Combat, PTSD and Smoking Trajectory in a Cohort of Male Australian Army Vietnam Veterans.

Background: Whether trauma exposure itself or consequent posttraumatic stress disorder (PTSD) is primarily responsible for smoking and failure to quit remains unclear. Methods: A cohort of male Australian Vietnam veterans (N = 388) was interviewed twice, 22 and 36 years after their return to Australia using standardized psychiatric diagnostic and health interviews and assessment of combat exposure.The smoking trajectory over time revealed a spectrum of outcomes (never smoked, early quitters, late quitters, and continuing smokers). Analysis used multivariate statistics to assess the relative contributions of combat trauma exposure and PTSD while controlling for potential confounders. Results: The trajectory of smoking over time revealed that 21.9% of veterans had never smoked, 45.1% had quit smoking by the time of wave 1, 16.2% were current smokers at wave 1 who had quit by the time of wave 2, 2.8% were late adopters who were current smokers, and 13.9% were continuing smokers. Smoking was associated in single-predictor models with demographics, intelligence, combat exposure, PTSD symptom clusters and diagnosis, and alcohol disorders. Multivariate analysis revealed that PTSD, combat, and intelligence were related to the smoking spectrum but, after adding demographics and other Axis I psychiatric diagnoses, only combat remained significant. No PTSD symptom cluster uniquely predicted smoking status. Conclusions: The results suggest that trauma exposure in the form of military combat may be a more robust predictor of smoking status over time than PTSD. It may be stress itself, rather than poststress disorder, that is more germane to smoking and failure to quit.