By David Saunders | UPDATED: 12:28, 19 December 2019
Post-Traumatic Stress Disorder is a truly harrowing condition but earlier diagnosis could mean more people receive the help they so desperately need. GlobalData’s Natalie Healey reports on a new blood test that has potential to determine the condition as accurately as a psychiatric assessment.
For the last 40 years, Dr Charles Marmars’ patients have shared with him some of the most harrowing events imaginable. From veterans recalling battleground horrors, to sexual assault survivors, to people disturbed from hideous road accidents, the chairman of psychiatry and director of the Post-traumatic Stress Disorder (PTSD) Research Program at NYU Langone Health has heard it all.
The problem is, he often hears it very late, after patients have been suffering for years. To tackle this problem, a high-throughput, efficient screening mechanism for the illness is sorely needed.
Working with several other PTSD leaders and institutions, including Dr Frank Doyle, Dean of Harvard John A Paulson School of Engineering and Applied Sciences, as well as Dr Marti Jett from the US Army Medical Research and Development Command, the NYU team set out to develop a blood-based biomarker test to diagnose PTSD in veterans. They recruited 83 men with confirmed PTSD who had served in Iraq or Afghanistan. An equal number of healthy controls, who had also been deployed to war zones but did not have the condition, were chosen too.
The scientists tested nearly one million biomarkers. Using a combination of techniques, including machine-learning and genomic and molecular testing, they were eventually able to narrow them down to 28 markers, which would form the basis of a ‘PTSD blood test’.
“The final 28 markers performed well. They were able to accurately classify who went to Iraq and Afghanistan and came back with PTSD as validated by four hour, super-expert clinical assessments,” reveals Marmar.
Next on the agenda was replicating the work, applying the blood test to an independent group of veterans who had been assessed using the standard clinical questionnaire for the condition. Luckily, the replication study was a success and the team found the blood test gave an accuracy rate of 77%.
The biomarker test is an incredible start. With further validation, the US Department of Defense is even considering using it as a screening tool, to identify service members before and after deployment with features of unresolved PTSD. But far more research will be required before the test is used in standard care.
Marmar says: “We don’t yet know why these biomarkers are so important. Or why PTSD results in these changes. Additionally, the tool has only been tested in male veterans so far. It could be completely different for women, or men with PTSD that does not relate to the battleground.
“In a perfect world, we’ll find some universal features that are associated with PTSD, or not having PTSD, in both men and women, and in veterans and civilians. And maybe eventually in children and adolescents But first, there’s a lot of work to do.”