Treatment and Prevention of HIV Through Highly Active Antiretroviral Therapy
AIDS has long been a worldwide problem as many people have been affected, directly or indirectly by this disease. Statistics show that by the latter part of 2009, there were an estimated 3.3 million people who were already affected by HIV/AIDS. There were already 24 million who died because of AIDS and there were 2.6 million people that were newly-affected by this disease.
By the year 2010, there was already progress in stopping AIDS through the use of Highly Active Antiretroviral Therapy (HAART). Recent studies have shown that using HAART would help in preventing and treating HIV. This progress is now being threatened as the Joint United Nations Programme on HIV/AIDS (UNAIDS) reported a 10% drop in funding from the year 2009-2010. Both the US government and European governments expressed their reduction of funding commitments in the worldwide fight against AIDS.
The preventive value of HAART has now been definitively proven in the context of serodiscordant couples, where the immediate use of HAART by the partner with HIV has led to a relative reduction of 96% in the number of linked HIV-1 transmissions, as compared with delayed therapy in a landmark randomized trial. While this result was found solely in serodiscordant heterosexual couples, the basic mechanism of HAART reducing HIV-1-RNA to undetectable levels in blood, genital secretions, and breast milk applies to all modes of transmission. As such, similar protective benefits have been reported among injection drug users in Vancouver, British Columbia, Canada , and Baltimore, Maryland, US, as well as population-based studies.
Current Evidence on the Cost-Effectiveness of HAART and HIV Testing and Prevention Strategies
HAART has long been deemed to be a cost-effective intervention, as it is effective in reducing morbidity and mortality and increasing life-years and quality-adjusted life years (QALYs) gained. However, HAART is associated with substantial up-front costs, and therefore, there has been some lingering ambivalence regarding the expansion of HAART coverage. Indeed, waiting lists to access HAART continue to be a recurrent theme in North America and in resource-limited settings. This is to a large extent based on an incomplete assessment of the true cost-effectiveness of HAART roll out, as illustrated by a recent systematic review. While 89.7% of studies deemed HAART to be cost-effective, only 54.2% of the counseling, testing, and referral strategies evaluated were found to be cost-effective by commonly used thresholds in economic evaluation. Notably, the majority of these studies focused solely on the patient-centered benefits of HAART use. As such, they did not consider the now abundantly documented secondary benefits of HAART, chief among them the impact of HAART on HIV transmission. The additional return on the investment generated by decreases in HIV transmission associated with the use of HAART markedly enhances the cost-effectiveness of the overall expanded roll out of HAART strategy. Consequently, it is likely that the overall cost-effectiveness of HAART roll out was significantly underestimated in the majority of these studies. The evidence is clear: treatment prevents morbidity, mortality, and transmission. From this point on, we argue that these three endpoints should be considered together when evaluating the cost-effectiveness of HAART.
Moving Forward
As we move forward, additional endpoints will need to be captured to fully understand the economic impact of HAART expansion. For instance, HAART is now accepted as a highly effective means to prevent tuberculosis [14]. Expanded treatment will also prevent orphanhood, which also carries a substantial economic burden. One study found that the annual costs of childcare in Rwanda and Malawi were equal to or greater than the annual per capita GDP in those countries. Finally, HAART will also have a positive impact on productivity, particularly in Africa, where AIDS was conservatively estimated to have reduced GDP growth rates by 2%-4% per year in one study.
While challenges in implementation of early detection programs exist, particularly in light of the high risk of transmission in acute and early HIV infection, the impact of HAART on HIV transmission has nonetheless profoundly shifted the cost-effectiveness of this intervention. As a result, the strategic value of expanded HIV testing and expansion of HAART coverage has dramatically increased. We believe this should open the door for wide-scale implementation of "Seek, Test, Treat and Retain" programs as a means to control HIV and AIDS-related morbidity, mortality, and transmission at once.