Correlación entre las lesiones desmielinizantes y el deterioro de las funciones ejecutivas en una muestra de pacientes mexicanos con esclerosis múltiple / Correlation between demyelinating lesions and executive function decline in a sample of Mexican patients with multiple sclerosis

Antecedentes: La esclerosis múltiple (EM) se caracteriza por una gran diversidad de síntomas neurológicos de entre los cuales el deterioro cognitivo recientemente ha cobrado una especial relevancia. Hasta el momento la evidencia acerca de una correlación entre las características de las lesiones y el deterioro cognitivo específico aún no es concluyente. Objetivo: Analizar si existe una correlación entre las características de las lesiones desmielinizantes y el desempeño de las funciones ejecutivas básicas en estos pacientes. Pacientes y métodos: Se incluyeron 21 pacientes adultos con puntaje de 0-5 en la escala de Kurtzke, sin exacerbaciones de la enfermedad en los 3 meses previos a la evaluación. Se les aplicaron las pruebas de Stroop y elWisconsin Card Sorting Test (WCST). La localización de las lesiones fue determinada por resonancia magnética a través de un observador experto y cegado. Resultados: Las lesiones desmielinizantes se distribuyeron con mayor frecuencia en los lóbulos occipitales y frontales. En el Stroop se observó que a medida que se incrementa la demanda cognitiva en cada sección de la prueba, aumentan el tiempo de reacción y el número de errores. En el WCST, un 33,33% presentó un deterioro medio a moderado. No se encontró una relación entre la lesiones desmielinizantes –localización, tamaño y suma total– y los puntajes de las pruebas aplicadas. Conclusión: En la explicación del deterioro cognitivo en la EM se deben considerar no solo las lesiones desmielinizantes, sino también otros factores biológicos, psicológicos y sociales (AU)

Background: Multiple Sclerosis (MS) is characterised by several neurological symptoms including cognitive impairment, which has recently been the subject of considerable study. At present, evidence pointing to a correlation between lesion characteristics and specific cognitive impairment is not conclusive. Objective: To investigate the presence of a correlation between the characteristics of demyelinating lesions and performance of basic executive functions in a sample of MS patients. Patients and methods: We included 21 adult patients with scores of 0 to 5 on the Kurtzke scale and no exacerbations of the disease in at least 3 months prior to the evaluation date. They completed the Stroop test and the Wisconsin Card Sorting Test (WCST). The location of the lesions was determined using magnetic resonance imaging (MRI) performed by a blinded expert in neuroimaging. Results: Demyelinating lesions were more frequently located in the frontal and occipital lobes. The Stroop test showed that as cognitive demand increased on each of the sections in the test, reaction time and number of errors increased. On the WCST, 33.33% of patients registered as having moderate cognitive impairment. No correlation could be found between demyelinating lesion characteristics (location, size, and number) and patients’ scores on the tests. Conclusion: Explanations of the causes of cognitive impairment in MS should examine a variety of biological, psychological, and social factors instead of focusing solely on demyelinating lesions (AU)

[Correlation between demyelinating lesions and executive function decline in a sample of Mexican patients with multiple sclerosis]. / Correlación entre las lesiones desmielinizantes y el deterioro de las funciones ejecutivas en una muestra de pacientes Mexicanos con esclerosis múltiple.

BACKGROUND: Multiple Sclerosis (MS) is characterised by several neurological symptoms including cognitive impairment, which has recently been the subject of considerable study. At present, evidence pointing to a correlation between lesion characteristics and specific cognitive impairment is not conclusive. OBJECTIVE: To investigate the presence of a correlation between the characteristics of demyelinating lesions and performance of basic executive functions in a sample of MS patients. PATIENTS AND METHODS: We included 21 adult patients with scores of 0 to 5 on the Kurtzke scale and no exacerbations of the disease in at least 3 months prior to the evaluation date. They completed the Stroop test and the Wisconsin Card Sorting Test (WCST). The location of the lesions was determined using magnetic resonance imaging (MRI) performed by a blinded expert in neuroimaging. RESULTS: Demyelinating lesions were more frequently located in the frontal and occipital lobes. The Stroop test showed that as cognitive demand increased on each of the sections in the test, reaction time and number of errors increased. On the WCST, 33.33% of patients registered as having moderate cognitive impairment. No correlation could be found between demyelinating lesion characteristics (location, size, and number) and patients' scores on the tests. CONCLUSION: Explanations of the causes of cognitive impairment in MS should examine a variety of biological, psychological, and social factors instead of focusing solely on demyelinating lesions.