A first of its kind trial has shown transcutaneous auricular vagus nerve stimulation improves symptoms of erythematotelangiectatic rosacea, raising the prospect of a new cost-effective therapeutic option for patients.
A team of Chinese researchers randomised 72 patients with rosacea to receive either transcutaneous auricular vagus nerve stimulation (taVNS) pulses at 30 Hz with a pulse width of 200 μs for 30 minutes per day, or a sham stimulation, for three weeks.
After three weeks, the patients in the stimulation group had a lower mean Clinician’s Erythema Assessment (CEA) score compared with the group who received sham stimulation (at 1.56 vs 2.47).
Patients who received vagus nerve stimulation also showed reduced signs of anxiety and depression after treatment, as measured by the GAD-7, PHQ-9, and FSS-9 instruments.
Improvement in symptoms continued through the treatment-free follow-up period. At 27 weeks, the stimulation group had a lower mean CEA score, Patient Self-Assessment (PSA) and Global Flushing Severity Scale score than those who received sham stimulation.
Two patients in the treatment group and three in the sham stimulation group reported adverse events, including urticaria and tinnitus, but these were mild and resolved within 1-5 days.
“In conjunction with durable post-treatment effects and noninvasive characteristics, this modality is particularly advantageous for special populations (such as pregnant people) who are contraindicated for standard therapies,” the authors wrote in JAMA Dermatology [link here].
Treatment could address disease relapse
The data supported the findings of a pilot study from this research team.
“TaVNS achieves multisystem therapeutic effects by synergistically modulating the cholinergic anti-inflammatory reflex and rebalancing cytokine networks, with targeted suppression of pathogenic cytokines being elicited, including interleukin (IL)–1β, IL-6, high mobility group box–1, and tumor necrosis factor (TNF)–α,” the investigators wrote.
“Accumulating evidence has revealed that the pathogenesis of rosacea involves the dysregulation of multiple inflammatory signaling pathways, cytokine networks, and immune cell responses.”
They said the latest results added weight to the group’s prior findings and suggested vagus nerve stimulation delivered a systemic therapeutic benefit which was different to localised treatments like brimonidine or botulinum toxin.
“This systemic effect aligns with the role of the vagus nerve as a master regulator of the inflammatory reflex and reinforces the hypothesis that rosacea (particularly the erythematotelangiectatic subtype) may represent a systemic disorder that originates due to dysregulated neuroimmune interactions,” the authors noted.
While study was the first randomised, double-blind sham controlled study looking at this treatment in rosacea patients, it was a single centre trial with a small sample size.
The trial only recruited patients with “standard” rosacea, and further trials were needed to validate the findings in patients with refractory disease.
Despite these limitations, the data suggested the treatment was associated with sustained remission of disease. This was an important factor given rosacea’s high relapse propensity.
“These results position taVNS as a novel and cost-effective therapeutic option for [erythematotelangiectatic rosacea] management,” the authors said.