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The widespread availability and use of potent combination anti-HIV treatment (ART) has allowed many HIV-positive people to have a near-normal life expectancy. ART provides this benefit by gradually reducing the amount of HIV in the blood to very low levels (commonly called undetectable). This sustained decrease in HIV allows the immune system to partially repair itself.
Although ART has many benefits, it cannot correct all of the immunological injury caused by HIV. For instance, untreated HIV infection causes a high level of inflammation in the body. Taking ART exactly as directed to help achieve an undetectable viral load greatly helps to reduce the level of inflammation, but this inflammation does not fall to the very low levels seen in healthy HIV-negative people. Some scientists suspect that the elevated level of inflammation seen even in ART users has the potential, over the long-term, to slowly degrade organ systems. There are clinical trials underway as scientists seek to find a way to safely reduce the residual inflammation found in ART users.
In the past decade, researchers in Canada and the United States have been studying the issue of food insecurity, which they define as follows:
Past research with HIV-negative people suggests that food insecurity is associated with heightened levels of inflammation. Now, in a recent study, scientists at 10 major clinics across the U.S. have found that food insecurity was linked to an increased risk of elevated inflammation among HIV-positive women. The link between food insecurity and inflammation was present even in women whose viral loads were suppressed due to good adherence to ART. This latter finding is important because previous studies had found that food insecurity was linked to poor adherence to ART and detectable viral loads.
The researchers called for programs that “address food insecurity” among HIV-positive women.
A team of scientists assessed information from an ongoing study called the Women’s Interagency HIV Study (WIHS, pronounced “wise”). WIHS, which has been underway for 25 years, collects extensive health and behavioural and other information from women at high risk for HIV as well as HIV-positive women. Recently WIHS started collecting information on food security from a subset of participants. The present analysis from WIHS focused on data collected from 421 HIV-positive women at one point in 2015. The average profile of these women upon entering the sub-study was as follows:
Scientists assessed levels of the following chemical signals in blood samples from participants:
Previous studies have found that levels of these chemical signals, among others, are elevated in HIV infection.
Study nurses did not recruit women with the following conditions:
All of the above-listed conditions have been associated with elevated inflammation in previous studies.
Overall, once scientists adjusted their findings for factors that could have affected inflammation (such as smoking, having a detectable viral load, high BMI and so on), they found that women who experienced food insecurity were more likely to have elevated levels of inflammation. On average, they had a 23% increased level of IL-6 and a 13% increased level of TNFR1, compared to levels in women who had not experienced food insecurity.
This heightened level of inflammation linked to food insecurity was not affected by viral load or CD4+ count.
Researchers suspect that food insecurity causes stress, and this stress in turn raises inflammation in HIV-positive women. However, this possible role for stress needs further study.
The present study was based on data collected at one point in time. Such studies are cross-sectional in their design and are a good first step in exploring an issue. However, studies of a more robust statistical design will be needed to better understand the connection between food insecurity and elevated inflammation. Such studies will be expensive.
Future studies could explore the following issues:
Resources
Canadian study links food insecurity to detectable viral loads and decreased CD4+ cells – CATIE News
Canadian study examines why some women fall out of the HIV care cascade – CATIE News
Comparing substance use patterns among women in Canada – CATIE News
Some Canadians spending less on food, heating because of prescription drug costs – CATIE News
Exploring HIV and inflammation – TreatmentUpdate 223
—Sean R. Hosein
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