Gulf war illness – better, worse, or just the same? A Cohort Study
Hotopf M, David AS, Hull L et al.;
Commented by , 28 Jan 2004
Background
A worsening of psychological and physical health has been established in Gulf war veterans, however, the longer term course of morbidity remains unclear.
Purpose
To compare the prevalence of various health outcomes over time and between military cohorts.
Methods
Stage 2 of an occupational cohort study via postal survey. In 1997 (stage 1), the authors studied a large random sample of British armed forces personnel (N=8196), consisting of three cohorts
- members serving in the 1991 Gulf war
- UN peacekeeping members in Bosnia 1992-1997
- army personnel in 1991 not deployed to the Gulf (“Era cohort”)
A random stratified sample from stage 1 (N=3305) was selected. Three mailings were sent during 2002. Main outcome measures:
- self-reported fatigue (Chalder Fatigue Scale)psychological distress (12-item General Health Questionnaire)
- physical functioning and health perception (SF-36)
- a list of 50 common symptoms, from which “post-traumatic stress reaction” (PTSD) was defined.
Mean differences between stage 1 and 2 scores were presented using 95% confidence intervals.
Results
The response rate was 71.6% (N=2370). Non-responders had poorer health at stage 1 on the SF-36. Compared with the other cohorts, Gulf veterans were more symptomatic on all outcomes at stages 1 and 2. They experienced only modest reductions in the prevalence of
- fatigue (48.8% stage 1, 43.4% stage 2)
- psychological distress (40.0% stage 1, 37.1% stage 2)
- PTSD (12.4% stage 1, 10.8% stage 2)
For controls, there were no significant prevalence differences on these outcomes over time. All three cohorts experienced a slight worsening of physical functioning (non-significant for “Era”).
Discussion
More than 10 years later, Gulf veterans continue to experience poorer psychological and physical health than controls. For all cohorts, there is stability in the prevalence of the symptom complexes studied over time. Study limitations include self-report data, subject to reporting bias. The poorer health of non-participants at stage 1 also raises the possibility of having underestimated the prevalence rates.
The strength of the study is in the broadening of health outcomes beyond established diagnostic syndromes, such as PTSD. In devoting our research and resources to this extreme end of the illness spectrum, we would fail to capture and understand the much larger group with functionally disabling stress response syndromes (1).
The psychological and physical symptom complexes experienced by military personnel in conflict is not unique to this group. They follow other catastrophic events, such as terrorist attacks, natural disasters and rape. Similar symptom clusters are also commonly found in the general population, receiving diagnoses of chronic fatigue syndrome, fibromyalgia and irritable bowel syndrome.
Most visits to primary care physicians are in fact for chronic somatic symptoms, a large portion of which represent “medically unexplained symptoms.” The unifying link amongst all these groups being exposure to “stress.”
The association between stress and physiological and psychological health has long been observed, with a resurgence following the pioneering work of Hans Selye (2). Yet, as Daniel Clauw, professor of Rheumatology, cautions in his editorial (3) to this paper, clinicians and scientists remain preoccupied in their search for alternate specific exposures; such as elusive environmental toxins in the Gulf, or reinforcing medical investigations and treatments (e.g. narcotics, benzodiazepines) for somatoform presentations.
This reductionistic approach to these common stress response syndromes trivializes these complex presentations, promotes iatrogenic illness and thwarts the development of appropriate prevention and intervention strategies informed by our developing understanding of psychological and physiological sequlelae of stress.
References
1. Horowitz MJ. Stress Response Syndromes (2nd Ed). New Jersey: Jason Aronson Inc., 1986
2. Selye H. The Physiology and Pathology of Exposure to Stress; a Treatise Based on the Concepts of the General-Adaptation Syndrome and the Diseases of Adaptation. Montreal: Acta Incorporated Medical Publishers, 1950
3. Clauw D. The health consequences of the first gulf war. BMJ 2003; 327; 1357-1358