Combat Deployments Associated with New-Onset Coronary Heart Disease among Young U.S. Service Members and Veterans
BACKGROUND:
Heart disease is the leading cause of death in the U.S.. Stress is a contributing factor for coronary heart disease (CHD) and is present during combat; however, the role of specific deployment experiences and PTSD on the incidence of newly reported CHD is not well-defined, especially among service members returning from deployments in Iraq and Afghanistan. Because the number of combat-exposed Veterans continues to increase, as well as those with PTSD symptoms, understanding the impact of these experiences on CHD is important. This prospective cohort study sought to determine whether specific deployment experiences and PTSD symptoms are associated with newly reported CHD among a young cohort (n=60,025; mean age = 34 years at baseline) of U.S. military personnel (active duty) from all service branches who had participated in the Millennium Cohort Study during 2001-2008. Investigators assessed PTSD symptoms, combat experiences, health status (i.e., presence of diabetes, depression, hypertension), health behaviors (i.e., smoking, drinking), and demographics. Newly reported CHD was defined as the self-reported absence of a diagnosis of CHD, heart attack, or angina at or before the baseline survey – and the presence of CHD or heart attack at follow-up. [Angina was not included at follow-up due to the possibility of misclassification of non-cardiac causes of chest pain.]
FINDINGS:
- Combat deployments were associated with new-onset CHD among young U.S. service members and Veterans. After adjusting for all covariates, service members who reported combat experiences had nearly twice the odds of having a diagnosis code for new-onset CHD than service members wthout combat exposure. This suggests that experiences of intense stress may increase the risk for CHD over a relatively short period among young adults.
- Screening positive for PTSD symptoms was associated with self-reported CHD prior to – but not after adjusting for depression and anxiety, and was not associated with a new diagnosis of CHD.
- At baseline, service members with newly reported CHD were proportionally more likely to be male, older, married, in the Reserves/National Guard or Army, obese, a smoker, a heavy drinker, inactive in regards to physical activity, and to have diabetes, hypertension, and depression.
LIMITATIONS:
- Although investigators adjusted for multiple risk factors for CHD, data for serum cholesterol, diet, and hereditary factors other than race/ethnicity were not available.
- Misclassification of covariates and potential residual confounding may have occurred given the self-reported nature of some covariates (e.g., weight) and lack of quantiative measurements (e.g., BP).
- The follow-up period may have been too short for the development of clinically symptomatic CHD in this younger population; future follow-up of this cohort is recommended.
- Models that adjusted for depression and anxiety, conditions that are highly comorbid with PTSD, may have masked the effect of PTSD on CHD.
AUTHOR/FUNDING INFORMATION:
Dr. Ulmer is supported by an HSR&D Career Development Award.
Crum-Cianflone N, Bagnell M, Schaller E, Boyko E, Smith B, Maynard C, Ulmer C, Vernalis M, and Smith T. Impact of Combat Deployment and Post-Traumatic Stress Disorder on Newly Reported Coronary Heart Disease among U.S. Active Duty and Reserve Forces. Circulation. March 11, 2014;e-pub ahead of print.
