Researcher explores the role of stress in the rise of depression

By Sarah Binder

Concordia newcomer Mark Ellenbogen works in a sector where growth is a depressing fact.

He’s a developmental psychopathologist specializing in major depression, a disease expected to rank in five years as society’s No. 2 problem after heart disease in terms of productive years lost to disability.

The prevalence of major depression has grown every decade since the 1930s, making it a pressing health issue in developed and developing countries alike. “It’s pretty much a universal phenomenon,” Ellenbogen said in an interview.

“What’s even more disturbing is that the rates in young people are increasing in every successive generation. People are getting it earlier in life and more people are getting it.”

In North America, the rate of lifetime prevalence of major depression is about 16 per cent. In women, the rates are as high as 21 per cent, or about one in five.

“You’re talking about depression as a clinical medical disorder, where it’s so severe that they have trouble working or taking care of their family. They might lose weight, have trouble sleeping or getting out of bed, they can’t concentrate, they can’t function,” he explained.

Ellenbogen, 37, came to Concordia from the Université de Montréal on Canada Research Chair Tier 2 funding meant to keep up-and-coming scientists from leaving Canada.

He thinks that the increasing stress of our lives is the key to the rise in depression, and that is what he is exploring at the Department of Psychology and the Centre for Research in Human Development.

He directs a longitudinal study of families that is investigating the relationship of stress to the development of affective disorders such as major depression and bipolar disorder (manic depression), also known as mood disorders.

He is looking at the role of stress indicators such as the hormone cortisol, and at the different ways people cognitively process negative experiences in coping with stress.

Mood disorders appear to have both genetic and environmental root causes. Some of the genes involved have been identified, but they are not always directly associated with illness.

“You can have the high-risk gene and be no different than anyone else,” Ellenbogen said, “but if you have the gene and you’ve been exposed to multiple difficult life events — multiple divorces, loss of parents due to death, lost jobs — then you’re at high risk for depression.

“What this suggests is that environmental factors are not only important in themselves but they are important in triggering the action of genes. ”

Ellenbogen’s longitudinal study follows 150 children who come from 58 at-risk families where one parent has bipolar disorder, and from 50 control families.

The kids were between four and 12 when the study began in 1996 under Sheilagh Hodgins, then a U de M professor and now director of Forensic Mental Health Sciences at the London Institute of Psychiatry in the UK. Ideally, it will continue for another decade.

“We can safely estimate that half of the kids from the at-risk families will have a psychiatric disorder in their lifetime. Most of that will be major depression,” Ellenbogen said.

“They’re not just inheriting genes, they’re inheriting a special environment. They’re being raised in an environment that is incredibly stressful and chaotic and basically lacking structure.”

But many of the at-risk kids will not develop mental illness, and he wants to understand what “factors of resiliency” protect them. Understanding environmental factors could help break the cycle of intergenerational transmission of depression by early intervention that teaches parents ways of coping with stress.

Ellenbogen isn’t just disinterestedly watching the drama of these families unfold. A practicing clinical psychologist, he helps evaluate children showing signs of difficulty and suggests where to get treatment.

“Ethically, I have to,” he said. “Early treatment at the beginning of the first episode makes a huge difference in the progression of a disorder.”