Smoking largest contributing factor to non-AIDS related cancers
Smoking is the biggest contributing factor to the total burden of non-AIDS related cancers for people living with HIV (PLHIV) in the United States, when compared to all other risk factors. Studies show that PLHIV who smoke, or used to smoke, have a 37 percent increased risk of non-AIDS related cancers in comparison to a control group, and a 29 percent increased risk when lung cancer is not taken into the equation. Halting the progression of HIV to AIDS could prevent another up to eight percent of non-AIDS cancer. This show different research studies presented at the Conference on Retroviruses and Opportunistic Infections (CROI) last week.
A large cohort study looked at the incidence of non-AIDS-related cancer and found that lung cancer was the most common non-AIDS-related cancer in this cohort. The study concluded that smoking had a much greater impact compared with the other risk factors that were considered, including a low CD4 cell count, which had the second greatest impact.
Since the introduction of antiretroviral therapy (ART), there has been a significant decrease in AIDS-related cancer incidence and a significant increase in non-AIDS related cancer incidence among PLHIV. A number of factors are believed to contribute to this increased trend, although none of these factors have been confirmed to be contributing most significantly. The increased age of the population of PLHIV was believed to contribute strongly towards the increased incidence of non-AIDS related cancer, as it also does in the general population, thus simply reflecting the normal ageing process. A higher frequency of smoking, recreational drug or alcohol use, and higher rates of co-infection with other viruses, specifically cancers relating to hepatitis B (HBV) and hepatitis C (HCV), is also considered to contribute to the increased incidence of non-AIDS related cancer in PLHIV.
This new research indicates that smoking is the main risk factor contributing to the development of non-AIDS related cancer. In order to reduce the non-AIDS cancer burden in adults living with HIV, effective interventions to reduce smoking are needed, along with a continued focus on HIV treatment. This effectively means that HIV prevention programmes should start targeting individuals at risk for HIV and include measures to prevent smoking.