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Trastorno afectivo estacional y anormalidades dependientes de la estación de la supresión de la melatonina por la luz
C Thompson1, D Stinson, A Smith
1Department of Psychiatry, University of Southamptom, Royal South Hants Hospital, UK.
Lancet (London, England)
|September 22, 1990
Resumen
Los pacientes con trastorno afectivo estacional (SAD) muestran una sensibilidad a la luz alterada, mostrando una mayor sensibilidad en invierno y una menor sensibilidad en verano en comparación con los controles. Esta variación estacional en la respuesta a la luz está relacionada con el SAD.
Área de la Ciencia:
- Cronobiología cronobiología.
- La neuroendocrinología en neuroendocrinología.
- La psiquiatría es la psiquiatría.
Sus antecedentes:
- El trastorno afectivo estacional (TEA) es un trastorno del estado de ánimo con patrones estacionales.
- La secreción de melatonina está regulada por la exposición a la luz y juega un papel en los ritmos circadianos.
- La sensibilidad a la luz alterada puede contribuir a la fisiopatología del SAD.
Objetivo del estudio:
- Para investigar las variaciones estacionales en la sensibilidad a la luz en pacientes con SAD.
- Para comparar la supresión de la melatonina inducida por la luz entre pacientes con SAD y controles sanos a través de las estaciones.
- Para determinar si los pacientes con SAD exhiben una sensibilidad diferente a la luz en invierno frente al verano.
Principales métodos:
- Doce pacientes con SAD y once controles sanos se sometieron a pruebas de exposición a la luz (2000 lux frente a 300 lux) durante el invierno y el verano.
- La supresión de la secreción de melatonina se midió como un indicador de sensibilidad a la luz.
- Las diferencias en la supresión de la melatonina entre las intensidades de luz se analizaron estacionalmente.
Principales resultados:
- Los pacientes con SAD demostraron una variación estacional significativa en la sensibilidad a la luz, a diferencia de los controles.
- En invierno, los pacientes con SAD mostraron una mayor sensibilidad a la luz (supersensibilidad).
- En verano, los pacientes con SAD mostraron una sensibilidad reducida a la luz (subsensibilidad).
Conclusiones:
- El SAD está asociado con un patrón estacional distinto de sensibilidad a la luz alterada.
- Estos hallazgos sugieren un potencial mecanismo neuroendocrino subyacente a la recurrencia estacional del SAD.
- Las intervenciones terapéuticas de luz para el SAD pueden necesitar considerar las diferencias estacionales en la respuesta a la luz.
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