Researchers at Cambridge University discovered what they believe may be the first biomarker for clinical depression. Their study, published in the Proceedings of the National Academies of Science (PNAS), concluded that teenage boys with depressive symptoms and elevated levels of the stress hormone cortisol were up to 14 times more likely to develop clinical depression.
Dr. Matthew Owens, one of the scientists who helped conduct the research, said in an email interview that the team wants to help the public and medical worlds better understand how depression works and how to treatin affected individuals.
“We hope that our study will shed further light on the complexities of what we currently call major depression,” Owens said. “It is in fact a very heterogeneous disorder that has many causes and in turn, preventative measures and treatments are likely to need to be different depending on the type of depressive disorder that an individual has.”
Ian Goodyer, Professor of Child and Adolescent Psychiatry at Cambridge University, said this breakthrough is the first of its kind. The significance of a biomarker, he said, lies in its ability to identify a distinct correlation between a biochemical trait and a specific disease.
“This is the first discovery of a biological marker for major depression in the population at large,” Goodyer said. “Ideally a biomarker should be stable over time, present in well individuals who later become unwell, indicate a pathophysiological process of some kind, likely to be revealing a sub type of a complex set of disorders that may have many biomarkers because of causal heterogeneity.”
Depression is a serious illness with a negative impact on society and the lives of those affected, sophomore Garrett Zyk said. After witnessing a friend experience clinical depression, Zyk said he realize the serious need to further research the disease.
“Studying depression is important so that way we can lower suicide rates and find out more about how the brain works,” Zyk said. “I have witnessed someone depressed, and it made me sad to watch because I just wanted to help them. It’s debilitating to the quality of people’s lives by always making them think negatively and not allowing them [to] progress socially and always being in an emotionally unstable state of mind.”
Owens said it is exceedingly important to explore the causes behind clinical depression. The illness, he said, affects a range of individuals and has a grim effect beyond the people who suffer directly from the disease.
“Clinical depression is a devastating illness for both individuals and society,” Owens said. “It is very common with as many as one in six being affected at some point in their lives. Reduced quality of life, reduction in academic performance and life chances can result and for some individuals, often young men, it can end in suicide. The financial costs to society are enormous in terms of medical treatment, reduction in work productivity and lost taxes.”
The effect of depression on an individual’s quality of life is hugely damaging, Gooyder said. It is treatable, he said, though the chance of relapse is significant.
“Recovery may be quick in mild disorders, perhaps a few weeks with no sequelas. There is around a 56 percent chance of relapse within five years of the first episode, however, although it is not clear if this risk increases for severe compared to mild depressions.”
Goodyer said he and his team plan to conduct further research regarding the biomarkers for depression and the physiological causes behind this disorder. Doctors will evaluate the condition of study participants later on in adulthood and perform new studies regarding the same topic.
“This paper is part of a large body of ongoing research investigating the causes, characteristics, treatment response and naturalistic outcomes of these conditions that emerge in the adolescent years,” Goodyer said. “We are currently planning a further follow up of the teenagers reported in the paper to see how they are in adulthood; we have completed a new treatment study, [and] we are mapping the structure and functions of the adolescent brain and mind to see if we can find neurocognitive circuits and functions that will tell us more about the at risk brain.”
Further research will help identify even more biological connections between the brain and the illness of depression, Owens said. These medical discoveries will play a key role in developing successful treatment options for the disease which will, in turn, improve the lives of millions.
“If we can identify different types of people with different psychological and biological profiles we may be able to improve prevention and treatment response, (which isn’t that great currently),” Owens said. “There are likely to be other markers involving genes, serotonin, for example, and more complex cell level markers. Combining biology, psychology and social factors to reach a better understanding of this common problem is one of the goals of this research.”
By Anna Wright