Wellness among US service members; the Millennium Cohort Study

Introduction: Recent military conflicts have resulted in the relocation of thousands of troops worldwide, where they encountered unique occupational experiences. While previous research has examined adverse health outcomes postdeployment in military populations, little research has focused on wellness or positive health outcomes following deployment.

Methods: A prospective study was conducted among members of the Millennium Cohort Study who deployed in support of the operations in Iraq and Afghanistan. Dimensions of wellness were measured using standardized instruments that assess physical health, mental health, and stress. Predictors of postdeployment wellness were assessed using ordinal logistic regression analysis, while adjusting for predeployment wellness and other covariates.

Results: Of the 10,228 study participants, 9.2% were categorized as “most well”, 78.7% were categorized as “moderately well”, and 12.2% were categorized as “least well” postdeployment. In multivariable analysis, military and deployment predictors of postdeployment wellness included serving in another branch besides the Army, no combat experience, and occupation (combat specialist). Cumulative deployment time and dwell time were not associated with post-deployment wellness. Modifiable predeployment factors significantly associated with being well postdeployment included screening negative for mental disorders, not being obese, and not smoking or binge-eating.

Conclusion: Experiencing combat was associated with being less well; however, those trained in combat appeared to be protected. While not all factors predicting wellness are modifiable, targeted predeployment interventions could focus on modifiable behaviors in order to improve postdeployment wellness. An understanding of the exposures associated with postdeployment wellness may guide readiness and ensure a well force.