0690 A Conceptual Disease Model of the Symptoms and Impacts of Narcolepsy Type 2 from the Patient Perspective

Abstract Introduction Narcolepsy type 2 (NT2) is characterized by excessive daytime sleepiness (EDS) alongside other diagnostically relevant symptoms, including disrupted nighttime sleep, sleep paralysis, and hypnagogic/hypnopompic hallucinations. This qualitative study amplifies the voices of patients to identify the most bothersome and meaningful symptoms and impacts of NT2. Methods Participants were recruited through a third-party recruitment vendor, patient advocacy groups, and a patient conference. Twenty adults diagnosed with NT2 completed concept-elicitation interviews discussing their experience with NT2. Interviews included open-ended questions and probes on topics informed by a targeted literature review. Participants rated bothersomeness (0–10) for current symptoms and impacts and reported their 3 most bothersome symptoms. Concept frequencies and bothersomeness ratings were used to evaluate salience (ie, reported by ≥50% of participants and average bothersomeness rating ≥5) and develop a conceptual disease model. Results Participants identified 30 symptoms and 38 impacts of NT2; 17 symptoms and 13 impacts were deemed salient. The most frequently reported salient symptoms included chronic daytime sleepiness (100%; mean SD bothersomeness: 8.6 1.6), brain fog (95%; 8.3 1.5), memory problems (90%; 7.5 1.6), fatigue (90%; 8.2 1.7), excessive napping (85%; 6.3 2.8), unintentional daytime sleep episodes (85%; 8.5 2.1), difficulty concentrating (80%; 8.2 1.5), and sleep inertia (80%; 7.8 1.8). Chronic daytime sleepiness, fatigue, and brain fog were most frequently mentioned among the 3 most bothersome symptoms. Salient impacts included difficulties with instrumental activities of daily living (100%; mean SD bothersomeness: 6.7 2.7), work (90%; 8.2 2.1), planning social activities (85%; 6.7 1.9), recreational activities (65%; 6.4 1.9), and school (50%; 9.0 1.7), as well as stress (70%; 6.2 1.7) and negative impacts on relationships (80%; 6.5 2.4) and mobility (50%; 6.5 1.5). Conclusion The lived experience of NT2 is defined not only by EDS but also by fatigue, sleep inertia, and cognitive difficulties. Further, NT2 has a substantial impact on daily functioning and quality of life. A conceptual disease model was developed to offer a structured representation of the lived experiences of patients with NT2, providing a critical framework for understanding patient perspectives and guiding future research and interventions. Support (if any) Jazz Pharmaceuticals