Determinants of long-term neuropsychological symptoms. The Danish Gulf War Study

Compared with controls, up to six years after their return, Danish Gulf War Veterans have a significantly higher prevalence of self-reported neuropsychological symptoms. Independent associations are found for concentration or memory problems, repeated fits of headache, balance disturbances or fits of dizziness, abnormal fatigue not caused by physical activity, and problems sleeping all night. We investigated whether psychosocial, physical, chemical or biological exposures were associated with these symptoms.

This study is a prevalence study using retrospective data on exposure. Some 686 subjects who had been deployed in the Persian Gulf within the period August 2 1990 until December 31 1997 were included; the control group comprised 257 subjects matched according to age, gender and profession. All participants underwent clinical and paraclinical examinations, and were interviewed by a physician based on a completed questionnaire.

A clustering of three to five of the above symptoms were found in 21.4% of Gulf War Veterans vs. 6.2% in controls, p < 0.001. Psychosocial and physico-chemical factors were strongly associated with neuropsychological symptoms, and a significant interaction of the two was found, p < 0.001.

Although the results of this study are based on self-report the factors identified seem plausible. It may be impossible even in peace-keeping missions to avoid hostile events. However, the results also suggest that psychosocial work conditions known to be important in civilian life, and also environmental factors, should be improved to minimize the risk of long-term neuropsychological symptoms.