Increased psychological distress among Danish Gulf War veterans--without evidence for a neurotoxic background. The Danish Gulf War Study.

INTRODUCTION Compared with controls, up to six years after their return, Danish Gulf War veterans have a significantly higher prevalence of self-reported neuropsychological symptoms, potentially as a result of neurotoxic exposure during deployment. We tested the hypotheses that: 1) GW veterans would perform less well than controls using a computerized neuromotor test battery; and that 2) GW veterans have a psychological profile different from that of controls. MATERIAL AND METHODS A cross-sectional study of 686 subjects who had been deployed in the Persian Gulf within the period August 2, 1990 until December 31, 1997; the control group comprised 231 subjects matched according to age, gender and profession. All participants underwent clinical and paraclinical examinations, along with a neuromotor test battery (CATSYS Test System) and a psychological health status questionnaire, the SCL-90-R rating scale. RESULTS No differences were found between GW veterans and controls with respect to lifestyle and cohabitational characteristics. Differences between the two groups with respect to neuromotor function were very small. Within the GW veteran group, stratified according to clustering of neuropsychological symptoms, and stratified according to SCL-90-R score, no trends were found suggesting reduced motor function with increasing symptoms. Of nine dimensions constructed on the basis of the SCL-90-R items, six were significantly associated with being a Gulf War veteran. Statistically, the strongest associations were found for ratings of the obsessive-compulsive dimension and of the depression dimension. No associations were found with respect to phobic anxiety, paranoid ideation, and psychoticism. INTERPRETATION The increased psychological distress found among Danish GW veterans seemed rather due to a mentally distressing environment than to neurotoxic exposure.