Estimating the impact of antiretroviral therapy: regional and global estimates of life-years gained among adults
- 1UNAIDS, Evidence, Strategy and Results Department, Geneva, Switzerland
- 2Futures Institute, Glastonbury, Connecticut, USA
- 3HIV Department, World Health Organization, Geneva, Switzerland
- Correspondence to Dr Mary Mahy, UNAIDS, 20 avenue Appia, 1211 Geneva 27, Switzerland;
Contributors MM developed the concept of the paper, drafted the text and conducted the analysis; JS developed Spectrum and provided comments on the manuscript; KS provided comments on the manuscript and supervised the country estimates process; RS provided comments on the manuscript and JMT provided comments on the manuscript.
- Accepted 7 October 2010
Objective An estimated 4.9 million adults received antiretroviral therapy (ART) in low and middle income countries in 2009. A further estimated 700 000 adults received ART in high-income countries. The impact of providing ART is not often quantifiable due to limited monitoring systems. One measure, life-years gained, provides a standardised measure that shows the survival impact of ART on the population while controlling for variations in underlying survival. Measuring life-years gained allows a comparison of the impact of ART between regions.
Methods Using the Spectrum computer package, two different scenarios were created for 151 countries. One scenario describes the results of providing adults with ART as reported by countries between 1995 and 2009, the second scenario describes a situation in which no ART was provided to adults living with HIV between 1995 and 2009. The difference in the number of life-years accrued among adults in the two scenarios is compared and summarised by geographical region.
Results An estimated 14.4 million life-years have been gained among adults globally between 1995 and 2009 as a result of ART. 54 % of these years were gained in western Europe and North America, where ART has been available for over 10 years. In recent years the growth in life-years has occurred more rapidly in sub-Saharan Africa and Asia.
Discussion The substantial impact of ART described here provides evidence to argue for continued support of sustainable ART programmes in low and middle-income countries. Strengthening ART monitoring systems and mortality surveillance in low and middle-income countries will make this evidence more accessible to programme managers.
Competing interests None.
Provenance and peer review Not commissioned; externally peer reviewed.
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