Acute stress in childhood increases serious mental illness risk
medwireNews: The sudden death of a close family member in childhood is associated with an increased risk for serious mental illnesses in later life, study results show.
The researchers found that individuals who were exposed to the sudden, unexpected death (eg, accident or suicide) of a father or sibling before the age of 5 years were more likely to develop bipolar disorder or schizophrenia than those with a father or sibling who died due to illness.
"Our findings are in keeping with accumulating evidence which indicates that exposure to stress during early development can increase the risk of psychotic illness among those exposed," comment Mary Clarke (Royal College of Surgeons in Ireland, Dublin) and team.
Using the Finnish Population Register and the Cause of Death Register, the researchers identified 11,855 individuals, born in Helsinki between 1960 and 1990, who were exposed to the death of a father or sibling before the age of 5 years.
Of these, 6136 individuals had a father or sibling who died suddenly and 5719 individuals had father or sibling who died from an illness-associated cause.
Examination of data from the Finnish Hospital Discharge Register revealed that 165 individuals were diagnosed with bipolar disorder and 129 with schizophrenia in adulthood.
After accounting for gender, age at exposure to death, age at follow up, and parental history of psychiatric disorders, the team found that those with a father or sibling who died suddenly were 1.6 times more likely to develop bipolar disorder and 1.3 times more likely to develop schizophrenia than those whose relatives died from illness-related causes.
The team notes that the association between sudden death and bipolar disorder or schizophrenia in the offspring was not driven by paternal suicide, as the association remained significant when paternal suicide was excluded from the analysis.
Clarke et al conclude in Schizophrenia Research: "Our data suggests that the mode of death is important - sudden and violent death of a parent or sibling at an early developmental stage increases the risk of severe mental illness in those exposed."
By Mark Cowen, Senior medwireNews Reporter