Vietnam Era Twin Study of Aging (VETSA), United States, 2002-2019

The Vietnam Era Twin Study of Aging (VETSA) projects began in 2002 with the goal of understanding risk and protective factors, including genetics, for cognitive and brain aging starting in midlife. This NIH funded longitudinal study has completed three waves of data collection (2002-2008; 2008-2014, 2015-2020) following the same group of non-patient, community dwelling male veteran twins from when they were average age 56 to average age 68. A fourth wave of data collection began in October 2021. Although the men are American veterans, this is not a VA sample. This is a nation-wide sample with participants flown into sister data collection sites at either University of California San Diego or Boston University. The VETSA study encompasses multiple linked grants and data collections with two studies funded continuously since 2002--The VETSA Longitudinal Twin Study of Cognition and Aging and The VETSA Longitudinal MRI Twin Study of Aging. Because of the broad interests of the investigators, while study data focus most heavily on in-person cognitive testing, a wide array of psychosocial, demographic, medical history, physical functioning, and personality measures were also collected. While some measures were only collected at baseline, the majority are repeated at every data collection. At each wave of data collection, participants completed a lengthy psychosocial questionnaire at home then came to the testing site for a full day (~8 hrs) of in-person testing. Participants were housed for either 2 nights if only part of VETSA aging or 3 nights if they qualified for the MRI data collection.