Significant attrition at each stage of HIV care cascade in South Africa

Over half of HIV-infected men undiagnosed

There is significant attrition at each stage of the HIV care continuum in South Africa, according to a study published in the online edition of the Journal of Acquired Immune Deficiency Syndromes. The population-based research was conducted in North West Province and revealed that of those with HIV, only 48% of men and 76% of women were aware they were infected. Patients were then lost at each stage in the cascade of HIV care. Overall, just 22% of HIV-positive men and 56% of HIV-positive women had viral suppression, liberally defined as a viral load below 5000 copies/ml.

“These results provide a comprehensive picture of engagement with HIV care from diagnosis to viral suppression in a geographic area with little previous research but extremely high burden of disease,” write the investigators. “Based on the full HIV-positive population, it is quite clear that the greatest gap in engagement occurs at HIV diagnosis, indicating a critical need for improving case detection, particularly among men.”

South Africa has the largest antiretroviral therapy (ART) delivery programme in the world. Yet despite a massive scale-up in the delivery of ART, approximately 200,000 South Africans still die of AIDS each year and only half of those eligible for antiretroviral treatment are receiving appropriate treatment.

Glossary

continuum of care

A model that outlines the steps of medical care that people living with HIV go through from initial diagnosis to achieving viral suppression, and shows the proportion of individuals living with HIV who are engaged at each stage. 

virological suppression

Halting of the function or replication of a virus. In HIV, optimal viral suppression is measured as the reduction of viral load (HIV RNA) to undetectable levels and is the goal of antiretroviral therapy.

bias

When the estimate from a study differs systematically from the true state of affairs because of a feature of the design or conduct of the study.

linkage to care

Refers to an individual’s entry into specialist HIV care after being diagnosed with HIV. 

There are currently very limited data on engagement of patients in South Africa with the HIV care continuum. Population-based evidence is especially scarce.

A team of investigators therefore conducted a population-based study involving adults aged between 18 and 49 years in a rural districts of North West Province. The area is known to have a high HIV prevalence (in excess of 20%).

Data were gathered between January and March 2014 in Lewka-Teemane and Greater Taung sub-districts.

A total of 1044 individuals were included in the household-based survey and provided blood samples for rapid HIV testing, point-of-care CD4 cell monitoring and dried blood spots for viral load assessment. Participants were asked if they had ever tested for HIV, if they knew if they were HIV positive, and if so, whether they had ever been linked to care, if they were retained in care, if they were taking ART and if they were adherent to ART.

The investigators defined the HIV care continuum as follows:

  • Undiagnosed or newly diagnosed – HIV-positive patients with no reported previous test or a prior negative test.
  • Linked to care – reported ever seeing a doctor/nurse for HIV care.
  • Ideal linkage to care – saw a healthcare provider and had a CD4 count within three months of diagnosis.
  • Retained in care – if eligible for ART, reported being on therapy and seeing a healthcare provider every three months in the past year; if not ART eligible, reported seeing a care provider and receiving a CD4 count in the past year.
  • Adherent to ART – reported taking 90% or more of prescribed doses and no treatment interruptions.
  • Viral suppression – viral load below 5000 copies/ml.

Overall, 20% of men and 27% of women were HIV positive. Over half (52%) of men and a quarter of men diagnosed with HIV were previously unaware of their infection status.

Of those with HIV, only 44% of men and 75% of women reported ever linking to HIV care, and 40% of women and 29% of men had been linked to care and received a CD4 cell count within three months of diagnosis. Just one-third of men and 58% of women were retained in care, the majority of whom had started ART.

Although 33% of ART-treated men and 53% of women taking HIV therapy reported being fully adherent to their treatment, just 22% of men and 50% of women had a viral load below 5000 copies/ml.

Then investigators focused on engagement with the care continuum among patients who already knew they were HIV positive.

The majority (99% of women and 91% of men) was ever linked to care, but only 60% connected with care within three months of their diagnosis. Of those linked to care, 75% of men and 78% of women were retained in care. The majority of ART-treated patients (97% of men and 92% of women) reported being adherent to their therapy, but only 29% of men and 60% of women had a viral load below 5000 copies/ml. Only 26% had viral suppression when a threshold of 1000 copies/ml was used.

“Our findings demonstrate high reported adherence, but low rates of viral suppression, indicating a potential bias in self-reporting adherence data, which could be due to social desirability bias or over-reporting of medication adherence, as well as medication failure,” suggest the researchers.

They conclude that their data “provide a comprehensive picture of the HIV care continuum in the North West province and should be utilized to inform targeted programming.” Although noting that attrition occurs at every stage of the care continuum, the investigators suggest the most urgent need “is for improved HIV detection, particularly among men.”

References

Lippman SA et al. Attrition and opportunities along the HIV care continuum: findings from a population-based sample, North West Province, South Africa. J Acquir Immune Defic Synr, online edition. DOI: 10.1097/QAI.000000000001026 (2016).