The conclusion of the study states that acute nVNS treatment is beneficial in reducing pain intensity consistently with a decrease in the use of rescue medication.

Non-invasive vagus nerve stimulation (nVNS) is an effective treatment for migraine patients. It is a flexible, practical and easy to use the technique with reduced risk of drug-drug interactions. These advantages allow the use of nVNS as a complementary treatment option to existing migraine therapies. It also reduces the need for pharmacologic therapies and their associated side effects in the treatment of migraine. The PRESTO trial provided class I evidence for the use of nVNS in patients with episodic migraine. The study demonstrated that nVNS significantly increases the probability of having mild pain or being pain-free 2h post stimulation. nVNS was superior to placebo for the majority of endpoints including pain relief, pain freedom and ≥ 50% responder rates at different time points with the incidence of minimal and mild adverse events.

Rationale behind research:

The present post hoc analysis has been conducted to provide further insight into the practical use of acute nVNS treatment by reporting clinically relevant endpoints that extend beyond the traditional parameters recommended by the International Headache Society (IHS).

Objective:

The present study focused on evaluating the likelihood of experiencing at least a 1-point decrease in pain intensity and assess the efficacy of nVNS when the migraine pain is mild. 

Study outcomes:

• The demographic characteristics were evaluated at baseline

The study outcomes included evaluation of:

• A ≥ 1-point reduction in pain intensity at 30, 60, and 120 min after the first treated attack of the double-blind and open-label periods
• Use of rescue medication use and pain-free rates at 30, 60, and 120 min stratified by initial pain intensity for the first treated attack of both periods

Time Points:  30, 60, and 120 min

Outcomes:

Baseline: There were no significant differences observed at baseline

Study outcomes:

• A significantly higher percentage of patients in acute nCVS group reported a ≥ 1-point decrease in pain intensity at 30 min, 60 min and 120 min after the first attack and all attacks. (Fig 2.)

• There was a higher percentage of patients who did not require rescue medication with nVNS than with sham for the first attack. (Fig 3.)

• The proportion of patients with no pain after treatment was significantly higher with nVNS than with sham at 60 min and 120 min when there was mild pain intensity

The present study indicated clinically essential benefits of nVNS as an acute treatment of migraine. The likelihood that nVNS will reduce pain by at least 1 point and the use of rescue medication highlights its favourable risk-benefit profile. Reduction in the use of pharmacological therapies may encourage patient adherence to nVNS with an opportunity to minimise the potential limitations associated with traditional acute migraine medications including adverse effects, medication overuse and drug-drug interactions. It offered efficacy, flexibility and established safety & tolerability encouraging its earlier use than conventional acute therapies. Pharmacological treatments are demonstrated as beneficial and reserved for severe pain because of issues such as medication-related tolerability and insufficient availability of other acute medications. This analysis establishes the use of nVNS as a practical and useful alternative that can be used frequently and early in an attack to decrease migraine pain, need of rescue medication and drug-related adverse effects.