Members of the young Jewish community attend a commemoration ceremony for Holocaust victims in front of the synagogue in Vienna [File].
(photo credit: REUTERS)
Second-generation survivors of the Holocaust whose parents were infants during World War II are at a higher risk of suffering from a more-severe course of schizophrenia than those whose parents were not. The study was just published in Schizophrenia Research.
This was a surprising new finding from University of Haifa researchers, given the fact that they had previously found no difference in the risk of developing schizophrenia between second-generation Holocaust survivors and those whose parents were not exposed to the Holocaust.
It is likely this has been transmitted from the parental environment to the child, commented Prof. Stephen Levine, the lead author of the study. The study was carried out by Levine Prof. Itzhak Levav of the community mental health department at the university, along with Inna Pugachova, Rinat Yoffe, and Yifat Becher of the Health Ministry.
The study was based on data on 51,233 individuals who immigrated to Israel through 1966 that was supplied by the Health and Interior Ministries, with funds from Israel Science Foundation. Those studied included Jews who experienced the Holocaust directly, while the comparison group comprised of individuals who immigrated to Israel before the Holocaust began in their native countries. All of the second-generation subjects were born between 1948 and 1989 and were followed through 2014 to determine whether or not they suffered from schizophrenia.
The effects of exposure to the Holocaust among the children of survivors is the subject of disagreement among researchers. Clinic-based studies have found that trauma increases psychopathology in the offspring of Holocaust survivors, while community-based studies have found that there is no such effect among adults, as noted by Levav and colleagues in two large representative samples in Israel. The researchers sought to examine whether parental Holocaust exposure is associated with schizophrenia among second-generation survivors. The good news, the researchers said, is that the association was not significant.
But a more specific inquiry showed that offspring of mothers with Holocaust exposures in the womb only were 1.7 times more likely to have a more severe course of the disorder. Children of mothers exposed to the Holocaust in the womb and thereafter were 1.5 times more likely to have a more severe course than persons not exposed, they found.
Among offspring to fathers exposed in the womb and afterwards were 1.5 times more likely to have such a severe disorder, and those whose fathers exposed at ages one and two had offspring with similar risk to have a worse case of the disorder than persons not exposed .
Trans-generational genocide exposure was unrelated to the risk of schizophrenia in the offspring, but was related to a course of deterioration in schizophrenia during selected parental critical periods of early life. This implies an epigenetic mechanism – arising from environmental influences on the way genes expressed themselves.
The findings, they said, should influence health policy decision makers about benefits to refugees who suffered from extreme adversity and reach conclusions on existing results regarding the trans-generational transfer of the effects of famine and stress in parental early life.