Practical and clinical utility of non-invasive vagus nerve stimulation (nVNS) for the acute treatment of migraine: a post hoc analysis of the randomized, sham-controlled, double-blind PRESTO trial

Noninvasive vagus nerve stimulation for migraine: a systematic review and meta-analysis of randomized controlled trials

Background

Medication is commonly used to treat migraine. However, patients may experience adverse events or fail to respond to medication. In recent years, neuromodulation techniques have emerged as potential non-pharmacological therapy for migraine. This article focuses on a systematic review and meta-analysis of randomized controlled trials of non-invasive vagus nerve stimulation (n-VNS) for migraine to determine the efficacy, safety and tolerability of n-VNS.

Methods

We searched PUBMED, EMBASE, and Cochrane Center Register of Controlled Trials databases up to July 15, 2022. Primary outcomes were monthly reduced migraine/headache days, and pain-free rates within 2 h. Secondary outcomes were  ≥ 50% responder rate, headache intensity, monthly acute medication reduction days, and adverse events.

Results

Meta-analysis shows that non-invasive cervical vagus nerve stimulation (n-cVNS) significantly impacted ≥50% responder rate (OR, 1.64; 95% CI, 1.1 to 2.47; p = 0.02), but had no significant effect on reducing migraine days (MD, -0.46; 95% CI, -1.21 to 0.29; p = 0.23) and headache days (MD, -0.68; 95% CI, -1.52 to 0.16; p = 0.11). In contrast, low-frequency non-invasive auricular vagus nerve stimulation (n-aVNS) was found to significantly reduce the number of migraine days (MD, -1.8; 95% CI, -3.34 to -0.26; p = 0.02) and headache intensity (SMD, -0.7; 95% CI, -1.23 to -0.17; p = 0.009), but not the number of acute medication days per month (MD, -1.1; 95% CI, -3.84 to 1.64; p = 0.43). In addition, n-cVNS was found safe and well-tolerated in most patients.

Conclusion

These findings show that n-VNS is a promising method for migraine management.

Vagus nerve stimulation as a novel treatment for systemic lupus erythematous: study protocol for a randomised, parallel-group, sham-controlled investigator-initiated clinical trial, the SLE-VNS study

INTRODUCTION

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease. SLE is treated with immunosuppressants with suboptimal efficacy and high risk of serious side effects. Patients with SLE have increased risk of mortality, organ damage and debilitating treatment-resistant fatigue. Autonomic nervous system dysfunction (AD) is present in approximately half of the patients and may promote autoimmunity by weakening the vagally mediated anti-inflammatory reflex. Recent studies suggest that transcutaneous vagus nerve stimulation (tVNS) has few side effects and beneficial effects on fatigue, pain, disease activity and organ function. This study investigates whether adjuvant tVNS improves measures of fatigue (primary end point), AD, clinical disease activity, inflammation, pain, organ function and quality of life.Hence, this study will contribute to the understanding of AD as a potentially important precursor of fatigue, disease activity, progression and complications in SLE, and how tVNS mechanistically may attenuate this. As adjuvant tVNS use may reduce the need for traditional immunosuppressive therapy, this trial may prompt a shift in the treatment of SLE and potentially other autoimmune disorders.

METHODS AND ANALYSIS

Eighty-four patients with SLE with fatigue and AD will be randomised 1:1 to active or sham tVNS in this double-blinded parallel-group study. In period 1 (1 week), participants will receive a 4 min tVNS 4 times daily and report on fatigue daily. After a 2-week pause, period 2 (8 weeks) will entail tVNS twice daily and participants will report on fatigue, pain and disease activity weekly. Secondary end points will be assessed before and after each period and after 1 week in period 2.

ETHICS AND DISSEMINATION

The study is approved by the Danish Medical Research Ethical Committees (case no: 2120231) and results will be published in international peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT05315739.

