One of our primary objectives in a behavioral sleep medicine practice is to accurately diagnose a patient so that we can provide the most appropriate treatment. Often times, diagnosis is more complicated than our manuals would lead us to believe. One distinction that can be particularly cumbersome is the differentiation between insomnia disorder and delayed sleep phase disorder. Many times patients present with very similar symptoms, and clinics do not often have the resources to obtain biological measures of circadian rhythms (e.g., dim light melatonin onset) to aid in diagnosis.
This issue was the topic of a workshop at this year’s sleep conference entitled “Is it Insomnia or Delayed Circadian Rhythm or Both? How to Diagnose and Treat.” Drs. Shea Golding and Hovig Artinian reviewed in detail the challenges of this differential diagnosis in both children and adults, and discussed implications for treatment. There is significant overlap between these two syndromes and this can make accurate diagnosis challenging. There are established treatments for both disorders, but less evidence for how and when to treat circadian rhythm disorders. CBT-I and chronotherapy were reviewed, in addition to the use of bright light and melatonin in treating delayed sleep phase. Often these approaches are combined to craft a treatment that is going to be both effective and acceptable to the patient. Chronotherapy is challenging and requires strict adherence from patients, but can be highly effective if used correctly. CBT-I can be used in combination with shifting a patient’s schedule to avoid the development of conditioned arousal in bed. Morning bright light and evening melatonin can also facilitate a shift in schedule, but there is not much evidence regarding dose and timing of these strategies. To summarize, it can be challenging sometimes to differentiate between a delayed circadian rhythm and insomnia disorder; however, effective treatments can be provided even if the diagnosis is not completely clear.
Drs. Golding and Artinian highlighted some of the main differences to look for when differentiating between insomnia disorder and delayed circadian rhythm, including (but not limited to) duration and quality of sleep at a later schedule, weekday vs. weekend (or school break) discrepancies, quality of time awake (frustrated and trying to sleep, or awake and bored). They also highlighted several treatment options including CBT-I, chronotherapy, bright light, and melatonin. This workshop was a great reminder that not all cases are clear-cut, but that doesn’t necessarily mean that treatment will not be effective. We have a plethora of treatment options to choose from, and they can be used in combination to produce the best outcomes for our patients.
Leisha Cuddihy, PHD, DBSM