Serving in a war carries with it the possibility of being wounded or dying in combat. But new research suggests that veterans who served in Vietnam also had also higher death rates after returning home than did veterans who served tours of duty elsewhere.

Service in Vietnam exposed soldiers to a variety of potential health risks, ranging from psychological stress to infectious diseases and chemicals. The Centers for Disease Control and Prevention (CDC) launched the Vietnam Experience Study (VES) to gauge the health effects of military service there, but the initial study ended in 1983. For the new report, a team led by Tegan K. Catlin Boehmer of the CDC followed more than 18,000 veterans through 2000, resulting in more than 30 years of health data. The researchers report in the latest issue of the Archives of Internal Medicine that during the first five years after discharge, Vietnam veterans experienced a death rate 7 percent higher than that of other veterans. For the remainder of the study period, however, there was no statistically significant difference in the death rates between the two groups.

The higher death rate among Vietnam veterans resulted from an increase in external causes of death, the team found. The authors note that their findings corroborate those of previous research linking combat exposure with elevated illicit drug use, and post-traumatic stress disorder with traumatic deaths, including unintentional poisonings.