Understanding Sleep Inertia: A Qualitative Study of the Patient Experience With Idiopathic Hypersomnia

Introduction: Sleep inertia, a core symptom and distinguishing feature of idiopathic hypersomnia, refers to difficulty awakening. This qualitative study generated insights into the experience of sleep inertia and its impact from the patient perspective.

Methods: Concept elicitation interviews were conducted with 20 adults with idiopathic hypersomnia. Interviews included open-ended questions and probes on topics of interest, including sleep inertia. Participants rated (0–10) severity and current bothersomeness for each reported sign/symptom and provided their 3 worst and most bothersome signs/symptoms.

Results: Most participants (n=17, 85%) experienced sleep inertia as a symptom of idiopathic hypersomnia. On average, sleep inertia was rated severe (8.2/10 rating) and highly bothersome (7.4/10 rating). Further, sleep inertia was among the symptoms most commonly identified as 1 of the 3 worst (n=5, 25%) or most bothersome (n=6, 30%). Participants described sleep inertia as extreme difficulty emerging from sleep, commonly accompanied by dysfunction, both cognitive (grogginess, confusion, difficulty focusing and communicating thoughts) and physical (clumsiness). Sleep inertia frequently lasted over 30 minutes (sometimes up to 3 hours), and some participants reported experiencing sleep inertia daily, which interfered with interpersonal relationships, daily functioning, and work performance.

Conclusion: Interviews with patients with idiopathic hypersomnia revealed that sleep inertia is frequent and highly burdensome, with patients experiencing cognitive and physical dysfunction that impacts their social interactions and daily activities, including work. These patient-centric findings demonstrate the complexity, pervasiveness, and impact of sleep inertia in idiopathic hypersomnia and may increase awareness and attention of sleep inertia in clinical practice.