Health and Exposures of United Kingdom Gulf War
Veterans
Testimony to the Congress of the United States of
America
House Committee on Government Reform
January 24, 2002
Nicola Cherry, MD, PhD, FRCP
Professor and Director
Occupational Health Program
University of Alberta
Edmonton, AB Canada
Professor of Occupational and Environmental
Medicine
University of Manchester
United Kingdom
Following the return of UK Forces from the Gulf States in 1991, and subsequent reports of ill health, the UK Medical Research Council, with funding from the UK Ministry of Defense, invited proposals to examine whether UK Gulf War veterans had worse health than similar service personnel who had not been deployed, and to examine possible causes of such ill health. More than 30 research teams submitted proposals. Two were funded, one of morbidity and mortality in Armed Forces personnel (from the University of Manchester) and a second of possible effects on reproduction (from a team at the London School of Hygiene and Topical Medicine). A third UK study, from Kings College in London, was funded by the US Department of Defense. My testimony to this committee is based on findings from the study carried out at the University of Manchester, of which I was principal investigator.
The study proposed by the Manchester team was in two phases; the initial study was of a large random sample of men and women deployed to the Gulf and an equivalent sample of Armed Forces personnel who were medically fit but were not deployed. The second phase, to carry out detailed investigations of men and women who had been deployed to the Gulf and had become unwell, together with comparison groups, was initially approved but in the event funding was not available and this testimony is based only on the initial questionnaire study.
For this study, the UK Ministry of Defense identified, at our specification, three groups (or "cohorts") of service personnel each of just under 4,800 men and women. Two cohorts were of those who had been to the Gulf, the third of non-deployed men and women. We were able to contact more than 85% of those who were alive in the period of the study (December 1997 to September 1999). We thus have descriptions of the health, seven years after the Gulf War, of 12,191 men and women in the three cohorts, and of experiences in the Gulf from 8,085 of those who had served there in 1990-1991. Results from the analysis of self reported health of the men and women in these three cohorts, and of the relation between health and exposure in those who went to the Gulf were reported in two papers published in 20011,2. The comparison1 of the health of Gulf War veterans and non-deployed service personnel concluded that those who had been to the Gulf were more likely than those who did not to have symptoms suggestive of ill health, with some 14% of reported ill health attributable to deployment in the Gulf or to related events. An initial mortality study3 of all 53,462 UK service personnel who went to the Gulf and a comparison group of non-deployed service personnel showed only a very small increase in deaths in those who had been to the Gulf. However the period of follow-up (eight years after the War) was too short to detect any excess of mortality from diseases (such as cancer) with a long latency between exposure and death.
I understand that this Committee is particularly interested in the possibility of a relationship between exposures to chemicals or vaccines and subsequent ill health. Analyses of these data from the Manchester study have been published2. The information on current health (six to eight years after the conflict) and on exposures both came from questionnaires completed by the service men or women. The reports of ill health were given in response to a list of 95 complaints such as "waking with an attack of shortness of breath" or "difficulty concentrating". For each item the respondent was asked to indicate how seriously he or she had been troubled about this aspect of health during the past month. This approach was designed to give the best possible opportunity to detect a new syndrome, if one existed. The questions asked did not reflect pre-existing syndromes and cannot be used directly to answer research questions about, for example, post traumatic stress disorder or multiple chemical sensitivity. In addition to these 95 items, the respondents were asked to indicate whether they had experienced pain in the past month and if so to mark on a "manikin" (a cartoon body shape) where they had felt the pain. They were also asked if they had experienced numbness and tingling in the past month and to indicate, on a separate manikin, where this numbness and tingling had been; these latter data were used to identify people with a pattern of pain and tingling consistent with toxic polyneuropathy.
