Effects of long-term transcutaneous auricular vagus nerve stimulation on circadian vagal activity in people with Prader-Willi Syndrome: A case-series

• Published in: Research in developmental disabilities 2024-11, Vol.154, p.104855, Article 104855
• Main Authors: Schmausser, Maximilian, Holland, Anthony, Beresford-Webb, Jessica, Eglen, Stephen J., Manning, Katie, Aman, Lucie, Kronhaus, Dina, Koenig, Julian
• Format: Article
• Language: English
• Subjects: Adult; Autonomic Nervous System - physiopathology; Circadian rhythm; Circadian Rhythm - physiology; Emotions - physiology; Female; Heart rate; Heart Rate - physiology; Heart rate variability; Humans; Male; Prader-Willi Syndrome; Prader-Willi Syndrome - physiopathology; Prader-Willi Syndrome - therapy; Transcutaneous auricular vagus nerve stimulation; Transcutaneous Electric Nerve Stimulation - methods; Treatment Outcome; Vagus Nerve - physiology; Vagus Nerve - physiopathology; Vagus Nerve Stimulation - methods; Young Adult
• ISSN: 0891-4222; 1873-3379; 1873-3379
• DOI: 10.1016/j.ridd.2024.104855

Prader-Willi Syndrome (PWS) is a genetic neurodevelopmental disorder marked by disruptions in circadian rhythms and autonomic nervous system (ANS) activity, hyperphagia, and episodes of emotional outbursts. Previous trials suggest that both invasive and non-invasive vagus nerve stimulation (VNS) can reduce emotional outbursts in PWS, potentially through its effects on vagal activity. This case series investigated the effects of transcutaneous auricular VNS (taVNS) on cardiac markers of circadian vagal activity, specifically heart rate variability (HRV) and heart rate (HR), and their potential links to improvements in emotional outbursts. Five individuals with PWS (mean age: 26.9 years; 3 males, 2 females) received four hours of daily taVNS for 12 months, followed by one month of two-hour daily sessions. Outcome measures included daily recording of emotional outbursts and every three months 24-h HRV and HR recordings. Mixed cosinor models were applied to analyze changes in circadian rhythms of HRV and HR. A linear mixed model was used to assess the predictive value of cardiac vagal activity on emotional outbursts. Circadian amplitudes of HRV and HR were significantly higher at the end of the treatment compared to baseline (all p’s < .01). There was a significant increase in the rhythm-adjusted mean of HRV (p < .01), while the rhythm-adjusted HR mean significantly decreased, both indicating increased cardiac vagal activity. Higher rhythm-adjusted mean HRV predicted a lower number of emotional outbursts. The results suggest that taVNS may be effective by targeting ANS activity in individuals with PWS, contributing to improvements in behavioral regulation. •Vagus nerve stimulation resulted in changes in circadian heart rate variability in Prader-Willi Syndrome.•Rhythm-adjusted mean heart rate variability predicted emotional outbursts throughout the trial.•Vagus nerve stimulation may improve behavioral regulation in Prader-Willi Syndrome via autonomic nervous system regulation.