Living through the trauma of war seems to increase the risk of developing asthma, suggests research published ahead of print in the Journal of Epidemiology and Community Health.
Those who are most traumatised are twice as likely to develop the condition as those who are least traumatised by their experiences of war, the research suggests.
The authors base their findings on a random sample of just over 2000 Kuwaiti civilians who endured the Iraqi invasion and seven month occupation of their country in 1990, and were aged between 50 and 69 at the time.
Between 2003 and 2005, these civilians were quizzed about their health, including a diagnosis of asthma after liberation; experiences of the war; and lifestyle factors, such as smoking and weight.
The researchers acknowledge that assessing the impact of war related trauma is difficult, because some of the stressors may be unique to a particular situation and the circumstances can be complex. So they used a validated questionnaire (Harvard Trauma Questionnaire), supplemented with face to face interviews to capture individual experiences.
Around one in six men (16%) and one in five women (20%) did not experience trauma during the war. But two thirds of the men (68%) and over half of the women (59%) feared for their lives.
Among the 413 participants with a low war related stress (Rasch) score, only one reported having been assaulted; three said they had been arrested; and 28 had had their house searched. None had witnessed torture, rape, or executions.
But among the 517 with a high stress score, around one in 10 (12%) had been arrested; one in six (16%) had been assaulted; and more than half (57%) had witnessed torture. New cases of asthma after liberation had been diagnosed in 6.6% of the men and just under one in 10 (9.7%) of the women.
There was a direct correlation between the amount of trauma experienced and the risk of developing asthma, even after adjusting for factors likely to influence the results, including exposure to air pollution as a result of burning oil fires.
Those who had experienced the most trauma were twice as likely to develop asthma as those who had been the least traumatised.
These findings are backed up by a growing body of evidence, which links the physiological impact of stress on the body and inflammatory conditions, such as asthma, say the authors.
"Although prior research has documented the significant and persistent psychological toll of war, these findings implicated even broader health effects," they conclude.
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