SAN DIEGO - Naval Health Research Center’s (NHRC) Millennium Cohort Study, the largest prospective health study of U.S. service members and veterans, celebrates its 25th anniversary in July.
Launched in 2001 as a result of the 1999 National Defense Authorization Act (NDAA), Section 743, which mandated, "a longitudinal study to evaluate data on the health conditions of members of the armed forces upon their return from deployment." The largest and longest study in military history has documented the long-term physical and mental health of over a quarter of a million service members and veterans, providing robust, long-term data on the health effects of military service.
The study has guided evidence-based policy and clinical practice guidelines across the U.S. Military and the Department of Veterans Affairs (VA). The study’s longitudinal data, collected through recurring surveys and linked to comprehensive administrative records, has informed policy on the long-term health effects of deployment and service. Findings have informed current clinical practice guidelines in areas such as management of chronic multi-symptom illness and insomnia/obstructive sleep apnea and have contributed to guideline development for post-traumatic stress disorder and major depressive disorder.
“The Millennium Cohort Study is an irreplaceable resource for our nation’s military and veterans’ health systems,” said Rudy Rull, the study’s principal investigator. “Its 25-year legacy offers an in-depth look at the health journey of our service members and veterans, and there is more to discover about the long-term effects of their service.”
The study surveys over 260,000 participants every 3-5 years. Researchers are currently finalizing its seventh data collection cycle, while planning the next enrollment of new service member participants.
“The success of the Millenium Cohort Study rests on the commitment of its active duty, reserve and guard participants across all branches,” said Sheila Castañeda, the study’s deputy principal investigator. “The dedication of our participants has been vital to understanding the health challenges of military life, from the stresses of deployment and integrating back to civilian life.”
As the study enters its next quarter century, researchers are looking forward to focusing on emerging areas of operational importance, such as brain health and cognitive function, long-term physical health (such as cancer and cardiovascular disease) and environmental and occupational exposures.
"For over two decades, the Millennium Cohort Study has been our steadfast commitment to understanding the long-term health of our nation's armed forces and veterans,” said Rear Adm. Rick Freedman, Acting U.S. Navy Surgeon General. “This research is a testament to our promise to care for those who serve, providing invaluable insights to their health needs while honoring our commitment to the lifelong well-being of our service members and their families.”
The Millenium Cohort Study is expected to continue to enroll and follow up with participants through 2068. For more information, please visit: [millenniumcohort.org](https://www.millenniumcohort.org/).
NHRC, part of Navy Medicine Research & Development, supports Navy, Marine Corps and joint U.S. warfighter health readiness and lethality with research and development that delivers high-value, high-impact solutions to the health and readiness challenges the U.S. military population faces on the battlefield, at-sea, home and abroad.