RESUMO
Depression is the leading cause of disability worldwide, and it is related to high suicide rates. Furthermore, a great number of patients do not respond to any of the available treatments. Deep brain stimulation (DBS), a versatile technology with expanding indications, is considered a potential treatment for resistant depression. However, in over 10 years of clinical research, its efficacy has not been completely proven. Although new trials using DBS for treatment-resistant depression keep emerging, two of the three Level I evidence-based studies recently conducted have not provided conclusive data. Methodological limitations andmajor biases have compromised the obtention of clearer results. In this systematic review of the literature, we intend to critically assess the clinical trials performed in this field.
Assuntos
Estimulação Encefálica Profunda/efeitos adversos , Estimulação Encefálica Profunda/história , Estimulação Encefálica Profunda/instrumentação , Estimulação Encefálica Profunda/métodos , Transtorno Depressivo Resistente a Tratamento/terapiaRESUMO
OBJECTIVE: Stimulation of the inferior thalamic peduncle (ITP) is emerging as a promising new therapeutic target in certain psychiatric disorders. The circuitry that includes the nonspecific thalamic system (NSTS), which projects via the ITP to the orbitofrontal cortex (OFC), is involved in the physiopathology of major depression disorder (MDD) and obsessive compulsive disorder (OCD). The safety and efficacy of chronic ITP stimulation in cases of MDD and OCD refractory to medical treatment is presented. MATERIALS AND METHODS: Six patients with OCD and one with MDD were implanted with tetrapolar deep brain stimulation electrodes in the ITP (x = 3.5 mm lateral to the ventricular wall, y = 5 mm behind the anterior commissure, and z = at the intercommissural plane, i.e., anterior commissure-posterior commissure [AC-PC] level). The effect of chronic stimulation at 130 Hz, 450 µs, and 5.0 V on OCD was evaluated before and 3, 6, and 12 months after initiation of electrical stimulation through the Yale-Brown Obsessive Compulsive Scale, Hamilton Depression Rating Scale, and Global Assessment of Function scale. RESULTS: Chronic ITP electrical stimulation in OCD patients decreased the mean Yale-Brown Obsessive Compulsive Scale score to around 51% for the group at the 12-month follow-up, and increased the mean Global Assessment of Function scale score to 68% for a significant improvement (P = 0.026). Three of 6 patients returned to work. The Hamilton Depression Rating Scale score of the only patient with MDD treated to date went from 42 to 6. This condition of the patient, who had been incapacitated for 5 years prior to surgery, has not relapsed for 9 years. Three OCD patients with drug addiction continued to consume drugs in spite of their improvement in OCD. CONCLUSION: Deep brain stimulation in the ITP is safe and may be effective in the treatment of OCD. A multicenter evaluation of the safety and efficacy of ITP in OCD is currently in process.