Autonomic Symptom Burden in Idiopathic Hypersomnia (S46.005)

Objective: To assess the symptom severity of autonomic nervous system (ANS) impairment in individuals with idiopathic hypersomnia (IH).

Background: ANS impairment has been reported in other central nervous system hypersomnias, however data on ANS impairment in IH are limited.

Design/Methods: 272 participants with IH and 145 healthy controls completed a battery of online questionnaires including the Composite Autonomic Symptom Score 31 (COMPASS 31), Epworth Sleep Scale (ESS), Morningness-Eveningness Questionnaire (MEQ-SA), Chalder Fatigue Questionnaire (CFQ), Insomnia Severity Index (ISI), RLS single item screen, STOP-Bang Questionnaire, and the RAND 36-Item Health Survey (RAND-36). A descriptive analysis was performed to assess for differences in scores between groups and to assess correlations among individual questionnaires. Because scores were not normally distributed for any measure, median and inter-quartile range are reported, and continuous measures were compared by Wilcoxon rank sum. Participants were identified as cases if they self-reported a formal diagnosis of IH by a physician. All subjects were recruited through the Hypersomnia Foundation website.

Results: Participants with IH reported significantly higher COMPASS 31 scores (30 [25–36] vs. 20 [16.7–23]; p<0.001, d=1.42). IH participants also reported higher ESS scores (16 [13–19] vs. 6 [4–9]; p<0.001, d=2.18) and CFQ scores (30 [26–34] vs. 14 [13–18]; p<0.001, d=2.09). Consistent with these group-wise differences, COMPASS 31 scores showed a strong positive correlation with both ESS (r=0.61, p<0.001) and CFQ (r=0.63, p<0.001) scores.

Conclusions: Symptoms of ANS impairment, sleepiness, and fatigue are more severe in individuals with IH compared to controls. Moreover, ANS symptom burden correlates moderately with higher levels of sleepiness and fatigue. Future analysis will focus on COMPASS subscores and objective autonomic testing to help identify symptomatic domains, with the goal of more focused therapeutic targets for patients with IH.

Disclosure: Dr. Kim has nothing to disclose. Dr. Cheung has nothing to disclose. Dr. Schneider has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Jazz Pharmaceuticals and Hatch Baby. Dr. Schneider holds stock and/or stock options in Knit Health, Inc.. Dr. Trotti has nothing to disclose. Dr. Miglis has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Lundbeck, Schlesinger Associates, Defined Health, Elsevier.