US-based adults with IH completed a virtual survey comprising multiple patient-reported outcome measures. Symptom severity and treatment satisfaction were assessed using the Idiopathic Hypersomnia Severity Scale (IHSS), Epworth Sleepiness Scale (ESS), and Treatment Satisfaction Questionnaire for Medication, version II (TSQM-vII). Participants’ quality of life and functional impairment are reported separately.

Seventy-five participants were enrolled (mean±SD age, 34.1±10.7 years; 81.3% female; mean±SD 24-hour sleep duration, 11.6±3.4 hours); psychiatric comorbidities were reported by 44.0% (most commonly anxiety disorders [34.7%]). Most participants (89.3%) used off-label medications (stimulants [61.3%], wake-promoting agents [28.0%], antidepressants [18.7%], stimulants+antidepressants [14.7%]) and/or other measures to manage IH symptoms (93.3%, most frequently caffeine [73.3%]). Mean±SD IHSS scores were 35.2±7.6, with 95.9% of participants scoring ≥22 (cutoff separating untreated IH from controls). Mean±SD ESS scores were 14.5±3.5, with 88.0% of participants scoring ≥11 (indicating pathologic sleepiness). Participants’ mean±SD TSQM-vII global satisfaction score (0–100 scale) was 61.9±21.2, suggesting low satisfaction with treatment. The most-difficult-to-treat symptoms reported were EDS (53.3%), brain fog (17.3%), and sleep inertia (13.3%).

The ARISE study results indicate that IH symptom severity measures were high despite long-term use of off-label medications and behavioral measures to treat IH symptoms. Participants had low satisfaction with current IH treatments, suggesting that therapies with demonstrated efficacy, including pharmacologic and behavioral, are needed.