Children who have at least one bipolar parent respond to everyday stress with higher levels of cortisol than the average child, according to a new international study led by Concordia University.
Researchers suggest that the stress hormone cortisol may be a key player in bipolar disorder.
The findings are the first to demonstrate that cortisol is more easily raised in these children in response to the regular stressors of everyday life.
“Previous research has shown that children of parents with bipolar disorder are four times as likely to develop mood disorders as those from parents without the condition,” said senior author Dr. Mark Ellenbogen, Canada Research Chair in Developmental Psychopathology at Concordia University. “The goal of our study was to determine how this is happening.”
Ellenbogen and a research team had previously shown that cortisol levels in children with a bipolar parent were higher than kids whose parents did not have the disorder.
The new study, however, measured cortisol levels in these same children during both chronic and short-term stress periods. In either situation, kids of parents with bipolar disorder showed a greater increase in cortisol than those of parents without the disorder.
“Our study demonstrates that affected children are biologically more sensitive to the experience of stress in their natural and normal environment compared to unaffected peers,” Ellenbogen said. “This higher reactivity to stress might be one explanation of why these offspring end up developing disorders and is a clear risk factor to becoming ill later on.”
“We think we might be beginning to understand where we can intervene to actually prevent this increased sensitivity from developing,” he said.
Ellenbogen suggested that such a sensitivity develops during childhood, and that teaching both parents and offspring how to better cope with stress and deal with problems before they fester could have a profound impact on this population.
The study is published in Psychological Medicine.
Source: Concordia University