Melatonin Moderates the Triangle of Chronic Pain, Sleep Architecture and Immunometabolic Traffic

Preclinical as well as human studies indicate that melatonin is essential for a physiological sleep state, promotes analgesia and is involved in immunometabolic signaling by regulating neuroinflammatory pathways. Experimental and clinical neuromodulation studies for chronic pain treatment suggest that neurostimulation therapies such as spinal cord stimulation, vagus nerve stimulation and dorsal root ganglion stimulation have an impact on circulating inflammatory mediators in blood, cerebrospinal fluid and saliva. Herein, we provide an overview of current literature relevant for the shared pathways of sleep, pain and immunometabolism and elaborate the impact of melatonin on the crossroad of sleep, chronic pain and immunometabolism. Furthermore, we discuss the potential of melatonin as an adjunct to neurostimulation therapies. In this narrative review, we addressed these questions using the following search terms: melatonin, sleep, immunometabolism, obesity, chronic pain, neuromodulation, neurostimulation, neuroinflammation, molecular inflammatory phenotyping. So far, the majority of the published literature is derived from experimental studies and studies specifically assessing these relationships in context to neurostimulation are sparse. Thus, the adjunct potential of melatonin in clinical neurostimulation has not been evaluated under the umbrella of randomized-controlled trials and deserves increased attention as melatonin interacts and shares pathways relevant for noninvasive and invasive neurostimulation therapies.

The Use of Electrical Nerve Stimulation to Treat Migraines: A Systematic Review

Migraines have been defined as an intense unilateral throbbing or pulsating sensation lasting anywhere between a few hours to multiple days. They are the sixth most prevalent disease in the United States, with approximately 18% of women and 6% of men experiencing some form of a migraine throughout their lifetime. In addition, they pose a significant economic burden, accounting for anywhere between $13 and $17 billion in medical costs annually in the United States. While there are a wide variety of treatments for migraines on the market, such as nonsteroidal anti-inflammatory drugs (NSAIDS), beta-blockers, and anti-epileptics, there is still no standard treatment. Moreover, each of these medications has a wide range of side effects, ranging from stomach ulcers to light-headedness. Within the last few decades, the presence of electrical nerve stimulation has emerged as a possible treatment option. These methods are almost free of harmful side effects and may be able to reduce the economic burden on those who suffer from migraines. However, studies have shown mixed results in regard to their efficacy. In this paper, we performed a systematic review to detail the current state of the literature regarding electrical nerve stimulation as a treatment modality for migraines.

Is Noninvasive Vagus Nerve Stimulation a Safe and Effective Alternative to Medication for Acute Migraine Control?

BACKGROUND

Noninvasive neuromodulation devices have been used for a variety of headache disorders, including cluster and migraine, since recently being cleared by the Federal Drug Administration. Although these devices have been touted as low-risk options for improved headache control, the data behind actual efficacy endpoints remain unclear.

OBJECTIVE

To critically assess current evidence regarding the efficacy of the noninvasive vagus nerve stimulator (nVNS) device for acute migraine management.

METHODS

The objective was addressed through the development of a structured critically appraised topic. This included a clinical scenario with a clinical question, literature search strategy, critical appraisal, results, evidence summary, commentary, and bottom line conclusions.Participants included consultant and resident neurologists, a medical librarian, clinical epidemiologists, and a content expert in the field of headache.

RESULTS

A randomized, double-blind, sham-controlled clinical trial was selected for critical appraisal. In this trial, the primary endpoint (pain freedom at 120 min after use of nVNS for first acute migraine attack) was not met when compared with sham device (30.4% for nVNS vs. 19.7% for sham; P=0.067). However, there were statistically significant differences found for various secondary endpoints favoring nVNS, such as pain freedom rates at 30 and 60 minutes, pain relief at 120 minutes, and mean percentage pain score reduction rates at 60 and 120 minutes.

CONCLUSIONS

When comparing nVNS with sham, no statistically significant differences were found with regards to the primary endpoint of pain freedom at 120 minutes, although differences were found with various secondary endpoints and post hoc analysis. nVNS is likely a safe alternative to medications.

Cervical transcutaneous vagal neuromodulation in chronic pancreatitis patients with chronic pain: A randomised sham controlled clinical trial

BACKGROUND & AIMS

Chronic abdominal pain is the primary symptom of chronic pancreatitis, but unfortunately it is difficult to treat. Vagal nerve stimulation studies have provided evidence of anti-nociceptive effect in several chronic pain conditions. We investigated the pain-relieving effects of transcutaneous vagal nerve stimulation in comparison to sham treatment in chronic pancreatitis patients.

METHODS

We conducted a randomised double-blinded, sham-controlled, crossover trial in patients with chronic pancreatitis. Patients were randomly assigned to receive a two-week period of cervical transcutaneous vagal nerve stimulation using the gammaCore device followed by a two-week sham stimulation, or vice versa. We measured clinical and experimental endpoints before and after each treatment. The primary clinical endpoint was pain relief, documented in a pain diary using a visual analogue scale. Secondary clinical endpoints included Patients' Global Impression of Change score, quality of life and Brief Pain Inventory questionnaire. Secondary experimental endpoints included cardiac vagal tone and heart rate.

