Cigarette smoking and military deployment: Prospective evaluation of smoking among a large population-based US military cohort

Background Occupational stress related to serving in the military has been reported as a strong predictor for cigarette smoking and nicotine dependence. Stress of military deployment may compound military occupational stress and manifest in coping behaviors such as cigarette smoking.

Objective To describe new and resumed smoking among nonsmokers and change in daily smoking among smokers, in relation to military deployment.

Methods The Millennium Cohort Study is a 21-year longitudinal study launched in 2001. Participants in the current study (N = 48 378) submitted baseline data (July 2001-June 2003) before the current military conflicts, and follow-up data (June 2004-January 2006) on health measures. New or resumed smoking was identified among baseline nonsmokers; increased or decreased daily smoking was identified among baseline smokers.

Results Among never-smokers, smoking initiation was identified in 1.3% of nondeployed and 2.3% of deployers. Among past smokers, smoking resumption occurred in 28.7% of nondeployed and 39.6% of deployers. Smoking increased 43.8% among nondeployed and 55.6% among deployers. Past smokers were 35 times more likely to smoke at follow-up than never-smokers (odds ratio, 35.3; 95% confidence interval, 31.8-39.3). Other deployment factors independently associated with postdeployment smoking initiation included deploying for longer than 9 months, multiple deployments, and combat exposures. Among those who smoked at baseline, deployment was not associated with changes in daily amount smoked.

Conclusions Military deployment is associated with smoking initiation, particularly among those with prolonged or multiple deployments, or combat exposures. The strongest predictor for smoking initiation was having been a smoker in the past.