Traumatic brain injuries sustained by more than 200,000 U.S. troops may be fueling the military’s suicide crisis, according to a letter co-signed by 53 congressional members who are seeking additional data to investigate the new theory.

In the letter, sent Tuesday to Defense Secretary Chuck Hagel and Veterans Affairs Secretary Eric Shinseki, the lawmakers urged both agencies to provide Congress with a raft of figures, including the number of Iraq and Afghanistan service members and veterans who committed suicide or tried to end their lives after being brain injured by the detonation of an improvised explosive device — “the weapon of choice” in both wars.

“Evidence has suggested that blast injuries, including but not limited to those causing damage to vision or hearing, can have a severe psychological impact ... that can play a major contributing role in suicides,” read the bi-partisan letter.

Between November 2011 and October 2012, there were more than 15,000 IED attacks against U.S. service members in Afghanistan, and 58 percent of all coalition casualties during that span were caused by the hidden bombs, the letter states.

At least three veterans groups, including the Blinded Veterans Association, are backing the congressional push to — as the letter to DOD and VA states — “get a better understanding of the connection between blast injuries and suicide.”

“I’ve talked to a lot of neurologists, military neurosurgeons and trauma surgeons who have all started to ponder if the IEDs that have caused the TBIs are the real cause of the suicides, versus the traditional approach that suicides are all caused by the psychological stresses of combat,” said Thomas Zampieri, head of government relations for the Blinded Veterans Association.

“Let’s collect more information and maybe the epidemiologists will find a way to unlock some of this mystery: Are military suicides actually more related to the brain injuries? I think there may be a big connection,” added Zampieri, who served as a Vietnam-era Army medic. “As the numbers of TBIs go up, the numbers of suicides continue to go up.”

The portion of U.S. service members who sustained TBIs increased each year from 2001 to 2011 — with a total of 266,810 brain injuries diagnosed in American troops between 2000 and 2012, according to the Defense and Veterans Brain Injury Center, part of the DOD. More than 80 percent of those injuries were not deployment-related cases, with many occurring amid crashes of privately owned cars and military vehicles. 

Army soldiers account for the vast majority of diagnosed TBI cases, and those injuries range from “mild” (a concussion) to “severe.” Within the Army, the suicide rate among active-duty members has risen from 9 per 100,000 in 2001 to nearly 23 per 100,000 in 2011, according to the American Foundation for Suicide Prevention.

During that same span, according to the DOD’s brain injury center, the number of annual TBI diagnoses among American troops has ballooned from 11,580 in 2001 to 32,609 in 2011 — an increase of 182 percent.

“What is significant is that we are looking at a potential paradigm shift of significant proportion if the link between low-level TBI from IEDs emerges,” said retired Army Col. Bob Morris, founder of the Global Campaign against IEDs.

“The current automatic approach is to connect everything to Post Traumatic Stress Disorder and look at it all as psychological when it may be a physiological,” Morris added. 

The lawmakers additionally asked the DOD and VA to supply "specific autopsy findings (of service members or veterans) potentially indicative of prior TBI." The members said they want to know whether such post-mortems found "chronic traumatic encephalopathy", which has been detected in the brains of a number of NFL players who recently committed suicide. 

Numerous Iraq and Afghanistan veterans have been diagnosed with both TBIs and PTSD, as well as with hearing loss — the most common disability among the men and women who served in those wars. 

"There is no higher priority for VA than the mental health and well-being of our courageous men and women who have served the nation," said a VA spokesman, responding to the congressional letter. "Under the leadership of Secretary Shinseki, VA has made significant progress in providing increased access to mental health care services and strengthening our suicide prevention efforts, but there is more work to do. VA is committed to providing all Veterans the care and benefits they have earned and deserve.”

A Pentagon spokeswoman said Hagel "responds directly to correspondence received" and that it would inappropriate for her comment on the letter. 

Rep. Dan Benishek, R-Mich., a surgeon who worked at a VA medical center for 20 years, led the effort to collect congressional signatures for the letter to Hagel and Shinseki.

“Far too many of our veterans and military personnel have taken their own life after bravely serving our nation. Frankly, it’s tragic and unacceptable,” Benishek said in a statement Tuesday. “I am hopeful that by working together we can make sure our guys and gals in the military and the VA have the support they need to recover from the damaging psychological effects of war.”

"There is particular evidence linking suicide to those wounded by IEDs," added Rep. Richard Hanna, R-N.Y. "It is my hope that through additional research we will be able to identify and reverse this painful trend. One suicide is too many and we should do all we can to address this as quickly as possible."

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Natalie Cass / WireImage via Getty Images file

Michael Matthews, left, and director Kirby Dick attend "The Invisible War" premiere after party at Innovation Gallery last month in Park City, Utah. Matthews has blasted the filmmaker for abandoning male victims.

