Longitudinal assessment of mental disorders, smoking, and hazardous drinking among a population-based cohort of US service members.

Objectives: Combat exposure is known to increase the risk for mental disorders; however, less is known about the temporal relationship between mental disorders and alcohol misuse or smoking. To better understand these interrelationships, this study investigated mental disorders in association with hazardous drinking and cigarette smoking.

Methods: Using data from a large population-based military cohort, standardized instruments were used to screen for posttraumatic stress disorder, depression, panic, and other anxiety syndromes. Self-reported use of cigarettes and hazardous drinking was also assessed. Subjects were classified as having "new-onset," "persistent," or "resolved" mental disorders and health risk behaviors on the basis of screening results from baseline to follow-up (n = 50,028). Multivariable logistic regression models were used to investigate temporal patterns between the development of mental disorders and the uptake of smoking or hazardous drinking.

Results: The strongest associations of new-onset mental disorders were among those who newly reported smoking or hazardous drinking (odds ratio [OR], 1.82; 95% confidence interval [CI], 1.28-2.59 and OR, 2.49; 95% CI, 2.15-2.89, respectively), even after adjustment for combat deployment experience. In addition, persistent smokers and hazardous drinkers had elevated odds for developing a mental disorder at follow-up.

Conclusions: This study demonstrates a positive association between the onset of mental disorders with the uptake of smoking and hazardous drinking and the likelihood that multiple temporal sequence patterns exist to explain the relationship between mental disorders and hazardous drinking and smoking. Clinical approaches to mitigate deployment-related mental disorders should include alcohol and tobacco-related assessments and interventions.