Strengthening understanding of effective adherence strategies for first-line and second-line antiretroviral therapy (ART) in selected rural and urban communities in South Africa: Adherence to antiretroviral treatment in selected rural and urban communities in South Africa

Abstract

Although there is much research on adherence to ART, there remains a dearth of studies relating to the multi-level factors associated with adherence to treatment. In addition, there is a lack of knowledge about the effectiveness and impact of strategies currently employed to promote adherence in people living with HIV (PLHIV) who are taking ART. In this thesis, a multilevel socio-ecological framework was used to provide information about risk factors affecting treatment adherence at different levels and also guided a systematic review of research assessing the impact or effects of intervention strategies in improving treatment adherence. Findings from chapter 3 showed that younger patients, male patients, patients with low CD4 cell counts, and patients who were initiated on ART between 2004 and 2010 all had poorer clinical, treatment and retention outcomes, particularly those on second-line ART Chapter 4 reported that just under three-quarters (72%, n=597/825) of the patients remained in care over the reported period. Being <25 years of age, male sex, and geographical transfer (started initial treatment in a different region) independently predicted low CD4+ cell counts and virological failure on second-line treatment. In chapter 5, we found that being male was an independent risk factor for self-reported difficulties with adherence, suboptimal adherence measured through pill count, and virological failure. PLHIV who experienced moderate or severe depressive symptoms or had low household income were at increased risk of poor adherence and/or virological failure and may benefit from additional ART adherence support. In Chapter 6, we found that single and unmarried people living with their partners were more likely to experience virological failure compared to those who were married. The more toxic second-line multi-pill, which is taken multiple times a day, was seen as significantly harder to take than a single tablet daily, well-tolerated first-line regimen. Participants experiencing medication-related difficulties in taking second-line ART and experiencing side effects were also subjective predictors of virological failure. We also found that participants with virological failure were more likely to have treatment-related side effects. Of the total 77 studies reviewed in chapter 7, 60% (n=46/77) reported improved adherence based on the described study outcomes while 21% (n=16/77) reported no significant difference between studied groups. The interventions described in this review ranged from adherence counselling to more complex interventions such as mobile health (mhealth) interventions. Combining multi-level models, the evidence from the studies presented in this thesis enabled us to identify the barriers to and facilitators of adherence for PLHIV on ART and recommend intervention strategies to improve treatment adherence. Our research found that many factors influence the ability to engage individuals in HIV care successfully. These factors include being male, being younger, experiencing ART-related side effects, having a low household income, presence of food insecurity, and experiencing moderate or severe depressive symptoms. Our study also provided evidence that community-and home-based, digital, or mhealth and adherence counselling interventions can improve adherence to treatment for chronic conditions. Our findings also emphasized the need to develop a gold standard (or uniform measures) for measuring adherence.