Veterans Aging Cohort Study (VACS)
Cohort Description and Enrollment
Funded by the National Institute of Medicine (NIH), primarily the National Institute of Alcohol Abuse and Alcoholism (NIAAA) and the National Heart, Lung, and Blood Institute, (NHLBI), VACS consists of two ongoing cohorts. The first, assembled from national VA data alone and beginning in 1997, is a cohort of >40,000 HIV- positive veterans and a one to two (>80,000) age/race/site matched sample of uninfected controls, used to understand the overall impact of HIV, HIV treatment, and comorbid conditions on morbidity and mortality. At the end of each fiscal year, this cohort is updated to include veterans with new diagnoses of HIV infection and matched controls receiving care in the same fiscal year.
VACS is complemented by a prospectively-consented, substudy cohort of veterans with and without HIV infection, currently in care at nine VA medical centers around the country (VACS 9). This in-depth cohort allows us to “get behind” gross associations with outcome, to better understand the likely complex and overlapping etiologies resulting in differences outcome and patient utilization. As in the main cohort, enrollment is ongoing. As new veterans present for care with HIV infection they will be offered enrollment, and an age/race/site matched control will be offered enrollment from the general-medicine clinic.
Since 2002, VACS 9 has consented and enrolled >7,000 patients (half HIV-positive, half HIV-negative controls) in Atlanta, Baltimore, the Bronx, Dallas, Houston, Los Angeles, Manhattan/Brooklyn, Pittsburgh, and Washington, D.C. In addition to having access to complete medical-record information (including pharmacy fills, laboratory data, pathology data, radiology data, and progress notes) and administrative data (including utilization and diagnostic codes), VACS 9 draws from several additional sources of data: (1) patient and provider surveys (quality of life, symptoms, adherence, alcohol use, drug use, health habits) at the time of the visit; (2) telephone interviews providing in-depth data on alcohol use and medication adherence; (3) banked serum, plasma, and blood pellets for future hypothesis testing; (4) The National VA Cancer Registry; (5)The QUERI Myocardial Infarction Registry; (6) The National Death Index Cause of Death File;and (7) Medicaid and Medicare Files for outside utilization.
In depth descriptions of both samples have been published (references below) and can also be found on our website. VACS welcomes proposals for analyses and sub-studies (proposal form).
Predominantly male, with a majority of the HIV infected sample reporting heterosexual exposure (88%) and a large minority reporting at least some homosexual exposure (48%). Past IV drug use is relatively common (19%) and 45% of HIV infected are co-infected with hepatitis C. Controls are matched for age, race, and year of active use of VA healthcare.