- Category: HIV Treatment
- Published on Thursday, 12 December 2013 00:00
- Written by Liz Highleyman
Widespread use of effective antiretroviral therapy (ART) has led to "massive benefits" in hard-hit South Africa, saving an estimated 2.8 million life-years by 2012, and potentially up to 22 million years over the lifetime of treated individuals, according to a modeling study described in the December 3, 2013, advance edition of the Journal of Infectious Diseases.
Michael April and Rachel Walensky from Harvard University and colleagues sought to quantify the survival benefits of ART in South Africa since 2004.
South Africa has the world’s largest HIV epidemic, with an estimated 5.6 million people infected in 2011, according to UNAIDS. While half of people with HIV are eligible for ART based on current guidelines, one-third remain untreated, the study authors noted as background.
The researchers used the Cost-Effectiveness of Preventing AIDS Complications-International (CEPAC) mathematical model to simulate 8 cohorts of people with HIV initiating ART each year during 2004-2011.
The estimated number of people starting ART rose from 50,100 in 2004 to 557,300 in 2011, for a total of 2,222,700 during the entire period. The model assumed that patients had relatively low CD4 T-cell counts at ART initiation (mean 112-178 cells/mm3), 78% achieved viral suppression after 24 weeks of therapy, 55%-71% stayed on treatment for 36 months, and 2.4% had access to second-line ART if needed.
- Lifetime survival benefits ranged from 9.3 to 10.2 life-years per person across the 8 cohorts.
- Total estimated population lifetime survival benefit for all people starting ART during 2004-2011 was 21.7 million life-years.
- 2.8 million life-years (12.7% of the total) would already have been saved by December 2012.
- By 2030, the number of life-years saved reached:
o 17.9 million under current ART access policies if no new patients start treatment;
o 21.7 million life-years if second-line ART were universally available;
o 23.3 million life-years if 10% more eligible but currently untreated people were linked to care;
o 28.0 million life-years given both universal second-line ART and increased case detection;
o 35.6 million life-years given both universal second-line ART and 84% increased linkage to care.
"We found dramatic past and potential future survival benefits attributable to ART, justifying international support of ART rollout in South Africa," the study authors concluded.
They noted that the 17.9 million life-years expected to be saved under current policies was just half of the benefit that could be gained under the most optimistic scenario of expanded case detection, linkage to care, and universal second-line therapy.
"Realizing the full potential return on investments already made will require that funding sources remain committed to maintaining and expanding resources available for monitoring, retention, and treatment," they emphasized.
In an accompanying editorial, Sten Vermund from the Institute for Global Health noted the "astounding" magnitude of benefit achieved after a period of government denialism and refusal to implement widespread treatment under the leadership of Thabo Mbeki. Vermund also pointed out that benefits may well be even greater than this model predicts given the added impact of treatment as prevention.
"We hope that this study reminds stakeholders of the astounding efficacy of the global ART rollout while simultaneously invigorating efforts to redouble commitments toward expanding the availability of ART," stated lead study author April in a press release issued by journal publisher Oxford University Press.
MD April, R Wood, BK Berkowitz, RP Walensky, et al. The Survival Benefits of Antiretroviral Therapy in South Africa. Journal of Infectious Diseases. December 3, 2013 (Epub ahead of print).
SH Vermund. Massive Benefits of Antiretroviral Therapy in Africa. Journal of Infectious Diseases. December 2013 9 (Epub ahead of print).
Oxford University Press. Study Highlights Massive Benefits of HIV Treatment in South Africa. Press release. December 4, 2013.