Early death of a parent as an etiological factor in schizophrenia.

Results of three separate studies comparing adult schizophrenic and other psychiatric patients suggest that premature death of a parent may be a contributing factor in the etiology of schizophrenia. This finding was not attributable to a genetically-linked tendency toward suicide in parents. Parental death was found to occur earlier among schizophrenics than other patients and, in two studies, to be most frequent among schizophrenics with predominantly paranoid symptoms.