Nearly two million people in sub-Saharan Africa may have advanced HIV disease

Men in sub-Saharan Africa are much more likely to have advanced HIV disease –including large numbers who have a low CD4 count despite taking treatment and being virally suppressed. It remains crucial to monitor CD4 count, according to a World Health Organization (WHO) study of 12 countries presented to the Conference on Retroviruses and Opportunistic Infections (CROI 2024) by Dr Dominik Stelzle in Denver earlier this month.

Background

While people with advanced HIV disease have more opportunistic infections, increased chances of hospitalisation and death, there are scarce estimates of how many people are impacted by it in sub-Saharan Africa.

A person with HIV is considered to have advanced HIV disease if their CD4 count falls below 200 cells, or they show symptoms of HIV clinical stages 3 or 4, according to the WHO classification system. These late stages are usually characterised by illnesses such as pneumocystis pneumonia, cryptococcal meningitis and Kaposi’s sarcoma.

As the HIV epidemic has matured, the focus has moved away from death due to HIV-related complications to ensuring viral suppression and preventing onward transmission. As a result, advanced HIV disease – and its accompanying opportunistic infections – have become neglected.

“Although treatment coverage has increased substantially in recent years, any associated reductions in AIDS-related deaths have been smaller and slower than expected,” Dr Nathan Ford and colleagues argued in The New England Journal of Medicine earlier this year. “The proportion of people with advanced HIV disease remains high: it is estimated that more than 4 million people have advanced HIV disease, and each year more than 600,000 of them are expected to die.”

“Many of these deaths can be prevented — if the global HIV/AIDS community reconsiders who is at risk for the worst outcomes; determines what infections lead to the greatest morbidity and mortality; invests in new tools for diagnosing, preventing, and treating these conditions; and supports the systems required for delivering those tools effectively.”

The study

WHO researchers used Population-based HIV Impact Assessment (PHIA) survey data from 12 sub-Saharan African countries, which includes blood samples tested for HIV antibodies, HIV viral load and CD4 count. These surveys are nationally representative and include people aged 15 and older present in the household when the survey is carried out. This means that these numbers may underestimate the numbers of people with advanced HIV disease, as they do not account for those who are hospitalised at the time of the survey.

Countries included were Cameroon, Côte d’Ivoire, Eswatini, Ethiopia, Lesotho, Malawi, Mozambique, Namibia, Tanzania, Uganda, Zambia, and Zimbabwe. In most instances, data were available from 2016 or 2017, but four countries had more recent survey data from 2020 and 2021.

A total of 24,621 people living with HIV were surveyed: most of these were women (65%) and lived in rural areas (55%). In terms of the HIV cascade, just over a quarter were not aware of their HIV status (26%), while 4% were aware but not on antiretroviral therapy (ART), 8% were on ART but not virally suppressed and the majority (62%) were virally suppressed (below 1000 copies/ml).

Men are much more likely to have advanced HIV disease

Among the samples, 2172 people had a CD4 count less than 200, a weighted prevalence of 10% (95% Confidence Interval: 9.5% to 10.6%) presenting with advanced HIV disease. The median CD4 count was 483; 19% of people had CD4 counts between 200 to 349, 24% had CD4 counts between 350 to 499 and 47% had counts over 500 cells.

Countries that had a smaller proportion of people with advanced HIV disease included Côte d’Ivoire, Lesotho, and Malawi, while Tanzania and Ethiopia had the highest number of people presenting with advanced HIV disease.

While urban vs rural residence and wealth level did not seem to impact the numbers of people with advanced HIV disease, there was an association with age: younger people between 15 and 29 were less likely to have advanced HIV disease compared to those between the ages of 30 to 49. However, the largest difference was seen for gender: men were much more likely to have advanced HIV disease (13%) than women (8%), despite fewer men having HIV overall.

By HIV treatment category, people who were on ART but not virally suppressed were most likely to have advanced HIV disease (30%), followed by those who were aware of their HIV status but not on ART (21%). The next highest group included people who were unaware of their HIV status (15%), while those on ART and virally suppressed comprised the smallest group with advanced HIV disease (5%), as expected.

When looking at the HIV treatment cascade separated by gender, the proportion of men on ART but not virally suppressed with advanced HIV disease was a staggering 36%, compared to only 26% of women. Similarly, there was a stark gender difference in terms of people on ART who were virally suppressed – while only 3% of women in this category had advanced HIV disease, nearly 8% of men did.

Using these data to estimate the total number of people with advanced HIV disease among 24.2 million people living with HIV in sub-Saharan Africa, 1.9 million would have advanced HIV disease, 44% of whom would be virally suppressed. Of these, there would be nearly equal numbers of men and women with advanced HIV disease, even though men comprise only 8.6 million of the total number of people living with HIV. Even more concerning in terms of this gender disparity: nearly half of all the men with advanced HIV are virally suppressed (49%).

Conclusion

“Men have a higher prevalence of advanced HIV disease and overall, around two-thirds of all people with advanced HIV disease are actually on treatment,” Stelzle concluded. “Nearly half of all people have a suppressed viral load – which means that simply putting people on treatment, having people retained in care, is not enough to diagnose advanced HIV disease and prevent opportunistic infections. Timely CD4 testing and linkage to care is crucial for advanced HIV disease diagnosis and treatment.”