Excessive daytime sleepiness is an essential feature of idiopathic hypersomnia, but other key symptoms and aspects of the medical history are crucial when evaluating patients who present with excessive daytime sleepiness. Patients with idiopathic hypersomnia commonly report the following symptoms in addition to excessive daytime sleepiness: severe and prolonged sleep inertia, long and unrefreshing naps, prolonged sleep time, and cognitive dysfunction.

Knowing the key symptoms and utilizing sleep testing can increase a healthcare professional’s confidence in his/her diagnosis of idiopathic hypersomnia.
The Idiopathic Hypersomnia Severity Scale is a 14-item questionnaire that is a clinical tool designed specifically to measure patients’ idiopathic hypersomnia symptoms and provide a touchpoint that might be useful for patient identification, follow-up visits, and idiopathic hypersomnia management.

This episode is produced by Sleep Review. It is episode 1 of a 5-part series sponsored by Jazz Pharmaceuticals. Visit Jazzpharma.com and SleepCountsHCP.com for more information.

In episode 1, listen as Sleep Review’s Sree Roy and sleep specialist Logan Schneider, MD, discuss:

• The symptom of idiopathic hypersomnia that people are most familiar with is excessive daytime sleepiness. Will you define and briefly explain this core symptom?
• But excessive daytime sleepiness is not the only symptom typically reported by people with idiopathic hypersomnia. Prolonged sleep time is another common symptom. What can this mean over the course of a 24-hour day?
• Sleep inertia, that feeling of difficulty waking up, can happen to all of us. How can sleep inertia differ in people with idiopathic hypersomnia versus in those without it?
• Are naps generally restorative for people with idiopathic hypersomnia? Does length matter?
• What ancillary cognitive symptoms are commonly reported with idiopathic hypersomnia?
• In 2019, the Idiopathic Hypersomnia Severity Scale was developed to measure the severity, frequency, and functional impact of the key symptoms of excessive daytime sleepiness, prolonged nighttime sleep, and sleep inertia. What do you think is the clinical utility of this questionnaire?

To dive even deeper:

• https://sleepreviewmag.com/sleep-disorders/hypersomnias/idiopathic-hypersomnia
• Trotti LM. Idiopathic hypersomnia. Sleep Med Clin. 2017;12(3):331-44.
• Dauvilliers Y. Idiopathic hypersomnia severity scale. 2018.
• Arnulf I, Leu-Semenescu S, Dodet P. Precision medicine for idiopathic hypersomnia. Sleep Med Clin. 2019;14(3):333-50.
• Vernet C, Leu-Semenescu S, Buzare MA, Arnulf I. Subjective symptoms in idiopathic hypersomnia: beyond excessive sleepiness. J Sleep Res. 2010;19(4):525-34.
• Dauvilliers Y, Evangelista E, Barateau L, et al. Measurement of symptoms in idiopathic hypersomnia: The Idiopathic Hypersomnia Severity Scale. Neurology. 2019;92(15):e1754-62.
• Rassu AL, Evangelista E, Barateau L, et al. Idiopathic Hypersomnia Severity Scale to better quantify symptoms severity and their consequences in idiopathic hypersomnia. J Clin Sleep Med. 2022;18(2):617-29.