Positioned on a rolling Hawaiian hillside along the North Shore in Oahu, where the now-retired United States Army major was stationed, that tree was where Raciti said he planned to take his last breath. He planned to hang himself.

As a physician assistant, Raciti had been deployed five times, twice to Iraq, and mourned the suicide deaths of three medics who served with him. He suffered post-traumatic stress disorder and often fantasized about suicide.

"I did lose three medics after coming back from Iraq to suicide, which exasperated my PTSD, but mine is of survivor's guilt for the ones I could not save," Raciti said.

The US Department of Defense has continued to investigate what factors might influence a military member's risk of suicide attempt, and a new study suggests that previous suicide attempts in a particular unit of members can play a significant role.

Within Army units, the risk of suicide attempts among soldiers increases as the number of attempts made within the past year in their unit rises, according to the study, published in the journal JAMA Psychiatry on Wednesday.

In other words, the greater the number of previous suicide attempts in a unit, the greater the individual risk of a suicide attempt for a soldier in that unit, said Dr. Robert Ursano, professor of psychiatry and neuroscience and director of the Center for the Study of Traumatic Stress at the Department of Defense's Uniformed Services University.

Now, about 20% of suicide deaths in the United States each year are military veterans, according to the Military Health System

"This is an important part of trying to understand that story," Ursano said about the new study. "Although we often talk about the clustering of suicides and suicide attempts, it's rarely been able to be examined in an empirical way, using actual data."

The aftermath of a suicide attempt

The study involved data on 9,512 enlisted soldiers who attempted suicide between 2004 and 2009, documented in administrative and medical records.

among military personnel. The data came from the Army's Study to Assess Risk and Resilience in Servicemembers research project, or STARRS, the nation's largest study of mental health risk and resilienceamong military personnel.

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After analyzing the data, the researchers found that soldiers were more likely to attempt suicide if assigned to a unit with one or more previous suicide attempts in the past year, and that risk increased as the number of previous suicide attempts went up.

Among combat arms and other occupations, the risk of suicide attempt was about twice as likely among those in units with at least five previous suicide attempts in the past year versus units with none, the researchers found.

The risk for a unit with at least one suicide attempt in the past year was 18.2%, "indicating that, if the risk associated with units that had at least one past-year significant attempt could be reduced to those with no attempts, 18.2% of attempts would not occur," the researchers wrote in the study.

That increased risk remained significant even after adjusting for each soldier's sociodemographic factors, age, time in service, deployment status, occupation, and unit size, although the findings were particularly pronounced in smaller units, the researchers found.

"It actually aligns with some research that's been published in the past few years using smaller samples that aren't necessarily representative of the Army, but have similarly found that exposure to suicide is associated with increased risk of suicidal thoughts and behaviors in other service members," said Craig Bryan, a psychology professor and executive director of the National Center for Veterans Studies at the University of Utah, who was not involved in the new study.

The US Department of Veterans Affairs offers a crisis help line, local suicide prevention coordinators, and other resources to the general public.

However, Bryan said that the new study could help in developing improved approaches for what's known as postvention efforts -- an organized response after a suicide or suicide attempt -- specifically when a suicide attempt occurs in an Army unit.

"How we react to the event could on the one hand potentially mitigate or reduce risk of other suicidal behaviors or conversely, if you don't respond to situations like that very well, you could inadvertently increase risk amongst others," Bryan said.

"To be honest, postvention has not received nearly as much attention and as much focus as more traditional treatments and prevention methods," he said. "I think that's probably going to be the most important implication of this study, pushing forward that we should be doing a lot more and paying way more attention to how we effectively respond to suicide loss as well as suicide attempts within confined social groups."

Kim Ruocco, who was not involved in the new study, agreed that more attention should be turned to the importance of postvention protocols.

Ruocco serves as chief external relations officer for suicide prevention and postvention for the Tragedy Assistance Program for Survivors , a nonprofit that provides support, resources and referrals to those grieving a loved one who has served in the armed forces.

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"It's really important to implement postvention protocols after there's a suicide attempt," Ruocco said. "That would include balancing supporting the attempt survivor by maintaining a sense of belongingness and purpose within the unit while they are receiving the care they need, and identifying anything within the unit that increases risk," such as the deaths of many members in that unit or having a distrust of leadership in that unit.

