Study objectives: RBD may result in sleep related injury (SRI) particularly if a patient exits the bed during dream enactment behavior (DEB). The complex auditory processing and low arousal threshold of REM sleep offers a therapeutic window to halt behavior prior to SRI. We evaluated whether a recorded message prevents SRI in medically refractory RBD.
Design: Case Series.
Setting: Sleep disorders center.
Patients: Four consecutive RBD patients with continued SRI despite both clonazepam and melatonin therapy.
Intervention: A pressurized bed alarm customized with a familiar voice to deliver a calming message during vigorous DEB.
Measurements and results: The RBDQ-HK evaluated RBD symptoms, and SRI was further quantified with a new clinical tool, the Minnesota Parasomnia Injury Scale. All patients reported a decrease in RBD symptoms and SRI. No injuries occurred post-intervention. Pre-treatment: 5 serious events (SE), 80 minor events (ME), and 193 near events (NE) were noted over 66 patient-months (4.21 events/pt-mo). Post-treatment: 0 SE, 0 ME, and 3 NE were noted after a follow up period of 63 pt-months (0.05 event/pt-mo). There were 176 total bed alarm interventions (2.79 interventions/pt-mo). No adverse effects were reported, and all 4 patients described a minimal burden of treatment. RBD symptoms improved as the average RBDQ-HK score decreased from 68 (range: 53-80) to 54 (range 42-65).
Conclusion: A customized bed alarm may be an effective method to prevent SRI in RBD. This intervention is most suitable for cases of medically refractory RBD and/or for those patients who are unable to tolerate medical therapy.
Keywords: Minnesota Parasomnia Injury Scale; Parkinson disease; REM sleep behavior disorder; bed alarm; clonazepam; melatonin.