[Evoked potentials N200/P300 disorders and clinical phenotype in Cuban families with paranoid schizophrenia: a family-based association study].
BACKGROUND
N200 and P300 event-related evoked potentials provide sensitive measurements of sensory and cognitive function and have been used to study information processing in patients with schizophrenia and their unaffected first-degree relatives. Reduced amplitude and increased latency of N200 and P300 potentials have been consistently reported in schizophrenia. Thus, event-related evoked potentials abnormalities are promising possible biological markers for genetic vulnerability to schizophrenia.


OBJECTIVE
To assess the association of changes in latency, amplitude and topographic distribution of potentials N200 and P300 of patients with paranoid schizophrenia and their healthy first-degree relatives, in families with schizophrenia multiplex.


METHODS
We measured latency and amplitude of the N200 and P300 component of evoked potentials using an auditory odd-ball paradigm in 25 schizophrenic patients (probands) from 60 families multiply affected with paranoid schizophrenia, 23 of their non-schizophrenic first-degree relatives and 25 unrelated healthy controls, through a study of family association.


RESULTS
Schizophrenic patients and their relatives showed significant latency prolongation and amplitude reduction of the N200 and P300 waves compared to controls. Left-temporal as compared to right-temporal N200 and P300 were significantly smaller in schizophrenic patients and their non-schizophrenic first-degree relatives than in controls. Our results suggest that event-related evoked potentials abnormalities may serve as markers of genetic vulnerability in schizophrenia.


CONCLUSIONS
Confirming results of other researchers, this present study suggests that latency prolongation and amplitude reduction of the N200 and P300 waves and an altered topography at temporal sites may be a trait marker of paranoid schizophrenia.
Universidad Nacional del Este, Alto Paraná, Paraguay. Universidad de Integración Latinoamericana, Foz de Iguazú, Paraná, Brasil. Adress: Km. 16 Acaray, Avda. Mcal. López entre Mcal. Estigarribia y Padre Moleón, Minga Guazú  Paraguay. Email: seidelguerra@yahoo.es.
Seidel
S
Guerra López
Clínica de Rehabilitación de Salud Mental, Servicio Navarro de Salud, Pamplona, Navarra, España.
Migdyrai
M
Martín Reyes
Centro de Investigaciones Médicas, Facultad de Ciencias de la Salud, Universidad Nacional del Este, Minga Guazú, Paraguay.
María de Los Ángeles
Mde L
Pedroso Rodríguez
Departamento de Neurociencias de Cuba, Centro de Neurociencias de Cuba, La Habana, Cuba.
Adnelys
A
Reyes Berazain
Departamento de Neurociencias de Cuba, Centro de Neurociencias de Cuba, La Habana, Cuba.
Raúl
R
Mendoza Quiñones
Centros de Investigación y Tratamiento de las Adicciones (CITA) Dosrius, Barcelona, España.
Tania Martha
TM
Bravo Collazo
Departamento de Neurociencias de Cuba, Centro de Neurociencias de Cuba, La Habana, Cuba.
Thais
T
Días de Villarvilla
Universidad de Ciencias Médicas de Ciego de Ávila, Ciego de Ávila, Cuba.
María Julia
MJ
Machado Cano
Departamento de Neurociencias de Cuba, Centro de Neurociencias de Cuba, La Habana, Cuba.
María Antonieta
MA
Bobés León
D000328:Adult; D016022:Case-Control Studies; D003462:Cuba; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D005071:Evoked Potentials / Q000502:physiology*; D005192:Family Health; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D010641:Phenotype; D012563:Schizophrenia, Paranoid / Q000235:genetics / Q000503:physiopathology*
P300; paranoid schizophrenia; endophenotype; evoked potentials N200; event-related potentials