Can differences in the brain predict better treatment of post-war trauma?
The casualties of war are too great to count. Limbs lost. Lives ended. Loved ones left behind.
But many men and women who return home after serving their country with bravery suffer wounds that no one can see. The rate of post-traumatic stress disorder (PTSD) among soldiers who have served in Afghanistan and Iraq is estimated at 13 to 18 percent, and many consider that a conservative number. PTSD results in persistent and frightening memories of a terrifying emotional or physical event that make it difficult to hold a job or sustain a relationship. The disorder is also associated with higher rates of alcohol and drug abuse, as well as suicide.
Help is available in the form of medication and psychotherapy, but half of the veterans with combat-related PTSD don’t get better after taking medication for eight weeks. Jack Nitschke, a psychiatry professor in the UW School of Medicine and Public Health, wants to know how brains differ at the start of treatment for those who get better and those who don’t.
“What are the brain mechanisms that are involved in this disorder? We don’t have a good idea of that, so there’s just a lot of work that needs to be done,” says Nitschke, who is studying brain differences, hoping to pinpoint the most effective treatment for individual soldiers.
Nitschke, who also treats patients with severe anxiety disorders, researches these differences at the Waisman Laboratory for Brain Imaging and Behavior. He decided that he could no longer ignore the crisis facing many returning servicemen and women, nor the fact that soldiers redeployed a third or fourth time are at an even greater risk of developing PTSD.
“You have really a tremendous amount of suffering, and that’s how I became interested in this,” says Nitschke, who hasn’t studied the condition before. To tackle the problem, he is combining his efforts with Eileen Ahearn and Tracey Smith, clinical UW psychiatry faculty practicing at William S. Middleton Memorial Veterans Hospital in Madison.
Very few studies have been done on how to treat combat-related PTSD, Ahearn says. “People spend a lot of time waiting for treatment to take effect, and we’re not good at predicting which treatment is going to benefit which patient,” she says. “[If] we can understand what’s happening at the brain level … it would save a lot of distress and time for patients. They could be directed to a particular type of treatment.”
Hospital staff inform patients about available studies, and the researchers say there is no shortage of enthusiasm among veterans for helping fellow veterans. “We’ve actually had people who agree to try medication in part because they heard that it might help another veteran,” she says. “There is an unparalleled sense of altruism and camaraderie amongst veterans. They want to help each other.”
Each participant in the study has a brain MRI done before and after beginning medication or psychotherapy for PTSD, allowing Nitschke to look for differences between the brains of people who have been exposed to combat and have the disorder, and those who don’t develop any symptoms.
Nitschke has used this method to guide treatment for patients with generalized anxiety disorder. In one recent study, he found one medication was more effective for some patients with the disorder by looking at how their brains processed anxiety. He’s hoping to do the same thing with PTSD, noting, “If we can find out what brain signatures there are prior to treatment, that can predict treatment outcome.”
Half of the PTSD study participants receive anti-depressant medication while the other half undergo psychotherapy. After an eight-week period, Nitschke looks at brain differences between people who respond to treatment or medication and those who do not. His findings could help doctors decide — based on what a patient’s brain looks like — whether medication or therapy is the best course of treatment.
“Part of the problem with PTSD is that there’s very high avoidance. … People try to avoid thinking about these terrible experiences, but the avoidance perpetuates the PTSD symptoms,” Ahearn says. “So teaching people not to avoid the trauma, but actually revisiting the trauma in a protected, therapeutic setting helps to diminish the symptoms overall and to provide relief.”
Veterans hospital psychologists employ cognitive-processing therapy, a treatment specifically designed to address PTSD. Patients write about the traumatic event in detail and work with a therapist to reconcile the beliefs they held before it happened — such as, “I am safe” — with what they experienced in combat.
“How veterans interpret the trauma affects subsequent reactions to their experience,” Smith says. “Studies have found that trauma survivors who experience conflict between their prior beliefs and the trauma experience are more likely to have more severe reactions and more difficulty recovering.”
After Nitschke finishes collecting scans from 120 subjects, which should take about three years, he hopes to launch studies to test the effectiveness of therapies based on any brain differences he identifies. Ultimately, he wants to find a way for all soldiers with PTSD to get better after a first attempt at treatment.
“You go over, and you experience all of this awful stuff. You come back, and you get a little celebration at first, [but] then you end up suffering — for some people, years and years and years. … And a lot of that stuff, I think, really could be eradicated,” he says. “Some of the treatments we have already are doing that effectively, and for those who we’re not reaching, we need to find out how to reach them.”
For more information, visit http://www.waisman.wisc.edu/nitschkelab.
Published in the Spring 2010 issue
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