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Background Vagus nerve stimulation (VNS) is an effective neuromodulatory treatment option for patients with surgically inoperable, pharmacoresistant epilepsy. This study aims to assess the clinical efficacy of VNS neuromodulation, and attempts to identify patient demographic/factors which may suggest a more favourable response to VNS therapy.Methods This study includes 23 patients in Central Adelaide Health Network, who underwent VNS insertion with at least 12 months of VNS titration. The primary outcome was seizure frequency reduction at 6 and 12 months. Other data points were collected, including baseline cohort characteristics, underlying epilepsy classification and pathology, VNS settings, and history of antiseizure medications. Data was collected through electronic medical records (EMR), and retrospectively analysed.Results Prior to VNS insertion, the average seizure frequency within the cohort was 66 per month. At 6 months follow-up, the average seizure frequency decreased to 44 per month (p-value 0.013). At 12 months, the average seizure frequency was 42 per month. A multivariable regression demonstrated no linear correlation demonstrated between age, age of epilepsy onset, age at VNS insertion, duration of epilepsy diagnosis at VNS insertion, number of AEDs prior to VNS, total number of AEDs trialled, baseline seizure frequency, and response rate (%) at 12 months. The corresponding p-values also suggest that there is no statistically significant relationship observed.Conclusion VNS treatment remains a potentially effective treatment option in severe drug-refractory epilepsy. Although no patient characteristics investigated had a linear relationship with response rate, this may suggest that VNS therapy should be considered in drug-refractory epilepsy regardless of demographics.