Post-traumatic Stress Disorder is common in refugees in Western countries and could be up to 10 times higher than in the general population, researchers said on Friday.

“Our review suggests that at least several tens of thousands of current refugees in western countries have post-traumatic stress disorder (PTSD),” Dr. Mina Fazel, of the University of Oxford in England, said in a report in The Lancet medical journal.

PTSD, which has also been called shell-shock or battle fatigue syndrome, can lead to other psychiatric problems such as depression.

It usually appears within three months of the traumatic event and can cause flashbacks, irritability, difficulty concentrating, nightmares and panic attacks. The disorder could also be a risk factor for substance abuse and suicide.

About 13 million people are classified as refugees worldwide. An estimated 9 million live in developing countries and about half of them are children.

The researchers, whose findings are based on 20 surveys of 6,743 adult refugees from seven countries between 1996-2002, estimate that one in 20 refugees has major depression and about one in 25 has a generalised Anxiety disorder.

In a commentary on the research, Michael Hollifield, of the University of Louisville in Kentucky, said only about 3-4 million refugees in the west with psychiatric problems have access to medical care.

“If we do not have the capacity to prevent war, we have a collective responsibility to better understand and treat its psychiatric, medical and social consequences,” he said.