Long-term Effects of Vagus Nerve Stimulation in Treatment-resistant Depression: A 5-year Follow up Case Series

AbstractThis is the first case report of a patient who received long-term (69-month) adjunctive vagus nerve stimulation (VNS) therapy for treatment-resistant depression (TRD) and reached VNS battery end-of-service (EOS).The patient is a 41-year-old female with depression who entered a study of adjunctive VNS therapy for TRD. Her Hamilton Rating Scale for Depression (HAM-D) scores dropped from a mean of 33.5 (pre-implantation baseline period) to 16 at the end of the 12-week acute-phase treatment period, and then fluctuated from <7 (normal range) to scores in the moderately depressed range (∼20) during long-term follow-up. Three and one-half years after VNS implantation, the patient's HAM-D scores began to increase from a score of 18 to a peak score of 27 ∼ 16 months later (5-years post-implantation). The patient subsequently reported that she could no longer feel stimulation from the device and device interrogation 2 weeks later indicated battery EOS. The patient was hospitalized due to worsened depression, the pulse generator was replaced, and medication adjusted. HAM-D scores through the subsequent 9 months of followup returned to a pattern of fluctuations within the range noted during the long-term follow-up period prior to VNS battery EOS.

Download Full-text

Vagus Nerve Stimulation in Treatment-Resistant Depression: Long-term Clinical Outcomes

10.14293/s2199-1006.1.sor-.ppwjmqy.v1 ◽

2021 ◽

Author(s):

Stella Rosson ◽

Nicola Bresolin ◽

Domenico d’Avella ◽

Luca Denaro ◽

Alessandro Landi ◽

...

Keyword(s):

Vagus Nerve ◽

Nerve Stimulation ◽

Vagus Nerve Stimulation ◽

Case Series ◽

University Hospital ◽

Psychiatric Disease ◽

Treatment Resistant Depression ◽

Treatment Resistant ◽

Resistant Depression

I ntroduction Vagus nerve stimulation (VNS) is a neuromodulation technique approved for Treatment-Resistant Depression (TRD).Evidence regarding its long-term efficacy and safety is still scarce. Objectives To descriptively report a case series of 3 patients undergoing adjunctive VNS for TRD with an over 10-year follow-up. Methods We investigated outcomes of clinical interest in patients with ongoing VNS for at least 10 years after the device implantation. They had participated in a larger single-arm interventional study conducted at the University Hospital of Padua. They were diagnosed with chronic unipolar (1), recurrent unipolar (1), and bipolar (1) TRD. Results Our 3 cases had an average 14-year history of psychiatric disease before surgery. Afterward, all subjects achieved clinical remission within two years. 2 patients experienced relapses within the first 4 years of treatment (respectively, 1 and 2 episodes). The other case showed a recurrent trend of brief relapses every two years. Only 1 individual needed to be admitted to the psychiatric unit once. None of them committed suicidal attempts. Prescription of antidepressants remained almost unchanged after the first two years. 2 individuals improved and 1 maintained their working position. Common adverse events were voice alteration (3/3), neck pain (2/3), and cough (2/3). Conclusions Very few cases of 10-year VNS for TRD have been reported so far. For our subjects, VNS was most likely to have a major impact on the clinical course of the disease. This treatment can be a safe and effective adjunctive intervention in a subgroup of patients with TRD.

Download Full-text