RESULTS

No differences in pain scores were seen in response to two weeks transcutaneous vagal nerve stimulation as compared to sham treatment (difference in average pain score (visual analogue scale): 0.17, 95%CI (-0.86;1.20), P = 0.7). Similarly, no differences were seen for secondary clinical endpoints, except from an increase in the appetite loss score (13.9, 95%CI (0.5:27.3), P = 0.04). However, improvements in maximum pain scores were seen for transcutaneous vagal nerve stimulation and sham treatments as compared to their respective baselines: vagal nerve stimulation (-1.3±1.7, 95%CI (-2.21:-0.42), P = 0.007), sham (-1.3±1.9, 95%CI (-2.28:-0.25), P = 0.018). Finally, heart rate was decreased after two weeks transcutaneous vagal nerve stimulation in comparison to sham treatment (-3.7 beats/min, 95%CI (-6.7:-0.6), P = 0.02).

CONCLUSION

In this sham-controlled crossover study, we found no evidence that two weeks transcutaneous vagal nerve stimulation induces pain relief in patients with chronic pancreatitis.

TRIAL REGISTRATION NUMBER

The study is registered at NCT03357029; www.clinicaltrials.gov.

Noninvasive Neuromodulation in Migraine

PURPOSE OF REVIEW

The past two decades has seen an influx of noninvasive neuromodulation devices aimed at treatment of various primary headache disorders, including cluster headache and migraine. This narrative review is to summarize the current options in noninvasive neuromodulation in migraine.

RECENT FINDINGS

A variety of noninvasive neuromodulation devices have been FDA cleared and marketed for use in migraine, including single-pulse transcranial magnetic stimulation (sTMS), noninvasive vagal nerve stimulators (nVNS), and external trigeminal nerve stimulators (eTNS). Newer devices include peripheral electrical stimulation devices (PES), caloric stimulation, and others. Each has varying levels of evidence supporting its use in migraine, tolerability profiles, and access issues. Noninvasive neuromodulation devices can be beneficial when used in patients with migraine, with minimal side effects. As more devices are developed, approved, and marketed in the future, rigorous research on efficacy and safety remain a top priority.

Review of Abdominal Migraine in Children

Abdominal migraine is a type of functional abdominal pain disorder that affects 0.2% to 4.1% of children. It consists of paroxysmal, recurrent, and acute abdominal pain attacks with associated symptoms, including pallor, nausea, vomiting, anorexia, headache, and photophobia. In between episodes, patients return to their baseline health. Abdominal migraine is a clinical diagnosis. Its diagnostic criteria are outlined under the Rome IV criteria and the International Classification of Headache Disorders III criteria. Hypothesized contributors to its pathophysiology include a combination of visceral hypersensitivity, gut-brain enteric nervous system alterations, and psychological factors. Treatment is focused on preventive measures and mostly includes nonpharmacologic approaches. Possible pharmacologic treatments include abortive medications used for migraine headaches such as analgesics and antiemetics. Abdominal migraine is likely underdiagnosed and is poorly understood. Individuals who have abdominal migraine report a lower quality of life, rendering it an important diagnosis. The aim of this article is to review the epidemiology, clinical presentation, pathophysiology, diagnosis, and treatment of abdominal migraine in children.

Update on noninvasive neuromodulation for migraine treatment-Vagus nerve stimulation

Noninvasive neurostimulation methods are particularly suited for migraine treatment thanks to their most favorable adverse event profile. Among them, noninvasive vagus nerve stimulation (nVNS) has raised great hope because of the role the vagus nerve is known to play in pain modulation, inflammation and brain excitability. We will critically review the clinical studies performed for migraine attack treatment and migraine prevention with the GammaCore® device, which allows cervical vagus nerve stimulation. nVNS is effective for the abortive treatment of migraine attacks, although the effect size is modest and numbers-to-treat appear not superior to those of other noninvasive neurostimulation methods, and inferior to those of oral triptans. The effect of nVNS with the GammaCore® in migraine prevention is not superior to sham stimulation, except possibly in patients with high adherence to the treatment. Both in acute and preventive trials, nVNS was characterized by an outstanding tolerance and safety profile, like the other noninvasive neurostimulation techniques. In physiological animal and human studies, cervical nVNS was shown to generate somatosensory evoked responses, to modulate pain perception and several areas of the cerebral pain network, and to inhibit experimental cortical spreading depression, which are relevant effects for migraine therapy.

