In this study, we set out to investigate the predictors of viral load suppression among ALHIV receiving ART in the Ehlanzeni district of South Africa. The proportion of ALHIV with viral suppression after six months of ART initiation was relatively high at 74.31% compared to another study conducted in South Africa , but falls short of the global target of 95%. Furthermore, our study revealed that being female, and having most recent CD4 count level > 200 were associated with viral suppression. On the other hand, being on ART for more than six months, as well as being on second line treatment are enhancing factors for viral non-suppression.
Evidence on the relationship between gender and viral load suppression is mixed. While one study showed that males were more likely to achieve viral load suppression compared to females , another study found that males are more likely to achieve viral non suppression . However, we found that females were more likely to attain viral suppression compared to males. Adherence among males ALHIV is poor compared to females; males have poor treatment seeking behaviours  and as such to get males to test for HIV, link and retain them to ART care remains a challenge . The poor treatment outcome reported among males have been attributed to strong gender norms and practices specifically the perception of masculinity inherent within societies in South Africa. In addition, lack of male-friendly services inhibits males from seeking health care services [26,27,28].
The literature indicates that older age group or adults can achieve viral suppression because they are able to successfully take their ART medication regularly without supervision i.e. possess self-efficacy and self-competency on ART adherence . Interestingly, our study did not show any significant difference between viral suppression among adolescents in the age group 10–14 years and 15–19 years. This is likely because if no support is provided, adolescents (10–19 years) are faced with psychosocial challenges, lack self-efficacy and self-esteem, and are unable to self-manage themselves with regard to medication adherence . However, a retrospective study conducted among adolescents registered in the Cape Metropole ART clinic in South Africa found younger adolescents (10–14 years) were more likely to achieve viral suppression compared to older adolescents (15–19 years). It was reported that the older adolescents face adherence challenges as a result of transitioning from adolescence to adulthood in which they are expected to self-manage themselves with regard to medication adherence .
We also found that longer duration (18 to 24 months) on ART was a risk factor for viral non-suppression. This is contrary with evidence that patients on ART for shorter period are more likely to experience virological failure . Our study findings is interesting given that patients who have been on treatment longer have more experience in managing their treatment . Similar findings were reported in a study, which reported that adolescents who had been on ART between 6 and 12 months were more likely to have viral non-suppression (viral load > 400 RNA copies/mL) compared with those who had been on treatment for longer .
Immunological treatment failure refers to a CD4 cell count of < 100 cells/µL after 6 months of therapy . According to the WHO guidelines, a decreasing CD4 cell count is considered a proxy marker for treatment failure when viral load monitoring is not available, and should trigger a switch in ART, particularly if the CD4 cell count is < 200 cells/µL . Although the relationship between viral non-suppression and immunological responses, is not always consistent , our study found that adolescents with CD4 cell count > 200 cells/µL at last ART visit were more likely to achieve virological suppression. However, the ability of CD4 counts to predict virologic failure is poor .
Studies have shown that delayed detection of treatment failure may increase drug toxicity, which in turn lead to the accumulation of drug resistance-associated mutations, hence may result in increased morbidity and mortality . On the contrary, a timely switching to second-line ART after virological failure along with enhanced adherence counselling is a protective factor against viral progression and mortality . However, we included ALHIV who were already initiated on second line ART to determine whether second-line ART would be a successful ‘rescue’ for viral suppression. Our findings showed that adolescents on second-line treatment were less likely to attain viral suppression. It is possible that those on second line regimen could have a history of poor adherence behaviour that continues in spite of being on the ‘rescue’ regimen. There is also evidence that having a history of treatment failure is a risk factor for viral suppression . Furthermore, second-line regimens are more complex than first-line regimens, are often twice daily regimens and have more adverse side effect than first-line regimens hence impacting negatively on adherence. Unfortunately, assessing HIV resistance among HIV naïve patients is challenged by cost and volume of HIV positive patients in South Africa.
Several implications arise from our findings. First, to achieve the 95% global target by 2030, there is a need to design an intervention (i.e. psychosocial support) aimed at ALHIV to improve self-efficacy and self-competency so that they are able to adhere to their ART medication. Adopting a combination of multiple approaches including psychosocial support intervention may be necessary to improve adherence. For instance, providing social support and focusing on psychosocial needs of adolescents to bolster their self-esteem and self-efficacy will in turn improve their self-management regarding medication adherence and subsequently improve their treatment outcomes.
Timely and accurate identification of virological failure is crucial to avoid misclassification of non-suppression leading to switching to a second-line or third-line which are costly and can lead to viral non suppression. It is recommended that second line regimens especially for ALHIV are simplified and changed to once daily, and less toxic regimens which could improve adherence and in turn lead to viral load suppression. Furthermore, providing enhanced adherence counselling for ALHIV who are males, on second line regimen and being on ART for more than 18 months is very crucial.
This study has a number of limitations, which should be taken into account when interpreting the findings. First, adolescents who are eligible for viral load assessment but failed to have it done because they were lost to follow-up, died or transferred out, were not included, which could have resulted in overestimating the rate of viral load suppression. Second, as is the case for all cross-sectional studies, it is subject to other risk or confounding factors that may be present but were not measured. For example, household income status, head of household, type of social support and psychosocial well-being. Third, as is the case for routine programme data which is exposed to data quality issues. We were not able to delineate which clients had low CD4 because they were early in treatment and been allowed to have a drop in CD4 before initiation, and those that had been doing well and now had a drop in CD4. Similarly, the type of ART regimen used for first- and second-line treatment were excluded from analysis due to poor data capturing. Finally, the Tier.Net medical electronic record only captures the last viral load test done, as a result, we were unable to measure two consecutive viral load test three months apart for those with VL > 50 RNA copies/mL making it challenging to explain what is going on for those who are not undetectable as recommended by World Health Organisation.