Recent study reveals that after the attack on September 11, 2001, New York City children suffer from anxiety or depression and are more succeptable to further mental stress if there are any future tragedies.

A survey of more than 8,000 children from the 4th to 12th grades found 29 percent suffered from one or more of six anxiety or depressive disorders six months after the hijacked plane attacks on the World Trade Center in which nearly 2,800 people died.

The most common disorders were agoraphobia, a fear of public places; separation anxiety, a fear of being apart from parents or family; and post-traumatic stress disorder, which is normally associated with soldiers after combat.

The report from Columbia University Medical Center and the New York State Psychiatric Institute said a key finding was that children previously exposed to violence or other disastors prior to the hijacked plane attacks were more vulnerable to post-traumatic stress afterward.

Children who had a close relative killed or injured in the Sept. 11th attacks were more likely to experience persistent mental trauma than those who had direct experience of the attacks, such as children who attended schools near the World Trade Center towers, the report said.

Study author Christina Hoven wrote in the Archives of General Psychiatry that "This somewhat surprising finding (about children near the site of the attack) may possibly be explained by a combination of factors, such as worldwide attention to their situation, increased social support, and the fact that students in the Ground Zero area schools were the recipients of significant mental health intervention immediately after Sept. 11, 2001."

Because of the study's findings, study officials believe that intervention programs aimed to ease the effects of the prior trauma caused by September 11th are vital in the New York City schools.