Two male rape survivors who appear in "The Invisible War," an Oscar-nominated documentary about military sexual assaults, are criticizing the movie's brief focus on male victims as an ironic snub — and, in a fiery diatribe, one of the film's characters says the director "should be ashamed and embarrassed."

"We're being abandoned by (director) Kirby Dick. The guys feel betrayed," said Michael Matthews, a 20-year Air Force veteran who, in the movie, tells of his 1974 gang rape by three other airmen. The publicity campaign hawking the film — and its Academy Award candidacy — includes a website that shows the faces of six female victims of military sexual assault, and no male survivors of that crime, as well as formal screenings to which only female victims have been asked to attend, Matthews said.

"What the (bleep) is that about? They don't list any of the men on the website. He's making millions of dollars but he's not bringing any of the men to any these appearances all over the country like he's bringing the women," Matthews told NBC News. "I appreciate them putting us in the movie but, now, the men are not being represented at all. He has turned his back on us. And the movie, some of it, is hurting us."

Navy veteran Brian Lewis — who was raped by a male, senior non-commissioned officer in 2000 and then discharged from the Navy shortly after reporting the attack — said he and Matthews are disturbed that the film's fleeting attention on male victims, both on screen and in promotional tactics, symbolizes the way male sex-assault survivors have been marginalized by society and by some lawmakers investigating the issue of rapes within the armed forces. Lewis has a 10-second soundbite in the documentary.

"'The Invisible War' runs for just under two hours (99 minutes) and men received probably a lot less than five minutes. How frustrating would that be?" asked Lewis, 33, who serves on the board of Protect Our Defenders, an advocacy group for service members who have been sexually assaulted by fellow troops.

"You can't really address the problem of military sexual trauma until you include the 56 percent of the victims — the men — and they are being ignored right now," Lewis said. 

Dick told NBC News he empathizes with both men, and agrees that male rape victims are being "kept in the shadows" by their country, and said Matthews — who had the harshest words for the director — "has been phenomenal in terms of what he contributed to the film, and in terms of his continuing to push the issue forward both for women and especially for men.

"When people come forward to talk about this, there's not just a pain in that moment but there are nightmares afterward for most of these survivors. It's a very painful thing and they talk about it again and again and again. That, really, is true courage. We owe these men a great deal of gratitude for coming forward. These are the true whistle-blowers," Dick said. "I accept the fact that there are certain frustrations. But that is nothing in comparison to what Michael has accomplished and is accomplishing. And if it takes a little emotion to get that out, I'm 100 percent behind it."

Dick acknowledged that he and the movie's female producer purposely devoted the bulk of the screen time to the stories of military women who have been assaulted by men. (He added that the perception he or the producers are earning millions of dollars is "simply not the case.")

"In terms of making the film, we felt the entry point in this discussion was more women being assaulted because we felt it was a discussion that people would start to have," Dick said. "Our essential goal here is to have the military continue to change its policy (on investigating rape reports and disciplining predators) so that all men and women are protected in the military ... We felt that once the country started putting pressure on the military to make these changes, if and when the military does make changes, those will apply to men just as they will women. So we kind of felt women would get the discussion going and push the military to make the change for everyone."

'Nobody wants to talk about it'
According to Nate Galbreath, senior executive adviser to the U.S. Defense Department's Sexual Assault Prevention and Response Office (SAPRO), a 2010 survey found that 4.4 percent of active-duty women and 0.9 percent of active-duty men "indicated that they experienced some form of unwanted sexual contact in the year prior to being surveyed."

That math equates to about 19,000 sex-offense victims per year inside the armed forces, including about 10,000 men and 9,000 women.

"There's a lot of disappointment in the male survivor community that this keeps being talked about as a 'women's issue,' and it's not," said Susan Burke, a Washington, D.C.-based attorney who is spearheading a series of nationwide lawsuits meant to reform the manner in which the military prosecutes rape and sexual assault. She represents male and female military-rape victims.

"From interviewing hundreds of rape and sexual assault survivors, both male and female, there's a persistent pattern by the military in essentially even refusing to accept the allegation, where the chain of command basically says, 'We are not going to even report this.' And that is much more prevalent with the male victims," Burke said. "What I've seen time and time again: a male who comes forward to report rape and sexual assault is accused of being a homosexual."

But according to Dr. Loree Sutton, a psychiatrist and retired Army brigadier general, rapes are not about sex but are instead fueled by aggression and domination. The crime is almost an animalistic demonstration that the predator "owns" the prey. Many male-on-male rapes in the military are group attacks. Some involve drugging the victims.

"It's not about gay sex. Typically the predators are heterosexual men who have this need to assert power, control and dominance," Sutton said. "It's similar to the dynamics of what happens with incest — those family bonds, the trust, the loyalty. I mean, in the military, loyalty becomes this huge factor and that is so difficult for men and women to sort out."

