Featured HIV Publication - Cost-effectiveness analysis of strategies to monitor adults on antiretroviral treatment

10 December 2013

WHO's 2013 revisions to its Consolidated Guidelines on antiretroviral drugs recommend routine viral load monitoring, rather than clinical or immunological monitoring, as the preferred monitoring approach on the basis of clinical evidence. However, HIV programmes in resource-limited settings require guidance on the most cost-effective use of resources in view of other competing priorities such as expansion of antiretroviral therapy coverage.

Cost-effectiveness of different strategies to monitor adults on antiretroviral treatment: a combined analysis of three mathematical models

Daniel Keebler, Paul Revill, Scott Braithwaite, Prof Andrew Phillips, Nello Blaser, Annick Borquez, Valentina Cambiano, Andrea Ciaranello, Janne Estill, Richard Gray, Andrew Hill, Olivia Keiser, Jason Kessler, Nicolas A Menzies, Kimberly A Nucifora, Luisa Salazar Vizcaya, Simon Walker, Alex Welte, Philippa Easterbrook, Meg Doherty, Gottfried Hirnschall and Timothy B Hallett

In this analysis the team assessed the cost-effectiveness of alternative patient monitoring strategies. They evaluated a range of monitoring strategies, including clinical, CD4 cell count, and viral load monitoring, alone and together, at different frequencies and with different criteria for switching to second-line therapies. They used three independently constructed and validated models simultaneously. They estimated costs on the basis of resource use projected in the models and associated unit costs and quantified impact as disability-adjusted life years (DALYs) averted. They also compared alternatives using incremental cost-effectiveness analysis.

All models show that clinical monitoring delivers significant benefit compared with a hypothetical baseline scenario with no monitoring or switching. Regular CD4 cell count monitoring confers a benefit over clinical monitoring alone, at an incremental cost that makes it affordable in more settings than viral load monitoring, which is currently more expensive. Viral load monitoring without CD4 cell count every 6—12 months provides the greatest reductions in morbidity and mortality, but incurs a high cost per DALY averted, resulting in lost opportunities to generate health gains if implemented instead of increasing antiretroviral therapy coverage or expanding antiretroviral therapy eligibility.

The priority for HIV programmes should be to expand antiretroviral therapy coverage, firstly at CD4 cell count lower than 350 cells per μL, and then at a CD4 cell count lower than 500 cells per μL, using lower-cost clinical or CD4 monitoring. At current costs, viral load monitoring should be considered only after high antiretroviral therapy coverage has been achieved. Point-of-care technologies and other factors reducing costs might make viral load monitoring more affordable in future.

Read the full article in The Lancet Global Health