The health consequences of the first Gulf war

The lessons are general (and for many patients) rather than specific to that war

Two papers in this issue of the BMJ describe the long term health of British veterans of the 1990-1 Gulf war. In the article by Hotopf et al the King's Gulf war illnesses research group present another excellent study, this one indicating that 11 years after the conflict the Gulf veterans continue to experience considerably poorer health than control groups (p 1370).1 The article by Macfarlane et al examines the rate of malignancy in Gulf war veterans and shows that their overall rate of cancer is almost identical to those not deployed, even among those reporting exposure to potentially carcinogenic factors such as depleted uranium or pesticides (p 1373).2 These results are congruent with other data collected in both UK and US Gulf war veterans. Twelve years after the war, and after roughly $300m (£174m;€250m) has been spent on research, what do we know about the health of Gulf war veterans, in relation to what has actually happened to them?

Firstly, there is no evidence of excess malignancy, birth defects, or increased mortality associated with Gulf war deployment. However, and secondly, when those sent to the Gulf war are compared with military veterans of the same era who were not deployed to the Gulf, Gulf war veterans are two to three times more likely to have symptom complexes that include multifocal pain, fatigue, cognitive or memory problems, and psychological distress.3 4 Most of these individuals do not meet criteria for established psychiatric diagnosis, and in fact the rate of post-traumatic stress disorder in Gulf war era veterans was low compared with other wars.

Thirdly, many population based studies have shown that the same symptoms and clusters of symptoms that are observed in a substantial portion of Gulf war veterans are also common in the general population.3^–5 When individuals develop these symptom complexes in the general population they typically receive diagnoses of conditions such as fibromyalgia, chronic fatigue syndrome, irritable bowel syndrome, and tension and migraine headaches.

Fourthly, in addition to the relatively large proportion of deployed veterans (20-25%) who developed symptoms and syndromes found commonly in the population, there may be a much smaller proportion who developed a discrete neurological illness. For example, the rate of amyotrophic lateral sclerosis in Gulf war veterans may be double that in non-deployed controls (leading to an absolute risk of about 1:150 000 deployed troops).6 Even more controversial is the existence of a different and specific neurological disorder, reported in about 1 in 200 veterans in one population-based study.7 but not others, and not noted in case-control studies examining neural function.3 4 8

Why did this happen? Firstly, no specific environmental exposure, with the possible exception of vaccines given at the time of deployment, has been associated with the development of these symptom complexes. Secondly, since the Gulf war several authors have looked retrospectively at the health consequences of other UK or US wars. After nearly every such conflict, a substantial number of veterans develop chronic symptoms similar to those seen after the Gulf war. These syndromes are typically given different names and attributions (such as “shell shock,” “soldier's heart”) after each conflict.9 This recurring occurrence implies that there is a low likelihood that an exposure unique to the Gulf war was largely responsible for the excess symptoms seen in these veterans.

Thirdly, similar chronic symptoms are seen after catastrophic events other than war, such as terrorist attacks and natural or industrial disasters. Chronic somatic symptoms seem to be common sequelae when these catastrophic events last for a prolonged period or are accompanied by long term worry or fear.10

Fourthly, in the general population exposure to different types of “stress” can also lead to the development of these same symptom complexes. Examples of acknowledged triggers of fibromyalgia, chronic fatigue syndrome, or irritable bowel syndrome include certain types of infections, physical trauma, drugs, and emotional stress.

What are the lessons for practising clinicians? Together the data indicate that the excess morbidity seen in association with Gulf war deployment had little to do with any specific environmental exposure. War is incredibly stressful, and when most individuals are exposed to stressors such as physical or emotional trauma, infections, or other types of immune stimulation, drugs, or chemicals they develop somatic symptoms. Usually these symptoms improve after the stressor passes. But in some people these symptoms become chronic and, once established, are typically functionally disabling and in many cases refractory to treatment.

These chronic somatic symptoms and syndromes are common in routine clinical practice, so much so that most visits to primary care are for these problems. Research into some of the better studied conditions—for example, fibromyalgia, chronic fatigue, and irritable bowel syndrome—has provided insights into underlying mechanisms and appropriate treatments. For example, a hallmark of these syndromes is “central” pain, in which pain (whether it be myalgia, arthralgia, or visceral pain or discomfort) is not due to damage or inflammation of peripheral tissues, but to an underlying disturbance in the central processing of pain that can be quantified objectively by using newer functional imaging techniques.11 (Such findings also call into question some groups' interpretation of abnormal functional imaging results in Gulf war veterans as indicative of neural “damage.”12) Because the pain in these conditions is not due to damage or inflammation of peripheral tissues, these conditions respond poorly to non-steroidal anti-inflammatory drugs or opioids and instead are more responsive to low night time doses of tricyclic compounds or other centrally acting analgesics. In addition, treatments such as aerobic exercise and cognitive behavioural therapy have been found to be useful.

Make no mistake: ill Gulf war veterans have a very real illness. It is not likely to get better without specific interventions. But we don't serve these or other veterans well by focusing inordinate attention on the specific exposure(s) that may have been responsible for some rare cases of illness. As patients, they deserve far better: the medical and scientific communities need to stop belittling and trivialising them and their illnesses, as well as individuals in the general population who have the same symptom complexes.

Papers pp 1370, 1373