Millennium Cohort Study (United States)

The Millennium Cohort Study is an ongoing longitudinal cohort study headquartered at the Naval Health Research Center in San Diego, California and designed to evaluate any long-term health effects of military service, including deployments.

[1] It is the largest population-based prospective health project in US military history,[2][3][4] currently collecting data on over 200,000 enrolled participants.

Investigators that conduct the Millennium Cohort Study include uniformed and non-uniformed scientists from the Army,[5] Navy,[6] Air Force,[7] Department of Veterans Affairs[8] and academic institutions.

Prospective data analyses are underway to assess health outcomes including Suicide,[15] Posttraumatic stress disorder,[16][17] depression,[18] hypertension, respiratory symptoms and illness,[19] immune responses, chronic multi-symptom illness, CHD and CVD, and modifiable health behaviors such as smoking, alcohol use,[20] sleep,[21] and physical activity that may be associated with deployment in support of the current wars.

In 2020 invitations were sent to an additional 500,000 service members,[24] including active duty, Reserve, and National Guard personnel.