Neuromodulation in trigeminal autonomic cephalalgias: 11-year experience of non-invasive vagus nerve stimulation

Aim To evaluate the effectiveness and tolerability of non-invasive vagus nerve stimulation (nVNS) as acute or preventive treatment, or both, in a cohort of trigeminal autonomic cephalalgia (TAC) patients. Methods A service evaluation retrospectively included patients with TACs between January 2014 and February 2025 who had used, or currently use, nVNS. Data were collected from clinical letters. Data are presented as descriptive statistics analysis and non-parametric tests were performed. Results In total, 108 patients were included, 74 patients with cluster headache (CH), 10 with paroxysmal hemicrania, 15 with hemicrania continua, four with short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT), three with short-lasting unilateral neuralgiform with cranial autonomic symptoms (SUNA) and two with an undifferentiated TAC. Overall, 70 patients considered nVNS useful over a median time using nVNS of 47 (interquartile range = 18–66) months. The median time of use in patients who did not find nVNS useful was 7 (interquartile range = 4–12) months. Twenty-three patients reported an adverse event (AE), while no serious treatment-related AEs occurred. Fifty-nine patients withdrew from using the device, including 11 patients that initially reported nVNS as useful. All groups considered nVNS more useful as preventive, while cluster headache and SUNCT/SUNA patients also considered it useful as acute treatment. Conclusions Our findings complement previous evidence of the effectiveness and tolerability of nVNS in CH in addition to other forms of TACs. Interestingly, nVNS seems to be more effective as preventive rather than as acute treatment in our cohort.