Social determinants of health —the social conditions in which people grow up, live and work— can influence the risk of contracting AIDS and the mortality associated with the disease. This is the main conclusion of a new study carried out by the Barcelona Institute for Global Health (ISGlobal), a centre supported by the "la Caixa" Foundation, and published in The Lancet Regional Health.
The research team evaluated a cohort of 28.3 million people, representative of the low-income Brazilian population, based on data collected between 2007 and 2015. This is the largest evaluation of social determinants of health and AIDS in Brazil to date. The researchers concluded that social determinants related to poverty and social vulnerability are strongly associated with a higher burden of AIDS. Specifically, individuals who are black, economically disadvantaged, and lack access to education, are disproportionately affected by the burden of the disease.
"The results of the study show that social determinants of health play an important role in the burden of HIV/AIDS in a highly unequal country like Brazil. The whole chain of events related to the disease, whether it is the risk of becoming infected, developing advanced disease or dying from it, is influenced by these factors," says Davide Rasella, ISGlobal researcher and lead author of the study.
Despite Brazil's pioneering response to the HIV/AIDS epidemic, being the first middle-income country to offer free antiretroviral treatment to all people living with the disease and widespread free HIV testing, the mortality rate from the disease in Brazil in 2020 was 6 per 100,000 inhabitants. Of the new infections registered in Latin America in 2020, almost half (48%) were recorded in Brazil.
The lower the wealth, the higher the AIDS incidence and mortality
According to the results of the study, lower wealth was strongly associated with higher AIDS incidence and mortality. Specifically, people with lower wealth were 55% more likely to become infected and 99% more likely to die. "Lower wealth may be closely related to social exclusion and food insecurity, which are potential barriers to early diagnosis and to starting or adhering to HIV/AIDS treatment," says Rasella.
Lower levels of education were also associated with higher AIDS incidence and mortality. Illiterate people were 46% more likely to become ill and 176% more likely to die than those with higher education. This can be explained by factors such as lack of access to health information, risky sexual behaviour and difficulty in accessing health care. Previous studies have shown that people with lower levels of education are more likely to engage in risky sexual behaviour, to be diagnosed with HIV/AIDS late, and to have poorer access to and adherence to treatment.
In addition, black people had a 53% higher risk of AIDS and a 69% higher risk of death than those who identified as white or Asian. This increased risk could be a consequence of structural racism, including racial health inequalities in access to and quality of health services. "Structural racism in Brazil, as in many other parts of the world, also manifests itself in poorer living conditions, which expose people to worse HIV/AIDS outcomes," notes Rasella.
The effects of cash transfer programmes
Of the total participants in the evaluated cohort, 64.75% were beneficiaries of the Bolsa Família cash transfer programme. Individuals who received the Bolsa Família cash transfer for less than two years had a higher risk of developing HIV/AIDS than those who did not meet the eligibility criteria for the programme. A protective effect was also observed for long-term receipt, with those who received the benefit between 5 and 10 years or for more than 10 years having a lower risk of becoming ill and dying from the disease.
"This may be due to the poverty-reducing effect of the programme's subsidies and the requirements for receiving these benefits, such as visiting health services and attending school for children and adolescents. This brings families closer to the services that provide diagnosis and health education," argues Rasella.
Implications for prevention programmes
The results of the study highlight the need to invest in public health policies to expand access and ensure equity in health care, prioritising people with greater social vulnerability. "Our study has important implications for HIV/AIDS prevention and control programmes in other low- and middle-income countries. The results provide further evidence of the need to reduce social inequalities by focusing on key health determinants that affect HIV/AIDS," says the ISGlobal researcher.
"Without the implementation of meaningful interventions to reduce inequalities, there is a risk that the current increase in poverty rates and social vulnerability will reverse the progress made in the fight against HIV/AIDS in recent decades and hinder the achievement of the Sustainable Development Goals related to this disease," concludes Rasella.
Lua I, F. Silva A, S. Guimarães N, et al., Rasella D. The effects of social determinants of health on acquired immune deficiency syndrome in a low-income population of Brazil: a retrospective cohort study of 28.3 million individuals. The Lancet Regional Health. Volume 24, 100554, August 2023. 10.1016/j.lana.2023.100554