Comparative effectiveness of HIV testing and treatment in highly endemic regions

Abstract

Background: Universal testing and treatment holds promise for reducing the burden of human immunodeficiency virus (HIV) in sub-Saharan Africa, but linkage from testing to treatment sites and retention in care are inadequate.

Methods: We developed a simulation of the HIV epidemic and HIV disease progression in South Africa to compare the outcomes of the present HIV treatment campaign (status quo) with 4 HIV testing and treating strategies that increase access to antiretroviral therapy: (1) universal testing and treatment without changes in linkage to care and loss to follow-up; (2) universal testing and treatment with improved linkage to care; (3) universal testing and treatment with reduced loss to follow-up; and (4) comprehensive HIV care with universal testing and treatment, improved linkage to care, and reduced loss to follow-up. The main outcome measures were survival benefits, new HIV infections, and HIV prevalence.

Results: Compared with the status quo strategy, universal testing and treatment (1) was associated with a mean (95% uncertainty bounds) life expectancy gain of 12.0 months (11.3-12.2 months), and 35.3% (32.7%-37.5%) fewer HIV infections over a 10-year time horizon. Improved linkage to care (2), prevention of loss to follow-up (3), and comprehensive HIV care (4) provided substantial additional benefits: life expectancy gains compared with the status quo strategy were 16.1, 18.6, and 22.2 months, and new infections were 55.5%, 51.4%, and 73.2% lower, respectively. In sensitivity analysis, comprehensive HIV care reduced new infections by 69.7% to 76.7% under a broad set of assumptions.

Conclusions: Universal testing and treatment with current levels of linkage to care and loss to follow-up could substantially reduce the HIV death toll and new HIV infections. However, increasing linkage to care and preventing loss to follow-up provides nearly twice the benefits of universal testing and treatment alone.

Figure 1

Estimated deaths from HIV over 10 years in South Africa for different HIV testing and treatment strategies. A comparison of the total number of HIV-related deaths over 10 years, by strategy, scaled to South Africa. The error bars represent the 95% confidence bounds from the probabilistic sensitivity analysis.

Figure 2

Projected HIV prevalence in South Africa for different HIV testing and treatment strategies.

Figure 3

Sensitivity analysis of the mortality benefits and reduction in transmission from gradual improvements in linkage to care and prevention of LTFU. Panel A shows the mortality benefits and panel B the reduction in new HIV infections. Each line represents the benefit compared with a universal testing and treatment alone. The relative benefits for improved linkage range over 67%–100% linkage, and for LTFU from 20%-0% loss. The Comprehensive strategy represents simultaneous improvements in linkage and prevention of LTFU. For example, universal testing and treatment with improved linkage to 80% results in a gain of about 2.5 months of life expectancy, or 15% improvement, over universal testing and treatment alone.