Investigating sleep microarchitecture to better understand idiopathic hypersomnia pathophysiology and phenotype heterogeneity
2020 Strategic Research Grant
Nadia Gosselin, PhD
Université de Montréal
Key Project Outcome
This research aimed to deepen our understanding of hypersomnolence disorders, particularly idiopathic hypersomnia. The initial objectives were to investigate how sleep patterns at different scales—ranging from overall sleep stages (macro-architecture) to specific neural activities (micro-architecture) —relate to excessive daytime sleepiness and unrefreshing sleep in central disorders of hypersomnolence (CDH), with our focus being idiopathic hypersomnia. Additional objectives were explored, such as sleep misperception and its clinical implications in people with CDH.
The analysis of macro-architecture revealed that patients with idiopathic hypersomnia have a relatively good sleep quality when compared to good sleepers. However, when we performed advanced analysis of their sleep, we observed that patients with idiopathic hypersomnia have changes in their brain activity particularly during the deep sleep. Moreover, more important changes in brain activity were associated with more severe excessive daytime sleepiness. This suggests that sleep homeostasis (balance between the sleep that is needed and the sleep that is provided) is disrupted, which could underlie the unrefreshing nature of sleep in hypersomnolence. These results highlight how measuring sleep at different levels can contribute to the understanding of the excessive daytime sleepiness.
The study also explored total sleep time misperception in idiopathic hypersomnia patients compared to patients with narcolepsy and good sleepers. We observed that idiopathic hypersomnia patients underestimate their sleep duration compared to the actual duration measured with objective polysomnographic measures. This discrepancy was most pronounced in narcolepsy type 1 and idiopathic hypersomnia. Such findings underscore the importance of considering the patients’ self-reported sleep experiences alongside objective data in both diagnosis and treatment.
The research highlights the complexity of hypersomnolence disorders and the need for advanced tools to capture subtle sleep processes. By integrating macro- and micro-architectural analyses with patients self-reported, subjective experiences, this work provides a robust framework for improving diagnostic accuracy and developing more targeted interventions for CDH. These findings advance both scientific knowledge and clinical care in the field of sleep medicine and open the door to more personalized care.
Journal Articles
Journal of Sleep Research
Sleep architecture in idiopathic hypersomia
Sleep state misperception in central disorders of hypersomnolence
Unrefreshing naps and sleep architecture during the multiple sleep latency test in idiopathic hypersomia
Scientific Reports
Sleep architecture in idiopathic hypersomia: the influence of age, sex, and body mass index
SLEEP
Abnormal sleep slow wave morphology in idiopathic hypersomia
Sleep state misperception in central disorders of hypersomnolence
Are unrefreshing naps associated with nocturnal sleep architecture specificities in idiopathic hypersomnia?