The postwar hospitalization experience of U.S. veterans of the Persian Gulf War.

BACKGROUND: Since the Persian Gulf War ended in 1991, many veterans of that conflict have reported diverse, unexplained symptoms. To evaluate the health of Gulf War veterans, we studied their postwar hospitalization experience and compared it with that of other military personnel serving at the same time who did not go to the Persian Gulf. METHODS: Using a retrospective cohort approach and data from Department of Defense hospitals, we studied hospitalizations of 547,076 veterans of the Gulf War who were serving in the Army, Navy, Marine Corps, and Air Force and 618,335 other veterans from the same era who did not serve in the Persian Gulf. Using multivariate logistic-regression models, we analyzed risk factors for hospitalization both overall and in 14 broad diagnostic categories during three periods from August 1991 through September 1993 (a total of 45 specific comparisons). RESULTS: After the war, the overall odds ratio for hospitalization of the Gulf War veterans was not higher than that of the other veterans, even after adjustment for selection effects related to deployment. In 16 of the 42 comparisons involving specific diagnoses, the risk of hospitalization among Gulf War veterans differed significantly from that among other veterans. Among these 16 comparisons, Gulf War veterans were at higher risk in 5: neoplasms (largely benign) during 1991, diseases of the genitourinary system during 1991, diseases of the blood and blood-forming organs (mostly forms of anemia) during 1992, and mental disorders during both 1992 and 1993. The differences were not consistent over time and could be accounted for by deferred care, postwar pregnancies, and postwar stress. CONCLUSIONS: During the two years after the Persian Gulf War, there was no excess of unexplained hospitalization among Americans who remained on active duty after serving in that conflict.

Daily asthma severity in relation to personal ozone exposure and outdoor fungal spores.

Epidemiologic investigations of ambient ozone (O3) effects on daily asthma status have not used personal O3 exposures and have often lacked well-characterized allergen exposures. To address this, we studied 12 asthmatic subjects aged 9 to 16 yr, who recorded daily asthma symptoms (functional levels 0 to 5) and as-needed inhaler use during September and October 1993 in San Diego, California, Outdoor aeroallergens, O3, and fine particle concentrations were measured at a central outdoor site, and personal 12-h daytime exposures to O3 were measured daily. Personal O3 differed greatly between subjects and was 27% of mean outdoor O3. In random-effects autoregression models controlling for weekend days and fungal spores, personal O3 was associated with asthma severity: for a 90th percentile increase in O3 (25 ppb), symptom scores increased by 25% (95% CI: 0 to 49%) and inhaler use increased by 26% (95% CI: 3 to 48%) over their averages. Outdoor 12-h O3, but not 1-h maximum O3, was associated with inhaler use (p < 0.03). Fungal spores were significantly associated with symptoms (scores increased by 0.1 to 0.3/1,000 spores/m3) and inhaler use (0.1 to 0.4 puffs/1,000 spores/m3) across speciated groups. Pollen and fine particles (low levels) were not associated with any outcomes. These findings illustrate that the epidemiologic importance of O3 and allergenic cofactors can be underestimated by failure to account for personal O3 and fungal exposures.