education Foundation
(MDREF). Dr. Knowles was awarded
the “Attending of the Year” award by
the WSU 2013-14 sleep fellowship
graduating class. ■
