0703 The burden of obstructive sleep apnoea and periodic limb movements during sleep on symptoms of parasomnia

Abstract Introduction Both obstructive sleep apnoea (OSA) and periodic limb movements during sleep (PLMS) may trigger arousals which could induce parasomnias. However, the burden of OSA and PLMS in parasomnia is not fully understood. The aim of the study was to understand the prevalence of OSA and PLMS and their association with symptoms of parasomnia in patients referred with parasomnia for an inpatient polysomnography (PSG). Methods In this retrospective project we analysed demographics, medical history and PSG data of 94 patients with parasomnia. The relationship between symptoms of parasomnia, OSA and PLMS were analysed with logistic regression analyses. Data are expressed as odds ratio /95% confidence intervals/. Results Forty-seven patients were diagnosed with OSA and 19 with PLMS. Parasomnia symptoms consisted dream enactment (n=28), abnormal movements (n=35), sleep talking (n=36), confusional arousals (n=27), sleep walking (n=36), night terrors (n=18), nightmares (n=15), sleep eating (n=8) and sexsomnia (n=2). Based on symptoms and PSG results, 45 were diagnosed with REM-parasomnia, 63 with non-REM parasomnia, 14 had overlap (both REM and non-REM parasomnia). Interestingly, non-REM parasomnias were inversely related to both OSA (-0.89 /-1.77-0.00/) and PLMS (-1.60 /-2,69- -0.55/, p< 0.01). More particularly, OSA was less prevalent in patients with night terrors (-1.52 /-2.72- -0.32, p< 0.01), whilst PLMS was more prevalent in patients with dream enactment (1.26 /0.21-2.30/, p=0.03), but was less prevalent in patients with nightmares (-2.30 /-5.164-0.56/, p=0.03), and with sleep walking (-1.96 /-3.49- -0.42/, p< 0.01). Conclusion Both OSA and PLMS are prevalent in patients with parasomnia, however their association with specific diseases and symptoms is less evident. Further studies are necessary to understand if they could be treatable traits in parasomnias. Support (if any)