Intra-familial Correlations of Symptoms and Clinical Characteristics in Multiplex Korean Families with Schizophrenia / 신경정신의학

OBJECTIVES: This study aims at examining familial associations of symptoms and clinical characteristics in affected sibling or relative pairs of schizophrenia as an effort to identify genetically homogeneous phenotypes. METHODS: Forty-seven relative pairs with DSM-IV diagnosis of schizophrenia from thirty-five Korean families multiply affected with schizophrenia were ascertained. Direct interviews were done using the Korean version of Diagnostic Interview for Genetic Studies (DIGS). The Krawieka Rating Scale and the Schedule for the Deficit Syndrome were also applied for further evaluation of psychopathologies. Intra-familial concordances and correlations of clinical characteristics and symptoms were tested using chi-squared-test and Spearman's correlation. RESULTS: Significantly high concordance rate within relative pairs was found for the diagnosis of paranoid vs. non-paranoid subtype (chi-squared=7.623, p=0.006, df=1). Deficit vs. non-deficit syndrome also showed significant concordance (chi-squared=3.850, p= 0.0497, df=1). Among single symptom items in DIGS, only 'auditory hallucination' showed significant concordance rate (chi-squared= 5.503, p=0.019, df=1). Factor analysis for symptoms items in the Krawiecka Rating Scale indicated three symptom dimensions; negative, psychotic and affective. Psychotic (rho=0.442, p=0.003) and affective dimension scores (rho=0.427, p=0.004) showed significant intra-familial correlations. Age at onset of recognized psychotic symptoms showed significant correlation only within the male sibling pairs. CONCLUSION: Familial factors, possibly genetic factor contribute to the phenotypic characteristics of paranoid vs. non-paranoid subtype, deficit vs. non-deficit syndrome, auditory hallucination, and affective syndrome. It supports their use in the delineation of homogeneous subgroups for future genetic studies

Genetic and Clinical Characteristics of Multiplex Schizophrenia Families / 신경정신의학

OBJECTIVES: This study aims at exploring genetic and clinical characteristics of multiplex Korean families with schizophrenia. METHODS: Thirty-three families having two or more schizophrenics by DSM-IV criteria within the second degree relatives were obtained from the clinics of general hospitals and mental hospitals. Sixty-nine affected and forty-five unaffected subjects from these families were interviewed using Korean version of Diagnostic Interview for Genetic Studies. Krawieka Rating Scale and The Schedule for the Deficit Syndrome were also applied for further evaluation of psychopathologies of the patients. Patterns of inheritances of the disease were analyzed by the inspection of the pedigrees. Parent-of-origin effect was evaluated by the comparison of the occurrence rate and the clinical characteristics between the subgroups of maternal and paternal origins. RESULTS: There were similar rates of maternal and paternal transmission in the families for which unilineal transmission of the disease was estimated. Only one family showed bilineal transmission. Observed patterns of transmission were not compatible with the recessive single locus model or sex-linked model. The most frequently observed non-schizophrenic disorders in these families were personality disorders/traits of schizophrenia spectrum. We could not find any clinical characteristics which might be unique to the patients from multiplex families. Parent-of-origin effect was not suggested. CONCLUSION: This study provides preliminary clinical and genetic data on the multiplex schizophrenia families which could be used for the determination of the genetic parameters and the boundaries of the phenotype in the linkage analyses.