Wednesday’s Fort Hood shooting — the third major shooting on a military base in four years — spawned questions about the impact of mental illness and war injuries on the suspected shooter, identified by officials as Army Spec. Ivan Lopez, a veteran of the Iraq war.

Lopez, who served a four-month tour in Iraq in 2011, was being treated for depression and anxiety, had reported a traumatic brain injury and was undergoing tests for post-traumatic stress syndrome, according to Army officials. These conditions were found among about three in 10 returning veterans in a 2008 Rand Corporation study sponsored by the Department of Defense.

A new Washington Post-Kaiser Family Foundation poll found that many returning Iraq and Afghanistan service members face mental health problems that are connected with anger issues:

  • 31 percent say their mental and emotional health is worse than before going to war
  • 36 percent of those with “worse” mental health say they often experiences outbursts of anger (among all Iraq/Afghan veterans, just 15 percent say this)
  • 32 percent with “worse” mental health say their mental and emotional health needs are not being met well (compared with 13 percent of all veterans)

These data warrant major caveats: Mental health problems — even angry outbursts — do not always provoke violent actions. The precise reason behind the shooting at Fort Hood remains unknown, and at best represents an extreme manifestation of a mental health problem.

The flip side to the above data also is also important: A clear majority of veterans who say they’re mentally “worse off” from the wars believe their health needs are now being met.

In 2012, more U.S. service members committed suicide than were killed in combat, according to a Washington Post tally, and a study by the Department of Veterans Affairs found the suicide rate among veterans had grown about 20 percent from 2007 to 2010. The Department of Veterans Affairs has increased spending to combat the issue, as the number of veterans seeking mental health care has risen dramatically.

The Post-Kaiser poll found that 51 percent of Iraq and Afghanistan vets personally know a service member who has attempted or committed suicide.

The survey was conducted Aug. 1 to Dec. 15, 2013, among a random national sample of 819 active duty military and veterans who served in the Iraq or Afghanistan wars. Interviews were conducted on conventional and cellular phones; the overall margin of sampling error is plus or minus five percentage points.

Read more from the Post-Kaiser Iraq and Afghanistan veterans survey: