Miglis MG, et al. - In a large online cohort of patients with idiopathic hypersomnia (IH), researchers quantified the symptoms of autonomic nervous system (ANS) dysfunction and ascertained whether the severity of these symptoms interacts with sleepiness, fatigue, and quality of life. Through the website of the Hypersomnia Foundation, a US-based patient advocacy group, 138 IH patients and 81 age- and sex-matched controls were selected. By the study investigators, 24 confirmed IH patients were selected as a comparison group. All candidates finished a battery of online sleep, autonomic, and quality of life questionnaires including the composite autonomic symptom score-31 (COMPASS-31). According to findings, ANS dysfunction symptoms are common in IH. ANS symptom burden was also positively correlated with sleepiness and negatively related to quality of life.