Study protocol for a randomised double-blinded, sham-controlled, prospective, cross-over clinical trial of vagal neuromodulation for pain treatment in patients with chronic pancreatitis

INTRODUCTION

The management of chronic pancreatitis (CP) is challenging and requires a personalised approach focused on the individual patient's main symptoms. Abdominal pain is the most prominent symptom in CP, where central pain mechanisms, including sensitisation and impaired pain modulation, often are involved. Recent clinical studies suggest that vagal nerve stimulation (VNS) induces analgesic effects through the modulation of central pain pathways. This study aims to investigate the effect of 2 weeks transcutaneous VNS (t-VNS) on clinical pain in patients with CP, in comparison to the effect of sham treatment.

METHODS AND ANALYSIS

Twenty-one patients with CP will be enrolled in this randomised, double-blinded, single-centre, sham-controlled, cross-over study. The study has two treatment periods: A 2-week active t-VNS using GammaCore device and a 2-week treatment with a sham device. During both treatment periods, the patients are instructed to self-administer VNS bilaterally to the cervical vagal area, three times per day. Treatment periods will be separated by 2 weeks. During the study period, patients will record their daily pain experience in a diary (primary clinical endpoint). In addition, all subjects will undergo testing which will include MRI, quantitative sensory testing, cardiac vagal tone assessment and collecting blood samples, before and after the two treatments to investigate mechanisms underlying VNS effects. The data will be analysed using the principle of intention to treat.

ETHICS AND DISSEMINATION

The regional ethics committee has approved the study: N-20170023. Results of the trial will be submitted for publication in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

The study is registered at www.clinicaltrials.gov: NCT03357029.

Noninvasive peripheral vagal nerve stimulation prevents migraine aura: A case report

We describe a patient affected by migraine with visual and somatosensory aura, whose symptoms were consistently attenuated by noninvasive peripheral vagal nerve stimulation (nVNS) in multiple prospectively recorded attacks. When compared with the current standard of care, nVNS significantly reduced the duration of visual aura in all the attacks ( n = 5) and prevented the somatosensory aura in three of the five attacks. The overall duration of nVNS-treated auras was 19.0 ± 4.2 min, significantly shorter than the duration of aura in attacks treated with standard of care (103.8 ± 10.3 min). This single-case study requires confirmation in a larger sample size, but we believe that this first report is suggestive of likely efficacy given the relatively high number of treated attacks and the consistent effect of nVNS.

Targeted Vagus Nerve Stimulation for Rehabilitation After Stroke

Stroke is a leading cause of disability worldwide, and in approximately 60% of individuals, upper limb deficits persist 6 months after stroke. These deficits adversely affect the functional use of the upper limb and restrict participation in day to day activities. An important goal of stroke rehabilitation is to improve the quality of life by enhancing functional independence and participation in activities. Since upper limb deficits are one of the best predictors of quality of life after stroke, effective interventions targeting these deficits may represent a means to improve quality of life. An increased understanding of the neurobiological processes underlying stroke recovery has led to the development of targeted approaches to improve motor deficits. One such targeted strategy uses brief bursts of Vagus Nerve Stimulation (VNS) paired with rehabilitation to enhance plasticity and support recovery of upper limb function after chronic stroke. Stimulation of the vagus nerve triggers release of plasticity promoting neuromodulators, such as acetylcholine and norepinephrine, throughout the cortex. Timed engagement of neuromodulators concurrent with motor training drives task-specific plasticity in the motor cortex to improve function and provides the basis for paired VNS therapy. A number of studies in preclinical models of ischemic stroke demonstrated that VNS paired with rehabilitative training significantly improved the recovery of forelimb motor function compared to rehabilitative training without VNS. The improvements were associated with synaptic reorganization of cortical motor networks and recruitment of residual motor neurons controlling the impaired forelimb, demonstrating the putative neurobiological mechanisms underlying recovery of motor function. These preclinical studies provided the basis for conducting two multi-site, randomized controlled pilot trials in individuals with moderate to severe upper limb weakness after chronic ischemic stroke. In both studies, VNS paired with rehabilitation improved motor deficits compared to rehabilitation alone. The trials provided support for a 120-patient pivotal study designed to evaluate the efficacy of paired VNS therapy in individuals with chronic ischemic stroke. This manuscript will discuss the neurobiological rationale for VNS therapy, provide an in-depth discussion of both animal and human studies of VNS therapy for stroke, and outline the challenges and opportunities for the future use of VNS therapy.

