Bear in Mind
The design of this study was cross sectional; this is analogous to a snapshot in time. It can only provide a glimpse of the state of health of participants.
There was no control or comparison group in the Italian study. Findings from a cross-sectional study are not definitive.
A more useful study would have been to recruit a larger number of participants, both HIV positive and HIV negative, to monitor and test them repeatedly
over several years. This would be a study of a different design called a longitudinal study. However, longitudinal studies are expensive and sometimes difficult to recruit for and maintain. Cross-sectional studies can, however, provide limited findings that
can be used to make the case for funding a longitudinal study.
Perhaps the most important finding from the Italian study is that cardiovascular disease risk can affect the workings of the brain, particularly the
parts involved in memory and thinking in HIV-positive people. A similar effect has been observed in HIV-negative people. As ART enables HIV-positive people to live near-normal life spans, the focus of care may need to shift to monitoring for and treating the
diseases of aging.
Other studies have also found an increased risk for CVD among HIV-positive people. In part, this may be a consequence of HIV infection and the persistent
inflammation that this virus triggers. In experiments with monkeys infected with simian immunodeficiency virus (SIV, which can cause an AIDS-like disease in susceptible monkeys), researchers have found signs of premature cardiovascular disease. And another
study by a team experienced in HIV brain research used MRIs and found a connection between problems controlling blood sugar and damage to structures deep within the brain.
All of this research underscores the need for longitudinal studies to assess the risk of CVD in HIV-positive people. It also highlights the necessity
of potential interventions for people at risk for CVD with combinations of therapy (exercise, medicine, changes to the diet, help for smoking cessation, stress reduction and so on) so that health can be maintained or improved. Moreover, by preventing and treating
co-morbidities, the research team suggests that, in theory, doctors may be able to reverse the mild neurocognitive impairment that seems to be relatively common in studies with HIV-positive people in the present era.
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