Female offspring of women who participated in the Finnish evacuation during World War II were shown to be at increased risk for psychiatric hospitalization, according to the results of a recent study published in JAMA Psychiatry. The same risk was not seen for male children of maternal or paternal Finnish evacuees nor for female children of paternal Finnish evacuees.
To assess the impact of the Finnish evacuation to Sweden on the offspring of evacuees, researchers evaluated 93,391 offspring of Finnish people who were children during World War II (49.2% female; mean age in 2012, 45.4 years) for psychiatric hospitalization between 1971 and 2012 using the Finnish Hospital Discharge Register. They also evaluated the association between parental evacuation status as determined by the Finnish National Archive registry and offspring psychiatric hospitalization.
A total of 3.3% of participants had parents who were evacuated to Sweden during World War II.
An increased risk for psychiatric hospitalization was reported for female offspring born to evacuated mothers (hazard ratio [HR] 1.35; 95% CI, 1.00-1.81) but not to evacuated fathers (HR 0.86; 95% CI, 0.63-1.19). In a within-cousin analysis, similar trends were seen for female offspring born to evacuated mothers (HR 2.04; 95% CI, 1.04-4.01) and evacuated fathers (HR 1.04; 95% CI, 0.62-1.75).
According to the study authors, the association between psychiatric hospitalization and maternal evacuee status was driven by an increased risk for hospitalization for mood disorders among female participants with maternal evacuees compared with their cousins born to mothers who stayed with their families during the war (HR 4.68; 95% CI, 1.92-11.42). Similar results were reported after adjustment for parental depression.
Researchers noted no association between psychiatric hospitalization and parental evacuee status for the male participants.
In an interview with Psychiatry Advisor, Torsten Santavirta, PhD, of the Institute for Housing and Urban Research at Uppsala University, Sweden, and lead author on the study, explained that the present study agrees with previous results that found, “the elevated risk of psychiatric disorders was much higher for female evacuees as compared with their sisters.”
Dr Santavirta noted that future studies would, “explore the potential mechanisms behind the found association.”
Santavirta T, Santavirta N, Gilman SE. Association of the World War II Finnish evacuation of children with psychiatric hospitalization in the next generation [published online November 29, 2017]. JAMA Psychiatry. doi: 10.1001/jamapsychiatry.2017.3511