Genetics, environment and psychopathology / editors, Sarnoff A. Mednick [and others].

Date:
1974
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: Genetics, environment and psychopathology / editors, Sarnoff A. Mednick [and others]. Source: Wellcome Collection.

    42/364 (page 26)
    26 David Rosenthal adoptees themselves rather than their relatives. The design asks the question : What is the fate of offspring of schizophrenic parents when these offspring are reared adoptively? In this study, the starting point is the approximately 10,000 biological parents of our pool of adoptees. A search was conducted to see who among these parents had a file in the Psychiatric Register. The hospital records of each such parent were reviewed in detail by a psychiatrist who completed a prescribed form which was reviewed independently by the American investigators. If we agreed that the parent's diagnosis belonged in our spectrum of schizophrenic disorders, or was a clearcut or possible case of manic- depressive psychosis, the adopted-away child of that parent was chosen as an index case. From among the remaining adoptees, we chose as controls those whose both biological parents had no known psychiatric history, i.e., neither parent had a file in the Psychiatric Register. Controls were matched to the index cases for sex, age, age at transfer to the adopting family, and the socioeconomic status of the adopting family. The index and control subjects were invited to participate in a study of the relationship between environment and health. We were able to achieve almost 80% cooperation, an acceptable figure, and the two groups did not differ in this respect. At this time, we are able to report on 76 index cases and 67 controls. The subjects were given a semi- structured psychiatric interview by Dr. Joseph Welner that lasted from 3 to 5 hours. Each subject also had one and a half days of psycho¬ logical testing, but we will not be able to present the test findings now. The examinations of all subjects spanned a period of four years. The main finding of this study is that there is a significantly greater number of schizophrenic spectrum disorders among the index cases than among the controls. Three cases were called clearcut schizo¬ phrenia by Dr. Welner. All three were index cases. However, only one of these had been hospitalized for the disorder. As a matter of fact, the rate for hospitalized schizophrenia and for diagnosed schizophrenia tends to be appreciably lower than the rates usually found in Scandi¬ navia for the nonadopted offspring of schizophrenics. Therefore, this study leads us to the twofold conclusion that heredity contributes significantly to the development of schizophrenic spectrum disorder, and that adoptive rearing may contribute to the reduced expressivity of such disorder. In both studies presented, evidence is accumulating