DISCOVERY has been made of a safe and effective profile for nerve stimulation treatment in children and adults with mild-to-moderate inflammatory bowel disease (IBD). This New York-based pilot brought forwards encouraging evidence in the first investigation, described by Benjamin Sahn, Cohen Children’s Medical Centre, New York, USA: “To report on the use of non-invasive, transcutaneous vagal nerve stimulation to treat humans with IBD.”
Enrolling patients required diagnosis with IBD at least 3 months before participation, having failed at least one conventional IBD therapy option, and expressing faecal calprotectin (FC) scores of 200 μg/g or above within 4 weeks prior to the study onset. The average age of participants was 14, with ages ranging from 10–21 years, and 55% male. A third of patients were on 5-aminosalicylates, 18% on anti-integrins, and 18% on no medication at all. Ten patients had CD and 12 had UC.
Evaluating these 22 patients with IBD and employing a randomised design, 10 patients received once-daily stimulation with transcutaneous vagal nerve stimulation (ta-VNS) in their left external ear, and 12 a once-daily null stimulation of their left calf for 5 minutes. After 2 weeks, patients crossed over to the alternative treatment for another fortnight, before all patients received ta-VNS at Week 4 for 5 minutes, twice-daily, until Week 12. The primary outcome was ≥50% reduction in FC levels by follow up at Week 16 compared to baseline, which was experienced in 11 of the 17 expressing baseline FC scores >200 μg/g.
Half of all the patients with CD and 43% of the patients with UC achieved clinical remission by Week 16. Sahn expressed his excitement with the results: “There is now a wealth of scientific evidence that the nervous system interacts with the immune system in numerous ways that has a critical impact on disease and health determinants.” He went on to explain the effectiveness of ta-VNS, stating that it “can activate the inflammatory reflex, a neural reflex that modulates innate and adaptive immunity in response to pro-inflammatory mediators.” This pilot study also found improvement in FC and symptoms occurred earlier for patients with UC compared with those with CD.
This investigation, no doubt, reveals promising evidence; however, it requires expansion to a much larger scale before strong conclusions are drawn. Cohen also pointed out a limitation, another area that can be improved by future study, that their results of the ‘sham’ stimulation were not reported on or distinguishable in their data graphs, meaning “that the benefits due to stimulation of the auricular root of the vagus nerve cannot be concluded.”