The end of war brings home soldiers, and accompanying many of these veterans is post-traumatic stress disorder, PTSD. This disorder occurs after experiencing a stressful or frightening event and often makes veterans feel and act as though they are reliving combat.

UCSB researchers in the College of Engineering discovered that PTSD can be detected in the bloodstream, and the team is in the initial phases of developing a portable field device for soldiers to quantitatively diagnose the disorder. The Army-funded research focuses on the systems and computational engineering aspect of diagnosing PTSD.

Until now, physicians have lacked precise medical tests to determine whether someone suffers from PTSD or not. It is usually diagnosed through psychiatric counseling and observable signs, such as hyper-arousal and nightmares. Due to the inaccuracy of diagnosing PTSD, some soldiers come back from the battlefield undiagnosed and untreated, leading to consequences, such as depression and even suicide.

Gunjan Thakur, a postdoctoral researcher in the College of Engineering, said that the researchers focus on identifying the chemical changes that occur after a traumatic event.

“The main goal is to understand the disease or disorder [and] the mechanism. How do such bad events that happen in one’s life… change the chemistry?” Thakur said. “That is the ultimate goal. The immediate goal is to figure out what do you measure so that we know that somebody has it.”

PTSD can be identified in the bloodstream due to chemical changes that occur in the body when a person experiences stress associated with fearful events. For example, PTSD causes changes to the shape and volume of the limbic system, which in turn releases different chemicals. Changes can manifest in irregular methylation patterns, which are additions of methyl groups to DNA, that affect how proteins transcribe and ultimately express genes.

The researchers worked with thousands of soldiers to conduct clinical trials in order to single out the changes that take place in the body.

Kelsey Dean, graduate student in the Department of Chemical Engineering, described how the group analyzed specific biomarkers in the data sets.

“We would be looking for certain small molecules to check their levels and say if this small molecule was too high and this one is too low, then this combination makes a person have PTSD,” Dean said. “A lot is known in the body about different pathways and how things function, like what is related to stress, immune system — just basic kind of biological processes. So we can use that information to say that this gene talks to this gene … and how this cycle is deregulated in a person with PTSD.”

The researchers are still in the initial phases of the project and do not yet know the PTSD “signature,” making it difficult to establish the most useful diagnostic test. Some ideas include a device similar to that of a diabetes blood glucose test, a pregnancy test or even a simple blood test. One thing that is known is the statistical analysis behind the test.

Department Chair of Chemical Engineering Frank Doyle said that the researchers used statistical tools and inference along with the computer models for simulation.

“We make mathematical models of what are called signaling networks. What signaling networks describe are how when genes make proteins, how those proteins are changed or how they interact and react with other proteins to give rise to a signal that then tells a cell if it is in a stressed state,” Doyle said. “So if all I wanted to do was take hundreds of thousands of measurements and look for patterns, I wouldn’t need biology, I would just need statistics. We simulate these networks, we analyze the networks, we bring powerful statistical tools to probing the data and that’s how these things get combined.”

William Leu, a sophomore in UCSB’s Reserve Officer Training Corps, said that the research may benefit soldiers who return from combat and do not know they have PTSD.

“It is a great advancement and very well could be the next step in properly diagnosing and treating service members who have developed PTSD over the course of their military career. PTSD affects far too many military service members, and this will surely help them fight the battle that they unfortunately have to face when they return home,” Leu said.

Continuing research will focus on pinpointing what exact chemical changes take place and which ones can be useful to effectively diagnose PTSD.

A version of this story appeared on page 13 of Wednesday, January 8, 2014’s print edition of the Daily Nexus.