She believes that many male victims never report sex assaults committed against them by other male service members often because "in society, people just don't know how to relate to them," and the confusion such survivors face among family or friends — after they eventually open up about their rapes — "can re-open very deep wounds," Sutton said. "It's almost unspeakable."

Matthews, 58, kept the attack against him secret for nearly 30 years before he finally told his wife in 2001. Today, living in New Mexico, has launched an idea for a movie — now in post-production editing — that examines only men's stories of military rape and how those assaults changed those men forever. The title: "Justice Denied."

"These men feel ostracized in our society. Nobody wants to talk about the truth — that most of the rapes in the military (victimize) men. Nobody wants to talk about it," Matthews said.

"How long can they be ignored?"

Related: 

• Civil Rights Commission urged to order audit of military sex-assault cases
• Reported sex assaults leap 23 percent at US military academies
• Sex-assault victims in military say brass often ignore pleas for justice

The highest number of U.S. Marines will exit Afghanistan in August compared to any other month in 2012 as a large exodus of American troops continues, U.S. Marine Corps Maj. General David Berger said today in a phone interview from Afghanistan. 

In the country's southern Helmand province — a swath once so volatile that an additional 10,000 Marines were massed there three years ago — the Marine contingent will continue to shrink drastically over the next three weeks, said Berger, commanding general of the 1st Marine Division (Forward). 

"We’re not going to give out detailed numbers on where we’ll end up, but it’s a cut of about two-thirds of the size of strength here (compared to) a year ago, and it will be somewhere between 7,000 and 10,000 Marines when we finish up," Berger said. 

"There will be more Marines and soldiers and equipment moving in August than any other month. All the ones that are deploying from Afghanistan on the Marine Corps side, they’re going back to their home bases on the East Coast, on the West Coast."

Adek Berry / AFP - Getty Images

US Marines from Kilo Company of the 3rd Battalion 8th Marines Regiment patrol in Garmser, Helmand Province on June 29.

The pullout of U.S. forces this year is expected to reach 23,000 total troops. The NATO coalition's combat mission in Afghanistan is scheduled to finish at the end of 2014. Last year, President Obama ordered 10,000 U.S. troops out of Afghanistan.

While shifting more control to Afghan security forces and Afghan police, Berger said he has seen "amazing progress last year into this year," first, in terms of the Afghans' military development and, second, in their available fighting equipment and ability to man those tools.

"The third part is confidence — confidence in themselves and the people’s confidence in them," Berger said, "Each week, they’re more confident in what they can do in the field. The police are more confident. The people can begin to trust them in a way that was really challenging a year and a half ago.

"Now, I think the people (here) see the Afghan security forces as ... really the public face of their government. So the more they see of this, the more confidence people have that the Afghan government can protect them, can take care of them. So from where we sit, it’s absolutely going in the right direction."

However, Berger acknowledged that the massive swarm of Marines headed home — particularly those who will be retiring from the military and trying to enroll in college or land civilian jobs — will only begin that long transitionary phase after they return to the United States. 

"It happens after they leave country for the most part," Berger said. "While they’re over here, they’re pretty much occupied by the reason they were sent here. 

"But those who make the decision to move on into their civilian life, when they get back they’ll go into a formal program that first will lay out all the benefits coming to them. There’s a second part that helps them prepare for everything from doing a resume to doing an interview, to narrowing a field of choice, to getting an education.

"If you had gone through that process of separating from the service to entering the civilian world four or five years ago, you would be very much surprised by the program that’s in place right now — in a good way," Berger said. 

Related: Obama announces 'reverse bootcamp' for veterans

Still, with tens of thousands of service members headed home, that influx will only further tax a huge backlog of disability claims already clogging the U.S. Department of Veterans Affairs and it could potentially exacerbate a high college drop-out rate and sluggish job hiring now plaguing many veterans of the wars in Iraq and Afghanistan. 

Slideshow: Afghanistan: Nation at a crossroads

Ahmad Jamshid / AP

More than ten years after the beginning of the war, Afghanistan faces external pressure to reform as well as ongoing internal conflicts.

Launch slideshow

Retired sergeant Thomas Maretich, who in June earned a medical retirement from the Army, said he knows of many service members still in Afghanistan — and some still in Iraq - who "are not letting go those jobs" because they worry that what awaits them in America is simply the unemployment line. 

"They’re afraid. This is the worst possible time for anybody to look for work let alone anybody who has been wounded and has the cards stacked up against them," said Maretich, who was wounded by a car bomb in Iraq in 2009 and has had trouble finding work in his current city, Colorado Springs. "They could retire (from the military) at 20 ...  They just don't see a job in the civilian world that is safe and pays the same."

What's more, "they don't have enough mental health (help available) now at the VA. Many soldiers will need medical care for problems with their neck, back, or knees and the system that is already trying to catch up will be paralyzed again," he said. "Mix in budget cuts and what a mess we will have."

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