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Medicina & Laboratorio

2020, Número 2

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Medicina & Laboratorio 2020; 24 (2)


Homocisteína y trastornos neurocognitivos. ¿Una luz al final del túnel?

Vizcaíno-Salazar GJ

Idioma: Español
Referencias bibliográficas: 98
Paginas: 111-129
Archivo PDF: 481.98 Kb.


RESUMEN

El deterioro cognitivo es uno de los procesos que acompañan al envejecimiento y puede depender de factores nutricionales, genéticos o ambientales. La identificación de factores de riesgo modificables proporciona un enfoque esencial para la prevención de dicho deterioro y de los trastornos neurocognitivos. Uno de los factores de riesgo involucrados es la elevada concentración de homocisteína plasmática, la cual se ha relacionado con hallazgos histopatológicos en demencia senil y enfermedad de Alzheimer. Los diferentes estudios sobre esta asociación revelan inconsistencia o contradicción en los resultados. El propósito de esta revisión es relacionar la posible interacción de tres factores en la instalación y progresión del deterioro neurocognitivo: a) factores de tipo nutricional (homocisteína, ácido fólico y vitamina B12), b) la utilización de pruebas para el diagnóstico de disfunción o deterioro cognitivo como el Mini Examen del Estado Mental, y c) la presencia de variantes genéticas polimórficas de la enzima metilentetrahidrofolato reductasa. Una consecuencia directa de esta triple relación es que el tratamiento con ácido fólico y vitamina B12 logra disminuir las elevadas concentraciones de homocisteína plasmática, asumiendo que una mejoría en los síntomas clínicos de deterioro cognitivo puede retrasar los cambios relacionados con progresión a estados demenciales. La intervención temprana mediante políticas de promoción y prevención de la salud mental puede ser efectiva si se comienza con la administración de ácido fólico y vitamina B12 en los estadios iniciales de la alteración cognitiva, logrando así reducir sus funestas consecuencias. Las políticas de salud pública centradas en la salud mental de ancianos pueden identificar a las personas con disfunción cognitiva inicial a través de la promoción de la salud y medidas preventivas; en esta etapa puede ser posible la administración de vitaminas B para reducir o minimizar la pro- gresión del deterioro cognitivo, que podría conducir a trastornos neurocognitivos como la demencia y la enfermedad de Alzheimer.


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