Research in context
Evidence before this study
The 2013 WHO consolidated guidelines on the use of antiretroviral therapy for the treatment and prevention of HIV infection promoted the use of text messaging to improve adherence to therapy. Before we did our systematic literature search, we searched MEDLINE and Embase to find systematic reviews published up to June 1, 2016, that assessed the full spectrum of interventions to improve adherence, using the search string “(HIV or antiretroviral therapy) AND (adherence) AND (systematic review or meta-analysis)”. Previous systematic reviews have been restricted to pairs of interventions; the only network meta-analysis that explored adherence interventions for antiretroviral therapy was limited to studies in Africa. Low rates of adherence have been reported too in high-income settings, so there is a need to explore the evidence at the global setting.
Added value of this study
This was the first network meta-analysis to consider all adherence interventions within a single global analysis. We show that adherence interventions have small effects and that they are not easily statistically distinguishable from one another. These results support the benefits of text messaging, counselling, and supporters, and they further support the additive effect of behavioural and cognitive interventions. Novel to this study, time of outcome measurement with respect to the intervention (ie, whether adherence was assessed while the intervention was still active rather than previously completed) was an effect modifier, suggesting that the effects of interventions wane over time.
Implications to all available evidence
With the recent scale-up of antiretroviral therapy programmes and increasing number of people living with HIV, steps to improve and maintain consistent long-term adherence to antiretroviral therapy are crucial. WHO's recent guidelines used the findings of this comprehensive network meta-analyses, and HIV programmes could consider adopting or adapting these interventions according to resource availability and programme outcomes.