Sleep Medicine MOC Sample Questions

The correct answer is B. Change to day shift schedule

Explanation: This patient has a diagnosis of SWD. The fundamental problem in SWD is a mismatch between the patient’s circadian phase and work schedule such that the patient is working during their biological night and attempting to sleep during their biological day. SWD affects between 10% and one-third of shift workers; thus, there seems to be significant inter-individual variability in tolerance to shift work and vulnerability to SDW. It is known that morning-types (individuals with a relatively advanced circadian phase) are more vulnerable to SWD than evening-types (individuals with a relatively delayed sleep phase). Potential treatments for SWD include those aimed at the symptoms of sleepiness and insomnia (i.e. stimulants, hypnotics) and those aimed and the circadian mismatch. This latter category includes treatment aimed at shifting the patient’s circadian phase (light therapy, darkness during the day and melatonin) which would likely only partially benefit this patient due to the fact that he returns to a conventional sleep wake schedule on his days off. This day to day change in his sleep schedule is likely part of the reason he has not “adapted” to the frequent night shifts as he supposed he would. The most effective treatment measure in this patient would be to change to day shifts. This would resolve the fundamental pathological problem in SWD which is the mismatch between the patient’s circadian phase and work schedule. The fact that all of his symptoms resolved on vacation with an ad-lib sleep schedule supports this treatment measure. While hyptnotics and stimulants may address the specific symptoms of SWD they do no address the circadian mismatch. As noted above, attempts to shift this patient’s circadian phase to match his work schedule would likely be compromised by his returning to a normal schedule on days off.