Is primary prevention with antiepileptic drugs effective in brain tumors or brain metastases? / ¿Es efectiva la prevención primaria con anticonvulsivantes en tumores o metástasis cerebrales?

Patients with brain tumors –primary or metastatic- have an increased risk of presenting seizures during the course of their disease. So, prophylactic antiepileptic drugs have been proposed. However, the effects of this intervention are not yet clear. To answer this question, we searched in Epistemonikos database, which is maintained by screening multiple databases. We identified 12 systematic reviews including 80 studies overall. Twelve corresponded to randomized trials, but only two answered the question of interest. We extracted data, conducted a meta-analysis and generated a summary of findings table using the GRADE method. We concluded primary prevention with antiepileptic drugs might not reduce the risk of seizures, and it is associated to frequent adverse effects.

Los pacientes con tumores cerebrales, primarios o metastásicos, presentan riego de desarrollar convulsiones durante la evolución de su enfermedad, por lo que se ha propuesto el uso profiláctico de anticonvulsivantes. Sin embargo, el efecto de esta intervención no está claro. Para responder esta pregunta utilizamos la base de datos Epistemonikos, la cual es mantenida mediante búsquedas en múltiples bases de datos. Identificamos 12 revisiones sistemáticas que en conjunto incluyen ochenta estudios primarios. Doce corresponden a estudios aleatorizados, pero sólo dos responden la pregunta de interés. Extrajimos los datos, realizamos un metanálisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. Concluimos que la prevención primaria con anticonvulsivantes podría no disminuir el riesgo de convulsiones en tumores o metástasis cerebrales, y se asocia a efectos adversos frecuentes.

Is electroconvulsive therapy effective as augmentation in clozapine-resistant schizophrenia? / ¿Es efectivo el uso de terapia electroconvulsiva en el tratamiento de pacientes con esquizofrenia resistente que usan clozapina?

Clozapine is considered to be the most effective antipsychotic drug for patients with treatment resistant schizophrenia, but up to a third of the patients do not respond to this treatment. Various strategies have been tried to augment the effect of clozapine in non-responders, one of these strategies being electroconvulsive therapy. However, its efficacy and safety are not yet clear. Searching in Epistemonikos database, which is maintained by screening 30 databases, we identified six systematic reviews including 55 studies, among them six randomized controlled trials addressing clozapine-resistant schizophrenia. We combined the evidence using meta-analysis and generated a summary of findings following the GRADE approach. We concluded electroconvulsive therapy probably augments response to clozapine in patients with treatment resistant schizophrenia, but it is not possible to determine if it leads to cognitive adverse effects because the certainty of the evidence is very low.