Structural barriers to antiretroviral treatment: a study using population-based CD4 cell count and linked antiretroviral treatment programme data

Abstract

BackgroundThe promise of an AIDS-free generation rests on treatment as prevention to reduce HIV incidence. Treatment as prevention depends critically on high antiretroviral treatment (ART) coverage. However, even under current national ART guidelines coverage remains far from universal in sub-Saharan Africa. We examined structural barriers to ART access in a community in rural South Africa, which has a very high adult HIV prevalence (28%) and incidence (approximately three new infections per 100 person-years). MethodsWe did a population-based survey of CD4 cell count among 5000 randomly selected participants in the 2010 round of a longitudinal, population-based HIV surveillance study. The study was carried out by the Africa Centre for Health and Population Studies in the Hlabisa subdistrict of KwaZula-Natal. We identified the people needing ART among the HIV-infected surveillance participants as those who were either enrolled in the local ART programme (ie, people needing and receiving ART) or people who were not enrolled in the programme but had a CD4 cell count below a certain threshold (ie, people needing ART but not yet receiving it). We applied two different CD4 cell count thresholds (≤200 and ≤350 cells per μL), leading to two different samples of people needing ART (n=376 and n=610). We then used logistic regression to explore the effect of socioeconomic factors (sex, age, education, wealth, distance to the nearest ART clinic, urban/rural residence, and migration status) on the binary outcome of ART enrolment in relation to ART need. FindingsART coverage was 72% in the 376 individuals who were either on ART or had a CD4 count of 200 cells per μL or fewer, and 45% in the 610 individuals who were either on ART or had a CD4 count of 350 cells per μL or fewer. Women who needed ART were significantly more likely to receive treatment than were men who needed it (48% vs 34%; p=0·003 for the ≤350 cells per μL threshold). The age pattern of ART coverage increased from approximately 20% at age 20 years to 60% at age 45 years, declining to 40% at age 70 years for the 350 cells per μL or fewer threshold. Controlling for other factors, among those needing ART, women were more than twice as likely to be taking ART than were men (adjusted odds ratio 2·43, 95% CI 1·36–4·33; p=0·003) and every additional km distance from the nearest clinic decreased the likelihood of ART used by approximately 20% (adjusted odds ratio 0·79, 95% CI 0·67–0·94; p=0·007). Education, wealth, and migration did not affect ART access. When we separated women into those who had not been pregnant since inception of the ART programme in 2004, and those who had been pregnant, pregnancy was a significant determinant of ART access, but explained only a small fraction (<10%) of the difference in ART access between women and men. When we used the second sample of 610 individuals, the findings remained essentially the same. InterpretationWorking towards universal coverage goals, ART programmes need to improve access for men, young and old people, and remote populations. Interventions improving geographical accessibility of ART programmes, such as subsidised transport or the opening of more ART clinics in remote areas, are likely to help to overcome important structural barriers to access. FundingThe Africa Centre for Health and Population Studies demographic and HIV surveillance is funded by the Wellcome Trust. TB and FT received financial support from the Wellcome Trust and through 1R01-HD058482-01 from the National Institute of Child Health and Human Development, National Institutes of Health.