February 18, 2014
Saliva-Based Test Predicts Risk Of Future Clinical Depression In Boys
Brett Smith for redOrbit.com - Your Universe Online
Most teenage boys go through hard times and some can even get depressed. A new saliva-based test can determine if these minor bouts of depression are foreshadowing major depression later in life, according to a new study based in the United Kingdom.
Published in the Proceedings of the National Academies of Science (PNAS), the study found that teenage boys with high levels of the stress hormone cortisol and mild depression symptoms were up to 14 times more likely to experience clinical depression later in life, compared to those with low or normal cortisol levels.
The study is unique in that it offers a metric for determining risk of a condition of the mind, something historically considered somewhat ephemeral.
"This is the emergence of a new way of looking at mental illness," said study author Joe Herbert, of the University of Cambridge in the UK. "You don't have to rely simply on what the patient tells you, but what you can measure inside the patient.”
In the study, the scientists collected spit samples from over 1,800 teenagers and assessed levels of cortisol contained in the saliva, along with self-reported data on signs of depression. The teenagers were then divided into one of four groups based on both their cortisol levels and their symptoms of depression.
After tracking the study cohort for 12 to 36 months, the study team determined which group was most likely going to develop clinical depression and other psychiatric conditions in the future.
While the researchers found that boys with higher levels of cortisol and depressive symptoms were 14 times more likely to develop clinical depression, this difference was less significant in female teenage participants, who were four times more likely to develop clinical depression. The researchers took this as a sign that gender variances affect how depression progresses.
The researchers said they hope the newly discovered biomarker for depression will allow primary care services to identify high-risk boys and consider new strategies for this segment of the population.
“This new biomarker suggests that we may be able to offer a more personalized approach to tackling boys at risk for depression,” said study author Matthew Owens, a research associate at University of Cambridge. “This could be a much needed way of reducing the number of people suffering from depression, and in particular stemming a risk at a time when there has been an increasing rate of suicide amongst teenage boys and young men.”
In discussing the study with BBC News, Sam Challis, from the UK mental health charity Mind, pointed out that there are many factors besides the level of cortisol that play a role in the development of depression.
"This study claims there is a biomarker linked to depression, but it's important to bear in mind that many factors play a part in depression, such as life events, genetic factors, side effects of medication and diet,” he said. "However, this research could help identify those who may need extra support.”
"We know that it is possible to recover from a mental health problem, and this is more likely for those who seek help straight away,” he added.