Interaction of the Aging Process with Neurobehavioral and Neuro-AIDS Conditions in the HAART Era

The foregoing introduction to the epidemiology of aging in HIV-1 infection leads us to an important preliminary conclusion. That is, the study of older age in HIV-1 infection is more properly considered as (i) the study of a population of newly infected older individuals and (ii) the study of a separate group of long-term HIV-1-infected patients successfully treated with highly active antiretroviral (ARV) therapy (HAART). The authors used a generalized linear models approach with age category, HIV-1 disease category (HIV-1 seronegative, CDC stage B/early symptomatic HIV-1 infection, and CDC stage C/AIDS), and their interaction as predictors of the total number of MCMD symptoms (zero to six) defined by the American Academy of Neurology. Given the hypercortisolemia-induced neuronal cellular toxicity associated with major depressive disorder and with chronic stressor exposure, both of these conditions may enhance the likelihood of neurocognitive impairment (NCI) and neurocognitive disorder when superimposed upon the toxicities associated with the aging process and HIV-1 infection of the brain. In addition to the consideration of how aging might interact with HIV-1 infection in specific neuro-AIDS conditions, an overarching issue exists. That issue is related to how an increased frequency of medical comorbidities might interact with aging in the likelihood of expression of neuro-AIDS conditions.