Efectos de la estimulación no invasiva de la corteza motora en las pruebas sensoriales cuantitativas en sujetos sanos y con dolor crónico: una revisión sistemática y metaanálisis.
Publicado originalmente en la Revista Pain. 2020; 161(9):1955-1975. Traducción: Dr. Raúl Otoya
DOI:
https://doi.org/10.47924/neurotarget202175Palabras clave:
estimulación cerebral no invasiva, estimulación magnética transcraneal, estimulación transcraneal con corriente directa, pruebas sensoriales cuantitativasResumen
Uno de los posibles mecanismos de la modulación del dolor por estimulación de la corteza motora, empleando técnicas de Estimulación Cerebral no Invasiva (NIBS, por sus siglas en inglés), es a través de la restauración de las vías inhibitorias del dolor endógeno que se encuentran defectuosas. Sin embargo, todavía hay datos limitados en las Pruebas Sensoriales Cuantitativas (QST, por sus siglas en inglés), incluida la Modulación del Dolor Condicionado (CPM, por sus siglas en inglés) que respalden este mecanismo. Esta revisión sistemática y metanálisis tuvo como objetivo evaluar los efectos de la estimulación cerebral no invasiva de la corteza motora sobre la percepción del dolor, de acuerdo a lo registrado por los cambios en los resultados de las QST. Con esta finalidad, se realizaron búsquedas en bases de datos -hasta julio de 2019- que incluyeron ensayos controlados aleatorios donde realizaron NIBS en la corteza motora, tanto en poblaciones sanas (controles con estimulación simulada) y / o con dolor; los resultados fueron evaluados con QST incluyendo la CPM. La calidad de los estudios se evaluó mediante la herramienta Cochrane. Calculamos el Tamaño de Efecto de Hedge de los resultados de QST y CPM, sus intervalos de confianza del 95% (IC del 95%) y realizamos metaanálisis de efectos aleatorios. Se incluyeron 38 estudios (1178 participantes). Encontramos aumentos significativos del umbral del dolor en sujetos sanos (ES = 0,16, IC del 95% = 0,02 a 0,31, I2 = 22,2%) y población con dolor (ES = 0,48, 95% IC = 0,15 a 0,80, I2 = 68,8%) y resultados de CPM homogéneos y más altos (reducción de las calificaciones del dolor) en sujetos sanos (ES = -0,39, IC del 95% = -0,64 a -0,14, I2 = 17%) y población con dolor (ES = -0,35, IC del 95% = -0,60 a -0,11, I2 = 0%) en el grupo NIBS activo comparado con el de estimulación simulada. Estos resultados apoyan la idea de la modulación descendente de las vías endógenas del dolor mediante la estimulación de la corteza motora; lo cual podría constituir uno de los principales mecanismos de reducción del dolor evaluados por las QST. Este hallazgo podría ser un biomarcador predictivo y herramienta útil para el tratamiento personalizado del dolor crónico con NIBS.
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Derechos de autor 2021 Stefano Giannoni-Luza, Kevin Pacheco-Barrios, Alejandra Cardenas-Rojas, Piero F. Mejia-Pando, Maria A. Luna-Cuadros, Judah L. Barouh, Marina Gnoatto-Medeiros, Ludmilla Candido-Santos, Alice Barra, Wolnei Caumo, Felipe Fregni
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