The main symptom of Idiopathic Hypersomnia (IH) is an overwhelming need for excessive sleep. Despite adequate and often extraordinary amounts of good quality sleep (e.g., 10–11 hours or more per night), people with IH are in an almost constant state of sleepiness. But IH is much more than that. IH can cause a range of debilitating symptoms. BRAIN FOG
IH affects cognitive function: including problems with memory, concentration and attention.
SLEEP DRUNKENNESS
People with IH can experience extreme and prolonged difficulty waking up with an uncontrollable desire to go back to sleep. Accompanied by confusion, irritability and poor coordination. Speech may also be slow or slurred.
They can sleep through multiple alarms or will turn them off or answer their phone and will then return to sleep without ever knowing they have woken up.
Because of the extreme effects of sleep drunkenness people with IH often need to be woken by someone who ensures that they take their medication and remain awake.
HYPERACTIVITY
People with IH can develop ADHD like symptoms, eg: fidgeting and talking a lot, to help cope with the immense sleep pressure.
Other symptoms
People with IH may also experience headaches, and problems with autonomic dysfunction, eg: dizziness on standing, and temperature regulation. These symptoms have been recorded in various studies (see references below). More recently, the results of ARISE, a US-based cross-sectional survey comprising multiple patient-reported outcome measures was published.
The study gained insights into the impact of Idiopathic Hypersomnia on the daily functioning and quality of life of individuals diagnosed with this disorder. ARISE assessed various aspects, including daily functioning, relationships, cognition, emotional well-being, and productivity/employment, among participants with Idiopathic Hypersomnia.
Some words from the study report:
“This study highlights the association of idiopathic hypersomnia with impairments in daily functioning, social aspects, cognition, affect, and work productivity. An important point is that these impairments were observed despite most participants (89.3%) taking off-label medications to treat idiopathic hypersomnia, primarily stimulants, wake-promoting agents, and antidepressants. This suggests that off-label treatment options are not sufficient to manage symptoms in most people with idiopathic hypersomnia....
These findings add much-needed clarity to the experience of people with idiopathic hypersomnia regarding the multiple aspects of this disorder on daily life, and demonstrate a symptom burden that extends far beyond just excessive daytime sleepiness.
Multiple studies have shown that people with idiopathic hypersomnia are impaired on most, or all, health-related QoL (quality of life) domains of the SF-36 (role physical, role emotional, general health perception, vitality, social functioning, mental health, physical function, and bodily pain) compared with national norms even when the majority are treated with wake-promoting agents. Individuals with idiopathic hypersomnia also report significantly worse health-related QoL than healthy controls on the EuroQoL 5-Dimension 5-Level index and the EuroQoL Visual Analog Scale. One study has even reported that people with idiopathic hypersomnia scored significantly lower than people with narcolepsy (type 1, type 2, or either type) on most domains of the Veteran’s RAND 36-item Health Survey, including the social functioning domain”. References: Schneider LD, Stevens J, Husain AM, et al. Symptom severity and treatment satisfaction in patients with idiopathic hypersomnia: the real world idiopathic hypersomnia outcomes study (ARISE). Nat Sci Sleep. 2023;15:89–101. doi:10.2147/NSS.S386021 Trotti LM, Ong JC, Plante DT, Friederich murray C, King R, Bliwise DL. Disease symptomatology and response to treatment in people with idiopathic hypersomnia: initial data from the Hypersomnia Foundation registry. Sleep Med. 2020;75:343–349. doi:10.1016/j.sleep.2020.08.034
Nevsimalova S, Susta M, Prihodova I, Maurovich Horvat E, Milata M, Sonka K. Idiopathic hypersomnia: a homogeneous or heterogeneous disease? Sleep Med. 2021;80:86–91. doi:10.1016/j.sleep.2021.01.031 Ozaki A, Inoue Y, Nakajima T, et al. Health-related quality of life among drug-naive patients with narcolepsy with cataplexy, narcolepsy without cataplexy, and idiopathic hypersomnia without long sleep time. J Clin Sleep Med. 2008;4(6):572–578. doi:10.5664/jcsm.27352
Vernet C, Leu-Semenescu S, Buzare MA, Arnulf I. Subjective symptoms in idiopathic hypersomnia: beyond excessive sleepiness. J Sleep Res. 2010;19(4):525–534. doi:10.1111/j.1365-2869.2010.00824.x Vignatelli L, D’Alessandro R, Mosconi P, et al. Health-related quality of life in Italian patients with narcolepsy: the SF-36 health survey. Sleep Med. 2004;5(5):467–475. doi:10.1016/j.sleep.2004.04.003
Dauvilliers Y, Paquereau J, Bastuji H, Drouot X, Weil JS, Viot-Blanc V. Psychological health in central hypersomnias: the French Harmony study. J Neurol Neurosurg Psychiatry. 2009;80(6):636–641. doi:10.1136/jnnp.2008.161588
Bušková J, Novák T, Miletínová E, et al. Self-reported symptoms and objective measures in idiopathic hypersomnia and hypersomnia associated with psychiatric disorders: a prospective cross-sectional study. J Clin Sleep Med. 2022;18(3):713–720. doi:10.5664/jcsm.9702