Saliva molecular inflammatory profiling in female migraine patients responsive to adjunctive cervical non-invasive vagus nerve stimulation: the MOXY Study

Background

Rising evidence indicate that oxytocin and IL-1β impact trigemino-nociceptive signaling. Current perspectives on migraine physiopathology emphasize a cytokine bias towards a pro-inflammatory status. The anti-nociceptive impact of oxytocin has been reported in preclinical and human trials. Cervical non-invasive vagus nerve stimulation (nVNS) emerges as an add-on treatment for the preventive and abortive use in migraine. Less is known about its potential to modulate saliva inflammatory signaling in migraine patients. The rationale was to perform inter-ictal saliva measures of oxytocin and IL-1ß along with headache assessment in migraine patients with 10 weeks adjunctive nVNS compared to healthy controls.

Methods

12 migraineurs and 12 suitably matched healthy control were studied with inter-ictal saliva assay of pro- and anti-neuroinflammatory cytokines using enzyme-linked immuno assay techniques along with assessment of headache severity/frequency and associated functional capacity at baseline and after 10 weeks adjunctive cervical nVNS.

Results

nVNS significantly reduced headache severity (VAS), frequency (headache days and total number of attacks) and significantly improved sleep quality compared to baseline (p < 0.01). Inter-ictal saliva oxytocin and IL-1β were significantly elevated pre- as well as post-nVNS compared to healthy controls (p < 0.01) and similarly showed changes that may reflect the observed clinical effects.

Conclusions

Our results add to accumulating evidence for a therapeutic efficacy of adjunct cervical non-invasive vagus nerve stimulation in migraine patients. This study failed to provide an evidence-derived conclusion addressed to the predictive value and usefulness of saliva assays due to its uncontrolled study design. However, saliva screening of mediators associated with trigemino-nociceptive traffic represents a novel approach, thus deserve future targeted headache research.

Trial registration This study was indexed at the German Register for Clinical Trials (DRKS No. 00011089) registered on 21.09.2016

Consistent effects of non-invasive vagus nerve stimulation (nVNS) for the acute treatment of migraine: additional findings from the randomized, sham-controlled, double-blind PRESTO trial

Background

Non-invasive vagus nerve stimulation (nVNS) has been shown to be practical, safe, and well tolerated for treating primary headache disorders. The recent multicenter, randomized, double-blind, sham-controlled PRESTO trial provided Class I evidence that for patients with episodic migraine, nVNS significantly increases the probability of having mild pain or being pain-free 2 h post stimulation. We report additional pre-defined secondary and other end points from PRESTO that demonstrate the consistency and durability of nVNS efficacy across a broad range of outcomes.

Methods

After a 4-week observation period, 248 patients with episodic migraine with/without aura were randomly assigned to acute treatment of migraine attacks with nVNS (n = 122) or a sham device (n = 126) during a double-blind period lasting 4 weeks (or until the patient had treated 5 attacks). All patients received nVNS therapy during the subsequent 4-week/5-attack open-label period.

Results

The intent-to-treat population consisted of 243 patients. The nVNS group (n = 120) had a significantly greater percentage of attacks treated during the double-blind period that were pain-free at 60 (P = 0.005) and 120 min (P = 0.026) than the sham group (n = 123) did. Similar results were seen for attacks with pain relief at 60 (P = 0.025) and 120 min (P = 0.018). For the first attack and all attacks, the nVNS group had significantly greater decreases (vs sham) in pain score from baseline to 60 min (P = 0.029); the decrease was also significantly greater for nVNS at 120 min for the first attack (P = 0.011). Results during the open-label period were consistent with those of the nVNS group during the double-blind period. The incidence of adverse events (AEs) and adverse device effects was low across all study periods, and no serious AEs occurred.

Conclusions

These results further demonstrate that nVNS is an effective and reliable acute treatment for multiple migraine attacks, which can be used safely while preserving the patient’s option to use traditional acute medications as rescue therapy, possibly decreasing the risk of medication overuse. Together with its practicality and optimal tolerability profile, these findings suggest nVNS has value as a front-line option for acute treatment of migraine.

Trial registration

ClinicalTrials.gov identifier: NCT02686034.