As U.S. troops continue to come home with invisible wounds, research -- including a big chunk being conducted in San Diego -- continues to change the understanding and treatment of post-traumatic stress disorder.
UC San Diego scientists recently showed that genes make some people more likely to get the condition, which is also known as PTSD. More than 90 other PTSD studies are underway at clinics for the U.S. Department of Veterans Affairs in this region.
Nearly 1,190,000 veterans obtained health services from the VA between Oct. 1, 2001 and March 31 of last year, according to the agency. Almost 379,000 of them were diagnosed with PTSD at some point.
Navy veteran Jordan Miller is one of those patients. He's also considered a PTSD success story at the VA hospital in La Jolla, which is helping to promote June as PTSD Awareness Month.
After completing 42 weeks of treatment as part of a research study that paired antidepressants with weekly "talk" therapy, he reports a night-and-day change in his PTSD symptoms.
"I don't think I'm 100 percent, and I don't think I ever will be. But I definitely think I'm well above 50 percent," said Miller, who served on Navy vessel-boarding teams in the Persian Gulf during three deployments. He left the military in 2014 after seven years of service.
"I'm not depressed anymore. I get a lot more sleep," the 29-year-old said.
The study that included Miller looked at how the antidepressant Zoloft interacts with exposure therapy, which asks PTSD sufferers to dissect their traumatic event over many sessions until it loses the power to cause anxiety.
Miller agreed to functional magnetic resonance imaging, or fMRI, scans that examined how his brain responded to treatment by mapping blood flow.
The former sailor said he didn't like the concept of group therapy. And the idea of being asked over and over how things "make him feel" was a deal-breaker. Exposure therapy felt like telling his story in an in-depth way, which was appealing.
At his doctor's suggestion, Miller also got a service dog, Teddy. The corgi, a working breed, gives him peace of mind that no one is sneaking up on the house at night while they sleep.
"Get the proper training," Miller suggests to veterans who might be shying away from treatment. "If group therapy isn't for them, then don't do it. If one-on-one is best, just do it."
PTSD is a relatively new field in medicine, acknowledged as a distinct disorder only 36 years ago.
Today's treatments, which experts said are based on evidence of success, have been around for 15 years, said Sonya Norman of the VA's National Center for PTSD.
And the past five years have been spent making them more known to the public, said Norman, who is also a psychologist at the San Diego VA.
The future is likely about examining the usefulness of alternative or "complementary" medicine -- such as meditation and accupuncture, which are popular but not yet totally proven to help alleviate PTSD -- and about refining treatment so it can be tailored to each person.
Genetics is emerging as a factor in PTSD research.
A UC San Diego study published last month in the Journal of the American Medical Association Psychiatry found that two gene markers are related to a higher risk of PTSD.
The study involved DNA samples from 13,000 U.S. Army troops and was done in conjunction with the Uniformed Services University and several other academic institutions.
"We knew before this study that there was a genetic basis for PTSD. Of course, that doesn't mean it is caused entirely by genes. What it means is that some people are more susceptible than others," said Dr. Murray Stein, a UC San Diego psychiatry professor who was a co-principal investigator on the study.
"We found there are some genetic variants that are associated with increased risk," he added.
A genetic variant found in African-American soldiers with PTSD was significant, the research discovered. The same gene is related to autoimmune and inflammatory disorders, including multiple sclerosis, Type 2 diabetes, Celiac disease and rheumatoid arthritis. In some soldiers with European heritage, a link was found on a different chromosome.
The increase in risk with these gene markers is relatively small, Stein said.
But if more research bears out the concept, the practical application could be to help shape who is chosen for combat and how they are prepared.
"The military, what they could do with that is if somebody is really high-risk, maybe this person is better in a support role," Stein said. "Or if we do need to put them into combat, what can we do to increase their resiliency before we send them into combat?"
Researchers at the San Diego VA are looking at how people with a certain gene might do better in one therapy than another.
"I'm hopeful that we are moving in that direction," Norman said about genetics and mental health.
"Other areas of medicine, such as cancer research, are much more advanced than mental health in terms of trying to use biological markers."