Repeated electrical vestibular nerve stimulation (VeNS) reduces severity in moderate to severe insomnia; a randomised, sham-controlled trial; the modius sleep study

Background: Insomnia is a prevalent health concern in the general population associated with a range of adverse health effects. New, effective, safe and low-cost treatments, suitable for long-term use, are urgently required. Previous studies have shown the potential of electrical vestibular nerve stimulation (VeNS) in improving insomnia symptoms, however only one sham-controlled trial has been conducted on people with chronic insomnia. Objectives: /Hypothesis: Repeated VeNS delivered by the Modius Sleep device prior to sleep onset will show superior improvement in Insomnia Severity Index (ISI) scores over a 4-week period compared to sham stimulation. Methods: In this double-blinded, multi-site, randomised, sham-controlled study, 147 participants with moderate to severe insomnia (ISI≥15) were recruited and allocated a VeNS or a sham device (1:1 ratio) which they were asked to use at home for 30 min daily (minimum 5 days per week) for 4 weeks. Results: After 4 weeks, mean ISI score reduction was 2.26 greater in the VeNS treatment group than the sham group (p = 0.002). In the per protocol analysis, the treatment group had a mean ISI score decrease of 5.8 (95 % CI [-6.8, −4.81], approaching the clinically meaningful threshold of a 6-point reduction, with over half achieving a clinically significant decrease. Furthermore, the treatment group showed superior improvement to the sham group in the SF-36 (Quality of Life) energy/fatigue component (PP p = 0.004, effect size 0.26; ITT p = 0.006, effect size 0.22). Conclusions: Modius sleep has the potential to provide a viable, non-invasive and safe clinically meaningful alternative treatment option for insomnia.