gms | German Medical Science

Objective: Over the last years, it has been shown that vagal-nerve-stimulation (VNS) is not only a sufficient tool in the treatment of epilepsy, but also has beneficial effects on patients with depressive disorders. It remains unclear, whether different subtypes of depressive disorders as a comorbidity of epilepsy respond to VNS in the same manner.

Methods: In a prospective clinical trial, we investigated four different subtypes of depressive disorders as a comorbidity of epilepsy: interictal dysphoric disorder (IDD), major depression (MD), personality disorder cluster (PDC) and organic personality disorder (OPD). 64 patients with epilepsy and a history of different types of depressive symptoms (26 IDD, 16 MD, 16 PDC, 6 OPD) were treated with VNS. The diagnosis was established by an independent psychiatrist, who performed Montgomery–Åsberg Depression Rating Scale (MADRS) and Beck-Depressions-Inventar (BDI) before andafterVNS-surgery.

Results: Depressive symptoms ameliorated in response to VNS. The MADRS score improved from a mean of 29 to 18 and the BDI score showed a reduction from 23 to 14 in the overall of all patients. All subtypes of depressive disorders improved from VNS as well. 56% of IDD patients had a reduction of depressive symptoms. The symptoms of 87% of patients with MD ameliorated. Half of the PDC patients showed a positive response towards VNS and 66% of patients with OPD improved.

Conclusion: Our data show a beneficial effect of VNS in patients with depressive disorders as a comorbidity of difficult-to-treat epilepsy. Moreover, we were able to show the response of different subtypes of depressive symptoms to VNS. Especially interictal dysphoric disorder as the most common comorbidity and nearly all patients with major depression improved. Against this backdrop, one could argue VNS should have a more crucial position in the treatment of difficult-to-treat epilepsy, especially in terms of comorbidity with depressive symptoms.