Isolated REM sleep behaviour disorder in the Tasmanian ISLAND Sleep Study: prevalence and profiles of prodromal dementia

Abstract

AbstractBackgroundIdentifying people with isolated REM sleep behaviour disorder (iRBD) provides important opportunities for targeted dementia prevention as iRBD is a prodrome of Lewy Body dementia (LBD) and other neurodegenerative diseases (NDD). There have been no prevalence studies of iRBD in Australia and little is known about whether associated motor, cognitive, olfactory and circadian features influence the progression to different NDD. The Island Study Linking Ageing and Neurodegenerative Disease (ISLAND) Sleep Study aims to identify the iRBD prevalence in Tasmania and determine how different iRBD profiles predict progression to dementia and other NDD.MethodAdults aged 50+ years in Tasmania completed online questionnaires including the REM Sleep Behaviour Disorder Screening Questionnaire (RBDSQ), RBD single question screen (RBD1Q), Pittsburgh Sleep Quality Index (PSQI), and questions regarding dreaming, autonomic, motor s, and pain symptoms.Result2,905 participants have been recruited (mean (SD) age 64 (7.7) years; 26% male). 273 (9.4%) have ‘probable’ iRBD (pRBD) based on the RBDQ1. Compared to those without pRBD, the pRBD group have poorer sleep quality (66% vs 57%), greater autonomic dysfunction (median score 18 vs 13), more pain (particularly stabbing and itching pain), higher risk for sleep apnoea (30% vs 13%), more intense dreams (21% vs 8%), and more motor symptoms, including shaky limbs (16% vs 6%) and slurred speech (12% vs 6%).Conclusion2905 participants have been recruited (mean (SD) age 64 (7.7) years; 26% male). 273 (9.4%) have ‘probable’ iRBD (pRBD) based on the RBDQ1. Compared to those without pRBD, the pRBD group have poorer sleep quality (66% vs 57%), greater autonomic dysfunction (median score 18 vs 13), more pain (particularly stabbing and itching pain), higher risk for sleep apnoea (30% vs 13%), more intense dreams (21% vs 8%), and more motor symptoms, including shaky limbs (16% vs 6%) and slurred speech (12% vs 6%).