June 27, 2010:  The growing effort to treat PTSD (post-traumatic stress disorder) has benefited from the large amount of information collected from troops who have experienced a lot of combat. Some of the first discoveries were that symptoms were related to changes in brain chemistry. In particular, PTSD patients had lower levels of neurosteroids in their brains than those who were normal. Increasing neurosteroid levels has reduced PTSD symptoms. But as more PTSD sufferers reported their combat experience in detail, other patterns began to emerge. It was discovered that men who had killed enemy troops up close, were more likely to suffer from PTSD. This was hinted at from research done with World War II PTSD patients. But new sensor technology makes it possible to measure the degree to which someone has PTSD, and relate that to their combat experiences. Another item known from World War II, was the relationship to being close to a lot of explosions, and the likelihood of developing PTSD. Actually, this was known during World War II, when PTSD was called "shell shock."

In separate research, it was discovered that patients suffering from PTSD, along with other forms of mental distress (substance abuse, depression, chronic pain) had different brain images (provided by CT scans) than those with just PTSD. Neither of these discoveries is going to cure PTSD, but they are examples of how new technology (how to easily measure neurosteroids in the brain and cheaper and easier brain scans) has made it possible to isolate the physical factors operating in PTSD patients. That kind of incremental success, results in better treatments for PTSD.

The research is also showing that PTSD is a distinct form of mental distress. For example, research turned up the fact those who had killed someone in combat, were 40 percent more likely to show symptoms of PTSD, or similar symptoms found in those who suffered concussions from roadside bombs. Thus it is becoming clear that there are several different conditions here, all with similar PTSD symptoms, but not with similar effects on the brain. Each strain of PTSD will require a different type of cure. Finding these cures is increasingly important, since better diagnostic capabilities has made it possible to more frequently, and accurately, diagnose PTSD.

And then there is the fact that the current fighting has produced a very different pattern of casualties. Better tactics, training and equipment has reduced physical casualties by two thirds (compared to earlier wars). This has also allowed troops to remain in combat for much longer than before. Never before has the U.S. had so many troops who have experienced so many days of combat, and that translates into more PTSD.

In the past (Vietnam, World War II) casualties were several times higher, but combat was not as prolonged. Thus few troops lasted 200 or more days in combat. During World War II, it was found that 200 days was the average combat exposure a soldier suffered before starting to experience debilitating PTSD. But now the military, and the VA, are finding that some combat events can trigger more, or less, PTSD. Roadside bombs have, for example, caused soldiers problems because the blast can inflict mild concussion on troops who are not otherwise injured. Years later, those mini-concussions can cause mental problems.

Earlier patterns of combat were different. For example, during World War II, the bulk of the Allied troops in Europe went in after June 6, 1944. The fighting in Europe ended eleven months later. In the Pacific, the fighting tended to be episodic. A few months of combat, followed by many months of preparing for the next island invasion or battle. In Vietnam, not a lot of people went back for multiple tours, and those who did spend a year with a combat unit, spent less time in combat than they would in Iraq. Even during Vietnam, it was noted that many of those who were in combat for 200 or more days, did get a little punchy.

In Iraq and Afghanistan, army combat troops often get 200 days of combat in one 12 month tour, which is more than their grandfathers got during all of World War II. And some troops are returning for a third tour in Iraq or Afghanistan. The army has found ways to avoid the onset of PTSD (better accommodations, email contact with home, prompt treatment for PTSD), but many troops are headed for uncharted territory, and an unprecedented amount of time in combat. Thus the research, and new programs to spot PTSD as early as possible.

Things have calmed down since the peak year of combat, 2007, when 904 Americans died in Iraq (and 117 in Afghanistan). In that year, there were about 14,000 American PTSD casualties, while there were less than half as many troops who were physically wounded.

It's not the prospect of getting killed that causes the stress, but rather the constant state of alertness required to survive in combat. Death and injury is always a factor in military life. Over the last 25 years, the U.S. Army has always lost one or two thousand dead each year to accidents, disease and suicide (in that order). That meant about two troops per thousand died each year. In Iraq, the risk of getting killed or wounded in combat was 2-3 percent for a one year tour, in the worst years.

Since World War II, other factors for PTSD have been discovered. Israel noted, after the 1982 war in Lebanon, that reservists were more sensitive to the aftereffects of combat. The Lebanon conflict used a larger number (than previous wars) of older reserve troops, who tended to be more prone to coming down with stress disorders. This was probably due to the fact the full time soldiers are constantly conditioned to deal with stress. While this is often referred, often derisively, as "military discipline," it has been known for thousands of years that such practices reduce stress and panic during combat. Apparently it reduces the chances of coming down with stress problems as well.  Thus the new programs to spot stress related problems, as early as possible, and also develop new treatments. The stress angle has been more intensively studied in Iraq than in any previous war. Naturally, the more you look, the more you find.