The Multicenter AIDS Cohort Study (MACS)
is an ongoing prospective study of the natural and treated histories of HIV-1 infection in
homosexual and bisexual men. The MACS has been conducted since 1984 at sites in Baltimore, Chicago,
Pittsburgh and Los Angeles. Over the past 30 years, the aims of the MACS have evolved from the clinical
characterization of AIDS in men who have sex with men (MSM) to the elucidation of the natural history and
then the treated history of HIV infection. Data from the MACS have been the basis of more than 1300 publications in peer-reviewed journals. In 1987, the Center for the Analysis and Management of the MACS Data (CAMACS) was established at
the Johns Hopkins School of Public Health.
Data and specimens collected at semiannual study visits include: detailed questions covering sexual practices, HIV-related symptoms, and utilization of health services, demographic and psychosocial characteristics, a quality of life survey, a physical examination, a detailed form on medications used as prophylaxis and/or treatment, a neuropsychological screening and examination, blood samples to measure hematologic variables including enumeration of T-cell subsets and HIV viral load, and the allocation of samples to be sent to the National Repository. These specimens are invaluable for helping to understand the pathogenesis of HIV-1 infection.
The breadth and impact of our scientific accomplishments (see Contributions) have guided public health policy and the care and treatment of people with HIV/AIDS. As a consortium of four clinical research sites and a data coordinating center, the MACS recruits and retains participants, collects and stores clinical specimens, and conceptualizes, designs, and implements a multidisciplinary, interdependent scientific agenda and research plan. Our ability to respond rapidly to a changing epidemic, whether it be the advent of effective combination antiretroviral therapy (cART) or a shifting demographic, ensures that we will succeed in addressing the key questions facing HIV research today, including the effects of HIV, cART, and age on HIV-induced inflammation and immune dysfunction and on non-AIDS-defining outcomes including cancer, cardiovascular, liver, metabolic, neurologic, psychologic, and renal disease.