Sl. Varma et I. Sharma, PSYCHIATRIC MORBIDITY IN THE 1ST-DEGREE RELATIVES OF SCHIZOPHRENIC-PATIENTS, British Journal of Psychiatry, 162, 1993, pp. 672-678
First-degree relatives (FDRs) of 1018 schizophrenic and 812 control pr
obands were investigated. Psychiatric morbidity was present in 34.8% o
f FDRs of schizophrenic probands and in 9.2% of FDRs of controls. Ther
e was significantly more psychiatric illness in the siblings and paren
ts than in the offspring of both schizophrenic and control subjects. T
he morbidity risks for schizoid-schizotypal personality disorders, can
nabis-use disorder and paranoid personality disorder were significantl
y higher in the FDRs of schizophrenic patients than in those of contro
ls, suggesting a biological relationship.