Volume 4, Number 4—December 1998
Hospitalizations After the Persian Gulf War
To the Editor: Knoke et al., Naval Health Research Center, San Diego, California, published two articles on military hospitalizations in Persian Gulf War veterans, the most recent in Emerging Infectious Diseases (1,2).
Although the titles of both articles indicated general hospitalizations, Knoke et al. studied just military hospitalizations among selected, mostly healthy, active-duty Persian Gulf War veterans enlisted as of 1994. They compared military hospitalizations of active-duty Gulf War veterans (cases) with military hospitalizations of active-duty era veterans not in the Persian Gulf between 1990 and 1991 (controls). "Healthy warrior" effects would have predicted low military hospitalization rates for both cases and control populations (3), but both were high.
The studies were "restricted to active-duty personnel" hospitalized in military facilities because active-duty personnel were "rarely hospitalized outside of DoD facilities" (1). However, of 150 surgical procedures, mostly intestinal and skin biopsies, performed on 85 sick active-duty and reservist Persian Gulf veterans from Pennsylvania between 1991 and 1995, more than one third, 58 (39%), were performed in private facilities (4). Most of the federal procedures were done in Veterans Administration (VA), not military, hospitals. Many active-duty, sick Persian Gulf veterans in Pennsylvania, Texas, and California deliberately avoided military, and some VA, hospitals between 1991 and 1997 because of concerns about competence, convenience, confidentiality, and career opportunities during this era of downsizing and closing of military bases (3,5).
In addition, Knoke et al. excluded at least five groups of sick veterans from their limited case studies: 1) those treated in VA and private hospitals, 2) those from the Reserves and National Guard, 3) those who retired early largely because of illness, 4) those who consented to long military hospitalizations within the DoD Comprehensive Clinical Evaluation Program (CCEP) for Gulf War Veterans, and 5) those who had obstetric complications after returning home from the Gulf War. Thus, many sick veterans were excluded from the case studies.
If we hypothesize that one or more new infectious agents like Leishmania tropica, Brucella species, Bacillus anthracis, Mycoplasma fermentens (incognitus), Coxiella burnetti, or obscure fungi or molds might be involved, comprehensive research studies in the future would do better to include all workers from the Arabian desert, reservists as well as active-duty personnel.
Few Gulf veterans with Gulf-related illnesses were welcomed by military hospitals and about half of 452 Persian Gulf veterans surveyed by the U.S. General Accounting Office sought health care outside the VA for health problems they believed were related to service in the Persian Gulf (5). An alternative interpretation of Knoke's hospitalization study might be that admitting officers in military facilities prevented sick Persian Gulf War veterans from obtaining medical care within their facilities.
Not only were the case populations studied unusual; recent workers and travelers to the Middle East were not excluded from the control population. "Nondeployed" controls included recently deployed Persian Gulf military personnel as long as nondeployed personnel worked in the Gulf after 1991. Some of those late-deployed Persian Gulf workers also fell ill with the same illnesses as veterans deployed between August 1990 and 1991. Illnesses from late Persian Gulf deployments might explain excess hospitalizations seen in nondeployed controls. All late-deployed personnel from the Middle East should also have been excluded from the nondeployed control population.
Finally, medical ICD-9 diagnoses, while interesting, were incomplete and nonspecific. Medical diagnoses common to Gulf veterans should have been listed in addition to unexplained illnesses. Knoke's condensed diagnostic list, like patient charts we have seen from DoD hospitalizations, may have failed to capture common clinical and laboratory abnormalities seen in many sick Gulf veterans, including (but are not limited to) ulcerative colitis, Crohn colitis, inflammatory bowel disease, intestinal bleeding due to inflammatory colonic polyps, skin acne, nodules, plaques, psoriasiform skin rashes, nose ulcers, nose bleeds, leukocytosis, neutropenia, elevated alanine transaminase (SGPT/ALT) liver enzymes, hepatosplenomegaly, thrombocytopenia, nephrolithiasis (kidney stones), and fevers of unknown origin (4,6). In addition, more than one unexplained illness category should have been tabulated per patient, because "Gulf War Syndrome" is a multisystem illness (4,6-9).
More research is needed on hospitalizations in addition to deaths and new diseases found in Persian Gulf War veterans (3). Civilian scientists and physicians must collaborate closely with other diverse federal and nonprofit organizations to study Gulf War illnesses objectively (5,9). The health problems seen in Gulf War veterans may be part of a new complex of emerging desert-associated illnesses (9-14).
- Gray GC, Coate BD, Anderson CM, Kang HK, Berg SW, Wignall RS, The postwar hospitalization experience of U.S. Persian Gulf War veterans compared with other veterans of the same era. N Engl J Med. 1996;335:1505–13.
- Knoke JD, Gray GC. Hospitalizations for unexplained illnesses among U.S. veterans of the Persian Gulf War. Emerg Infect Dis. 1998;4:211–9.
- Haley RW. Bias from the "healthy warrior effect" and unequal follow-up in three government studies of health effects of the Gulf War. Am J Epidemiol. 1998;148:315–23.
- Murray-Leisure KA, Sees J, Zangwill B, Suguitan E, Legaspi C, Bagheri S, Mucha P, Brinser E, Kimber R, Kurban R, Greene W. Mucocutaneous-intestinal-rheumatic Desert Syndrome (MIRDS): Incubation & histopathology findings. Abstract K 48, American Society for Microbiology, ICAAC, Sept. 18, 1995.
- U.S. General Accounting Office. Gulf War Illnesses: Improved Monitoring of Clinical Progress and Reexamination of Research Emphasis are Needed. GAO/NSIAD-97-163. June 1997.
- Sostek MB, Jackson S, Linevsky JK, Schimmel EM, Fincke BG. High prevalence of chronic gastrointestinal syndromes in a National Guard unit of Persian Gulf Veterans. Am J Gastroenterol. 1996;91:2494–7.
- Centers for Disease Control. MMWR Morb Mortal Wkly Rep. 1995;44:443–7.Unexplained illness among Persian Gulf War veterans in an Air National Guard unit: Preliminary report, Aug 1990-March 1995.
- Fukada K, Nisenbaum R, Stewart G, Thompson WW, Robin L, Washko R, Chronic multisystem illnesses affecting Air Force veterans of the Gulf War. JAMA. 1998;280:981–8.
- Nicolson G, Nicolson N. Gulf War illnesses. Med Confl Surviv. 1998;14:156–65.
- Magill AJ, Grogl M, Gasser RA, Wellington S, Oster CN. Viscerotropic leishmaniasis caused by Leishmania tropica in soldiers returning from Operation Desert Storm. N Engl J Med. 1993;328:1383–7.
- Magill AJ, Grogl M, Johnson SC, Gasser RA. Visceral infection due to Leishmania tropica in a veteran of Operation Desert Storm who presented two years after leaving Saudi Arabia. Clin Infect Dis. 1994;19:805–6.
- Ferrante MA, Dolan MJ. Q Fever meningoencephalitis in a soldier returning from the Persian Gulf War. Clin Infect Dis. 1993;16:489–96.
- Seaman J, Mercer AJ, Sondorp E. Epidemic of visceral Leishmaniasis in western upper Nile, southern Sudan: Course and impact from 1984 to 1994. Int J Epidemiol. 1996;25:862–71.
- Zilinskas RA. Iraq's biological weapons. JAMA. 1997;278:418–24.