"It is also important after an attempt to highlight resources, review risk and warning signs and encourage self care and support of peers," she said.

Encouraging conversations around suicide risk remain important for Ruocco, as she knows first-hand the dangers of remaining silent, she said.

She's the surviving widow of Marine Corps Major John Ruocco. Her late husband died by suicide in 2005 after not telling anyone about his mental health struggles, she said.

"I wish he knew just how valuable he was and how many people would have wanted to help him," she said. "Suicide is a very complicated event with lots of factors. ... I think what this study really shows us is that when there is a suicide attempt that it does increase risk for all those who are exposed to it."

'There's nothing worse than suffering in silence'

The new study still comes with several limitations, including that the data in the study were collected during wartime.

More research is needed to determine whether similar findings on suicide attempt risk would emerge among Army units not during a time of war, and what exactly those mechanisms of risk would be, Ursano said.

"Future research, which is now being developed with a continuation of this study, is to examine soldiers after 2009. So after the war has gone away, do we see the same effects? It's important to replicate the findings, to see if it's only amongst during times of high stress, meaning during war in the military," he said. "And we don't know the mechanisms here, and that's certainly an important area for future research."

Shawn Jones, Air Force and Army veteran and interim executive director for the nonprofit Stop Soldier Suicide , said that he would like to see more developmental studies on suicide risk.

"When you have a friend or loved one or battle buddy take their lives, it's devastating. You wonder why. You tend to hit the different levels of grief and try to process through them," Jones said.

"In the military culture, we're bred to be strong. We're the ones who help those who can't help themselves. So, there's that stigmatization, as well, that we don't need help. Everybody else needs help, but we never do," he said. "The military as a whole, we can do better as leaders, as to where that stigmatization lies, by helping soldiers go get help, whether it's psychotherapy or something else."

Marc Raciti, the retired US Army major, said that he kept his silent suffering a secret from those around him, including both his military family and biological family, because of that stigma.

'There is a crisis on our hands'

Sonja and Marc Raciti, a veteran couple, know first-hand how prevalent suicide is in the military.

It was Marc Raciti's now-wife, Sonja, who encouraged him to find help before he acted on his suicidal thoughts on that distant, ghostly hillside.

Sonja Raciti, 38, said that while dating Marc, she knew that he needed to get help.

"We worked at the civilian health clinic, just different departments, and we both fell madly in love with each other," said Sonja, an Army civilian psychologist, who met Marc while they were both assigned at the Schofield Barracks US Army installation in Hawaii.

"Right from, probably the third or the fourth date, it was pretty obvious that Marc had pretty severe PTSD," she said. "Every night he had nightmares and significant anxiety everyday."

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Text "741741"



TAPS National Military Survivor Helpline

800-959-TAPS (8277)

Following counseling and therapy, Marc said that his PTSD symptoms subsided and he wrote a book about his recovery, " I Just Want To See Trees: A Journey Through PTSD ."

"I remember telling Sonja if I can help one person with this book, my efforts would not have been in vain, and I did. I helped myself," Marc said.

With those dark days behind him, the 53-year-old veteran credits years of counseling and therapy for the joy-filled life he now lives in Phoenix, Arizona, with Sonja, their two children, and his PTSD service dog, Douglas.

Yet the memories of their military loved ones who died by suicide -- and Marc's own brush with death -- still haunt the couple to this day, they said.

"These are the guys that I mentored, these are the guys that I instructed, these are the guys that I taught how to be medics," Marc said about the lives lost. "It's devastating because these are folks we were pretty close to."

When it comes to military suicides, "there is a crisis on our hands," he said.

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Now, he hopes broader conversations around military suicide can help to change the stigma around mental health issues in the military.

"PTSD is a disease of avoidance. Everybody's heard of having a grandfather or someone who's been to war but doesn't like to talk about it. There's a reason for that, because you're drudging up very old, very painful memories," Marc said.

"Even to this day having PTSD or having any kind of mental syndrome, it's a sign of weakness in a lot of commands. You're just a weak person and that doesn't sit well within any military setting so that is a barrier to care when you look at it," he said. "This is a ... barrier to care that could result in a devastating result."