ABSTRACT
While most patients with depression respond to pharmacotherapy and psychotherapy, about one-third will present treatment resistance to these interventions. For patients with treatment-resistant depression (TRD), invasive neurostimulation therapies such as vagus nerve stimulation, deep brain stimulation, and epidural cortical stimulation may be considered. We performed a narrative review of the published literature to identify papers discussing clinical studies with invasive neurostimulation therapies for TRD. After a database search and title and abstract screening, relevant English-language articles were analyzed. Vagus nerve stimulation, approved by the U.S. Food and Drug Administration as a TRD treatment, may take several months to show therapeutic benefits, and the average response rate varies from 15.2-83%. Deep brain stimulation studies have shown encouraging results, including rapid response rates (> 30%), despite conflicting findings from randomized controlled trials. Several brain regions, such as the subcallosal-cingulate gyrus, nucleus accumbens, ventral capsule/ventral striatum, anterior limb of the internal capsule, medial-forebrain bundle, lateral habenula, inferior-thalamic peduncle, and the bed-nucleus of the stria terminalis have been identified as key targets for TRD management. Epidural cortical stimulation, an invasive intervention with few reported cases, showed positive results (40-60% response), although more extensive trials are needed to confirm its potential in patients with TRD.
ABSTRACT
Recent research suggests that early intervention in psychosis might improve the chances of recovery and may even be able to prevent the onset of psychotic disorders. Clinical intervention in subjects at ultra high risk (UHR) of psychosis can have three different objectives. The first aim is to improve the 'prodromal' symptoms and problems that subjects usually present with. The second is to reduce the risk of the subsequent onset of frank psychosis. The third objective is to minimize the delay before the initiation of antipsychotic treatment in the subgroup of UHR subjects that go on to develop a first episode of psychosis. Both pharmacological and psychological interventions appear to be effective in reducing the severity of presenting symptoms in UHR subjects. Clinical trials of the impact of these interventions on the risk of subsequent transition to psychosis have been positive, but have involved small samples, and thus the issue of whether the effects persist in the long term remains to be determined. The monitoring of UHR subjects for the first signs of frank psychosis is an effective means of reducing the delay between the onset of the first episode and the start of antipsychotic treatment. Follow-up studies are required to test whether the reduction in this delay leads to an improved long term outcome. To date, the majority of the interventions that have been used in UHR subjects, such as case management, antipsychotic medication, and cognitive behavior therapy have previously been employed in patients with established psychosis. However, it is possible that treatments that are not normally used in patients with psychotic disorders may prove effective when applied at this stage.
Estudos recentes sugerem que a intervenção precoce na psicose poderia melhorar as chances de recuperação e inclusive evitar o início de transtornos psicóticos. A intervenção clínica para indivíduos em ultra alto risco (UAR) de psicose pode ter três objetivos diferentes. O primeiro é o de melhorar os sintomas e problemas "prodrômicos" que os indivíduos normalmente apresentam. O segundo é o de reduzir o risco de psicose franca subsequente. O terceiro objetivo é o de minimizar a demora antes do início do tratamento antipsicótico no subgrupo de indivíduos em UAR que evoluem para um primeiro episódio psicótico. Tanto as intervenções farmacológicas como as psicológicas parecem ser eficazes para reduzir a gravidade dos sintomas apresentados pelos indivíduos em UAR. Ensaios clínicos sobre o impacto dessas intervenções no risco de transição subsequente para psicose foram positivos, mas envolveram amostras pequenas e, dessa forma, a questão de se os efeitos persistem ou não no longo prazo ainda precisa ser resolvida. O monitoramento dos indivíduos em UAR para os primeiros sinais de psicose franca é uma forma eficaz de reduzir a demora entre o início do primeiro episódio e o começo do tratamento antipsicótico. Estudos de acompanhamento são necessários para testar se a redução desse tempo leva a um desfecho melhor no longo prazo. Até hoje, a maioria das intervenções para indivíduos em UAR, como manejo de caso, medicação antipsicótica e terapia cognitivo-comportamental, foram empregadas anteriormente em pacientes com psicose estabelecida. No entanto, é possível que tratamentos que não são normalmente utilizados para pacientes com transtornos psicóticos possam ser eficazes ao serem aplicados nesse estágio.