Influence of PTSD symptom clusters on smoking status among help-seeking Iraq and Afghanistan veterans.

Introduction: Despite the strong association between smoking and posttraumatic stress disorder (PTSD), mechanisms influencing smoking in this population remain unclear. Previous smoking research has largely examined PTSD as a homogenous syndrome despite the fact that PTSD is composed of four distinct symptom clusters (i.e., reexperiencing, effortful avoidance, emotional numbing, and hyperarousal). Examination of the relationship between smoking and PTSD symptom clusters may increase understanding of mechanisms influencing comorbidity between smoking and PTSD. The goals of the present study were to (a) examine the influence of overall PTSD symptom severity on likelihood of smoking and smoking heaviness and (b) examine the influence of each PTSD symptom cluster on smoking.

Methods: Participants (N = 439) were Operation Iraqi Freedom/Operation Enduring Freedom combat veterans referred to VA mental health services.

Results: Multinomial logistic regression was chosen to accommodate a three-level outcome, in which the likelihood of being a nonsmoker was compared with (a) light smoking (1-9 cigarettes/day), (b) moderate smoking (10-19 cigarettes/day), and (c) heavy smoking (> or =20 cigarettes/day). Results showed that veterans with higher levels of overall PTSD symptomatology were more likely to endorse heavy smoking (Wald = 4.56, p = .03, odds ratio [OR] = 1.65). Veterans endorsing high levels of emotional numbing were also more likely to endorse heavy smoking (Wald = 6.49, p = .01, OR = 1.81); all other PTSD symptom clusters were unrelated to smoking.

Discussion: The association between emotional numbing and heavy daily smoking suggests that veterans with PTSD may smoke to overcome emotional blunting following trauma exposure.