Tobacco dependence is associated with increased risk for multi-morbid clustering of posttraumatic stress disorder, depressive disorder, and pain among post-9/11 deployed veterans.

RATIONALE: Tobacco use is highly prevalent among individuals with posttraumatic stress disorder (PTSD), depressive disorders, and pain. Research has revealed pairwise relationships among these conditions but has not examined more complex relationships that may influence symptom severity, chronicity, and treatment outcome.
OBJECTIVE: To examine the clustering of current PTSD, depressive disorders, and clinically significant pain according to current tobacco use and dependence among post-9/11 deployed veterans.
METHODS: Logistic regression was used to examine the clustering of these conditions in relationship to current tobacco use/dependence, while adjusting for age and total combat exposure, in 343 post-9/11 deployed veterans enrolled in the Translational Research Center for TBI and Stress Disorders (TRACTS) cohort (Mage = 32.1 + 8.3 years; 38% current tobacco use; 25% low and 12% moderate/high tobacco dependence).
RESULTS: A three-way clustering of PTSD, depressive disorder, and pain was more likely than any single or pairwise combination of these conditions in moderate/high tobacco-dependent veterans compared to tobacco non-users (adjusted ORs = 3.50 to 4.18). This multi-morbidity cluster also was associated with increased PTSD severity.
CONCLUSIONS: Moderate to high dependence on tobacco is associated with substantially increased clustering of PTSD, depression, and clinically significant pain in veterans. Research examining synergistic interactions among these conditions, biological vulnerabilities shared among them, and the direct impact of tobacco use on the pathophysiology of PTSD, depression, and pain is needed. The results of such work may spur development of more effective integrated treatments to reduce the negative impact of these multi-morbid conditions on veterans' wellbeing and long-term health.