"Major depression has become one of the most pressing health issues in both developing and developed countries," says principal researcher Mark Ellenbogen, a professor at the Concordia Centre for Research in Human Development and a Canada Research Chair in Developmental Psychopathology.

"What is especially alarming is that depression in young people is increasing in successive generations. People are suffering from depression earlier in life and more people are getting it. We want to know why and how. We believe that stress is a major contributor."

From parent to child Ellenbogen and colleagues are particularly interested in the link between childhood stress and the development of clinical depression and bipolar disorder. His team is evaluating the stress of children who are living in families where one parent is affected by a mood disorder.

"Previous studies have shown that kids from at-risk families are at higher risk of having a psychiatric disorder in their lifetime," says Ellenbogen. "We know that they're not just inheriting these traits but they are also being raised in environment that is stressful, chaotic and lacking in structure. Our goal is to tease out how this type of environment influences these children's mental health in adolescence and adulthood."

cortisol, the stress hormone To assess stress levels, Ellenbogen is measuring the levels of the stress hormone, cortisol present in the children's saliva. Cortisol is a hormone that is produced by the body in response to stressful life events and challenges.

Ellenbogen's recent findings have shown that the adolescent offspring of at-risk families have higher salivary cortisol levels than kids from families without disorders. What's more, he found these elevated levels persist into young adulthood.

"Although there may be many causes to the rise in cortisol, this increase may be in part due to exposure to family stress and parenting style," says Ellenbogen. "We have not yet confirmed that these children then go on to develop mood disorders of their own. However, we have some exciting preliminary data showing that high cortisol levels in adolescences doubles your risk for developing a serious mood disorder in young adulthood."

Source: EurekAlert (Press Release)