“I came home and just dealt with it and went back to work,” he recalls. “As a leader of Marines, I didn’t want to show any weakness. And as a police officer, I didn’t want to lose my job,” he explains. Miller returned to Iraq in 2007, where he suffered another head injury when the vehicle he was riding in drove into a crater. He was tossed from his seat and slammed his head against the ceiling of the vehicle. Again, he tried to ignore his worsening symptoms. “I was hypervigilant and had quick mood swings and a violent temper. I wasn’t sleeping. My demeanor and my attitude were changing for the worse,” Miller says. In 2010, after contemplating suicide, he finally sought help and was diagnosed with a mild to moderate traumatic brain injury (TBI) and severe post-traumatic stress disorder (PTSD). He learned that some of his TBI-symptoms, including his migraines and memory loss, were triggers for his mood swings and other behaviors. Miller was prescribed multiple medications, began therapy, and learned various coping techniques. He now gives speeches around the country about his experiences as part of the Wounded Warrior Project. The residual effects of his injuries are never going to go away, he acknowledges, “but you learn how to manage it and live with it.”

Sorting Out TBI and PTSD Symptoms

PTSD was officially adopted by the American Psychiatric Association in 1980, based on research of Vietnam War veterans, to describe the intense symptoms — flashbacks, nightmares, and outbursts of anger — some people develop after witnessing or experiencing a traumatic event. Since then, studies of returning veterans from Iraq and Afghanistan have found that veterans who sustained concussions during their tours of duty had a higher risk of developing PTSD, as noted the 2016 book Translational Research in Traumatic Brain Injury. But the dual diagnosis isn’t just found in military personnel: The National Center for PTSD notes that PTSD can also develop in noncombat settings following traumatic events, such as assault. “It’s normal to have stress reactions following something traumatic,” says Lisa Moy Martin, RN, chief of clinical translation for the Defense and Veterans Brain Injury Center in Silver Spring, Maryland. In the usual process of integrating trauma into that person’s life experience, these reactions should subside, she explains. If they don’t, they may indicate PTSD. The National Institute of Mental Health notes that PTSD symptoms usually emerge within three months of the traumatic incident. The diagnosis is made using a clinically administered PTSD Checklist, coupled with a professional evaluation and assessment. Because many symptoms of PTSD are similar to those of a concussion, making the distinction may rely on context, Moy Martin explains. For example, sleep issues due to nightmares would point to PTSD, but if someone’s having racing thoughts that interfere with sleep, that would more likely be TBI-related, she notes. Symptoms common to both PTSD and TBIs include:

Difficulty sleepingDifficulty concentratingDepressionAngerAnxiety

One recent study found that certain factors predicted whether people who’d been diagnosed with a TBI later developed PTSD. The study, published in January 2017 in the Journal of Neurotrauma, focused on adult civilians who’d been to the emergency department and been diagnosed with a TBI. They were evaluated for PTSD symptoms six months later, which is when TBI tends to peak, as noted in the study. Close to 27 percent of participants were found to have PTSD, and nearly all of the people in this group were still experiencing TBI-related symptoms at the six-month mark. They were also more likely to have pre-existing mental health conditions, such as anxiety or depression, compared with those who hadn’t developed PTSD. As the reality of ongoing limitations and the slowness of recovering sinks in, it can heighten anxiety or depression, explains lead author Juliet Haarbauer-Krupa, PhD, a senior health scientist on the TBI team at the CDC’s Injury Center in Atlanta. “It’s only when you try to go back to work or school that you may really start noticing this,” she says. The study also showed that victims of assault, which generally involves more psychological trauma compared with other TBI causes, such as falling or being in a car crash, were more likely to be in this group. To Dr. Haarbauer-Krupa, the study’s findings provide an opportunity to identify many of these factors at the time the concussion is first diagnosed. “I hope that physicians will ask patients about their pre-injury history, and that patients are willing to tell them,” she says. “If you have pre-existing issues, you should be followed up on, because you may have PTSD and a longer recovery.” RELATED: How Trauma in the Military Can Lead to PTSD

Moving Beyond Symptom-Based Diagnosis

As part of the quest to differentiate between the two conditions, researchers are exploring additional diagnostic methods besides reported and observed symptoms. In one recent study, published in August 2016 in the International Journal of Psychophysiology, researchers found that electroencephalograms (EEGs) showed promise in differentiating between concussions and PTSD. The study participants were all active-duty military personnel or veterans who had been exposed to a blast while deployed in Iraq or Afghanistan. The EEGs, which measure the brain’s electrical activity using electrodes placed on the scalp, showed different brain wave patterns in participants with concussions than in those with PTSD, and also found that these brain wave patterns involved different areas of the brain. Concussions were associated with an increase in low-frequency brain wave forms. These become more active when someone is in a state of low arousal, such as being asleep, according to the study’s coauthor, William C. Walker, MD, a professor of physical medicine and rehabilitation specializing in brain injury at Virginia Commonwealth University and Hunter Holmes McGuire Veterans Affairs Medical Center in Richmond. By contrast, PTSD was associated with decreased low-frequency brain waves. Essentially, an underaroused state was associated with concussions, while a hyperaroused state was associated with PTSD. These results still need to be confirmed more broadly, but could potentially be used to tailor treatments based on the EEG profile, Dr. Walker says. As an example, someone who has a concussion might benefit from a stimulant medication, but this wouldn’t be helpful for someone with PTSD, whose brain is already in a more aroused state. “We know that someone who’s had a TBI is oftentimes at risk for PTSD,” Walker says. “But because the two can have similar neurobehavioral symptoms, it can be difficult to distinguish between them based on symptoms alone.”

Treatment and Recovery From PTSD and TBI

In some cases, people who have been diagnosed with PTSD following a TBI may be prescribed medication to address specific symptoms, such as selective serotonin reuptake inhibitors (SSRIs), which can be helpful in treating depression and anxiety, notes Moy Martin. Nonmedication alternatives, including cognitive processing therapy (CPT) and prolonged exposure (PE) therapy, have also both been found useful in treating TBIs and PTSD, according to the National Center for PTSD. Moy Martin also recommends seeking out support groups. “They’re a wonderful resource, not just for the person but for their family members and friends,” she says. “They help people realize that many of these symptoms aren’t unusual and that there are ways to cope and live with them.” Many VA centers offer support groups, as do the Wounded Warrior Project and PINK Concussions. More information about PTSD (including TBIs and PTSD) is available on the National Center for PTSD’s site. RELATED: What Are the Best Treatments and Therapies for PTSD?