In this study, we set out to investigate the predictors of viral load suppression among HIV-positive adolescents (10–19 years) receiving antiretroviral therapy (ART) in the Ehlanzeni district of South Africa before the introduction of the RTC adolescent program. The proportion of adolescents living with HIV with viral suppression was relatively high at 73.96%, but falls short of the global target of 90%. Furthermore, our study revealed that being female, on ART for more than 6 months, having CD4 count level >200 at baseline and last ART visit were protective factors against viral non suppression. On the other hand, being on second line treatment was an enhancing factor 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 [20], another study found that males are more likely to achieve viral non suppression [24]. However, we found that females were more likely to attain viral suppression compared to males. Adherence among males living with HIV is poor compared to females; males have poor treatment seeking behaviours [25], and as such to get males to test for HIV, link and retain them to ART care is quite a challenge [26]. 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 addition, lack of male friendly services inhibits males from seeking health care services [26–28].
The literature indicates that older age group or adults can achieve viral suppression because they possess self-efficacy and self-competency on ART adherence [9]. 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 [29]. 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 [20].
We also found that shorter duration on ART was a risk factor for viral non-suppression. This is consistent with evidence that patients on ART for shorter period are more likely to experience virological failure [9]. The contrary is to be expected given that patients who have been on treatment longer have more experience in managing their treatment [9]. 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 [9].
Immunological treatment failure refers to a CD4 cell count of <100 cells/µL after 6 months of therapy [9]. 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 [9]. Although the relationship between viral non-suppression and immunological responses, is not always consistent [9], our study found that adolescents with CD4 cell count >200 cells/µL at baseline and at last ART visit were more likely to achieve virological suppression. However, the ability of CD4 counts to predict virologic failure is poor [11]. The use of CD4 count may, therefore, lead to unnecessary switching to second-line ART among patients with suppressed viral replication, or cause undue delays in switching among patients with real – but undetected – virological failure.
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 [30]. On the contrary, switching to second-line ART on a timely manner after virological failure along with adherence counselling is a protective factor against viral progression and mortality [10]. Our findings showed that adolescents on second line treatment were less likely to attain viral suppression. This is because 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. Furthermore, the misclassification of treatment failure could lead to the premature switch to and use of valuable second-line regimens, which are costly and may represent the last available regimen [30]. Our findings is consistent with another study that found among ART adherent patients, having a history of treatment failure is a risk factor for viral suppression [17].
Findings implications
Several implications arise from our findings. First, psychosocial support interventions designed to improve adherence should target adolescent (10-19 years) living with HIV. 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 adolescents are simplified and changed to once daily, and less toxic regimens.
Study limitations
This study has a number of limitations, which should be taken into account when interpreting the findings. Firstly, 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. Secondly, as is the case for all retrospective cohort 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.