Exposures were reported quantitatively (number of days of exposure or number
of inoculations) and included exposures over which the service man or woman
had little or no control (for example: duration in the Gulf,
immunizations/vaccinations, living in accommodations sprayed with insecticides)
as well as those over which he or she had some option (for example: use of
insecticides on the skin). All of these exposures were self reported and,
in the study reported here, no attempt could be made to verify them. The
reports on exposures were however examined for consistency. Correlations
between exposures were found to be in the direction expected from known events
during the engagement, and were similar in the two Gulf War cohorts studied
in Manchester. Among those who went to the Gulf, 28% reported that they had
a record of the vaccinations they had received around the time of the deployment.
Careful analysis of the relation between reported exposures and symptoms,
having allowed for
all other exposures and other factors that might confuse the picture, found
that overall severity
of symptoms was related to the number of inoculations, number of days handling
pesticides and the days exposed to smoke from oil fires. When scores on factors
derived from the 95 symptoms were examined in relation to reported exposures,
increasing numbers of inoculations were associated, with increasing scores
on a factor heavily weighted with skin problems and muscle spasm. The number
of days handling pesticides was related to scores on a neurological factor,
but the score did not increase in direct relation to the number of days for
which pesticides had been handled. The handling of pesticides was also related
to a pattern of pain and tingling, recorded on a manikin, that was consistent
with a toxic neuropathy.
Studies that rely on self report for information on both exposures and health must be interpreted with caution. As discussed above, we had from the onset planned to do follow-up studies to establish whether or not those complaining of symptoms had objective signs, and to determine &endash; as best possible from Ministry of Defense records or elsewhere &endash; the likelihood of exposure. In the absence of funding, this part of the study could not be completed and this is a serious limitation in the usefulness of the data. However a putative relation between exposure and effect is established by the results of this questionnaire study.
Given the uncertainty, particularly in the UK Forces, about the type and
extent of pesticide use,
it would have been desirable to carry out investigations not only of exposures
and effect, but also of susceptibility. Several authors have suggested that
those affected by exposures in the Gulf may have a genetic make-up that would
make them more susceptible to organophosphates. In the unfunded second phase
of our proposal we included a plan to investigate whether those who became
ill had this susceptibility gene. We have meanwhile tested this hypothesis
in a separate group of exposed workers, sheep farmers in the United Kingdom
who have, over many years, used chemicals, particularly organophosphates,
to treat and prevent skin problems in sheep. The results of this study4,
support the hypothesis that organophosphates have contributed to the ill
health of farmers; those who are sick are more likely than those who have
remained well to have the genetic polymorphisms hypothesized to lead to greater
susceptibility. Given this result, it may be important, to design and conduct
a study among the UK Gulf War veterans who reported handling pesticides.
The aim of such a study would be to determine which veterans now have objective
signs of neurological damage and to examine the frequency of the genetic
polymorphism associated with greater susceptibility in these cases and in
a comparison group without signs
or symptoms. Even in the absence of objective measures of exposure, a greater
proportion of genetically susceptible individuals in those with neurological
damage would implicate organophosphates in causation.
References:
1. Cherry NM, Creed F, Silman A, Dunn G, Baxter D, Smedley J, Taylor S, Macfarlane GJ. Health and exposures of United Kingdom Gulf war veterans. Part I: The pattern and extent of ill health. Occupational and Environmental Medicine 2001; 58: 291-298.
2. Cherry NM, Creed F, Silman A, Dunn G, Baxter D, Smedley J, Taylor S, Macfarlane GJ. Health and exposures of United Kingdom Gulf war veterans. Part II: The relation of health to exposure. Occupational and Environmental Med 2001; 58: 299-306.
3. Macfarlane G, Thomas E, Cherry NM. Mortality of UK Gulf War Veterans. Lancet, 2000;356:17-21.
4. Cherry N, Mackness M, Durrington P, Povey A, Dippnall, M, Smith T, Mackness B. Paraoxonase (PON1) Polymorphisms in Farmers Attributing Ill Health to Sheep Dip. Lancet (in press)
# # #
Return to Witness Testimony List | Statements submitted for the Record