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ALTERACIONES METABÓLICAS INDUCIDAS POR LA DEFICIENCIA DE LA HORMONA DE CRECIMIENTO: BENEFICIOS DE LA TERAPIA SUSTITUTIVA CON HORMONA DE CRECIMIENTO. Revisión

Revista Venezolana de Endocrinología y Metabolismo 10/2003; 1(3).

ABSTRACT La hormona de crecimiento (HC) interviene en la regulación de la actividad cardiovascular 1 y se ha demostrado un aumento en la morbilidad y mortalidad por enfermedad cardiovascular en pacientes con deficiencia de hormona de crecimiento, diagnosticada tanto en la niñez como en edad adulta 2 . Adultos con deficiencia de HC presentan un incremento en diversos índices de riesgo cardiovascular tales como hiperlipidemia, un aumento en la masa de grasa corporal, aterogénesis prematura, disminución de la actividad fibrinolítica, aumento en la resistencia periférica a la insulina, alteraciones en el metabolismo de los carbohidratos y alteraciones en la estructura y función cardiaca. A continuación revisaremos en cierto detalle las alteraciones metabólicas detectadas en pacientes con deficiencia de la hormona de crecimiento y los cambios favorables que se ven en estos sujetos du-rante la administración de esta hormona. Se presentan datos reportados en los últimos 5-7 años en adultos y datos en niños y adolescentes que recién comienzan a aparecer en la literatura. COMPOSICIÓN CORPORAL Estudios recientes en niños, adolescentes y adultos con deficiencia de HC han demostrado anorma-lidades en su composición corporal, con una reducción en la masa magra y un aumento en la masa grasa con una obesidad de tipo abdomino/vis-ceral. La terapia con HC reduce el volumen del tejido adiposo y aumenta la cantidad de músculo. Koranyi y cols. 3 describen un aumento de la masa grasa en adultos jóvenes con deficiencia de HC diagnosticada en la niñez, con una disminución en la masa magra y en la fuerza muscular al comparárseles con pacientes con deficiencia de HC de aparición en edad adulta. El aumento de la masa muscular durante el tratamiento con hormona de crecimiento fue mayor en pacientes con deficiencia de HC diagnosticada en la niñez, de manera de que después de 5 años de tratamiento no se detectaba ninguna diferencia en-tre el grupo diagnosticado en la niñez o en edad adulta en ninguna de las variables relacionadas a composición corporal. Korumaru y cols. 4 reportaron un aumento lineal en el peso corporal de niños deficientes de HC con y sin tratamiento. El índice de obesidad disminuyó 6,1% en varones y 9,7% en hembras durante la terapia con HC, mientras que la relación cintura/ cadera no cambió en forma significativa en ambos sexos. La grasa corporal disminuyó significativamente tanto en varones como en hembras durante los primeros 6 meses de tratamiento, pero permaneció constante en varones y aumentó en hembras después de 2 años de tratamiento; la masa muscular aumentó signifi-cativamente en ambos sexos durante el periodo de tratamiento. Después de descontinuar el tratamiento con HC y durante un periodo de observación de 2 años, Johansson y cols. 5 notaron que el porcentaje de masa magra disminuyó, mientras que el porcentaje de grasa corporal y la grasa del tronco aumentaron en adolescentes deficientes de HC, con una tendencia similar pero menos marcada en controles sanos.

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