Abstract
Introduction It is evident that an association between smoking and post-traumatic stress disorder (PTSD) exists, but research is lacking in establishing the directionality of the relationship. Aims and Methods We used longitudinal data from waves I (2001-2002) and II (2004-2005) of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). Individuals with nicotine dependence (ND) were matched to individuals without ND using propensity score matching to estimate the risk of developing PTSD after trauma. We also matched smokers (with or without ND) to lifetime nonsmokers to estimate their risk of developing PTSD after trauma. Lastly, we conducted a mediation analysis on the effect of ND severity on PTSD symptoms. Results Individuals with ND (n = 1514) were more likely to develop PTSD (odds ratio: 1.59; 95% confidence interval: 1.09-2.32; p = .017) compared with individuals without ND (n = 6047). Smokers (regardless of ND status) (n = 2335) compared with nonsmokers (n = 5226) had no significant effect on risk of PTSD (p = .26). Withdrawal was found to be a mediator of the effect of ND severity on PTSD symptoms. Conclusions ND, but not smoking status, increases a smoker's risk of developing PTSD. This provides information that could aid in preventive strategies for individuals with ND who are exposed to trauma. Implications This study provides evidence in a national representative sample of adults in the United States that ND may increase one's risk of developing PTSD after exposure to trauma. It also shows the directionality of the association between smoking and PTSD. Lastly, it demonstrates that withdrawal may be the link to the association between ND and PTSD. We hope that with these findings, preventative strategies are put in place for smokers who are dependent and are exposed to trauma, such that they do not develop PTSD.