Cost Savings From Preventing HIV Infection

"Effective treatment has increased life expectancy after HIV infection, and deaths from non-AIDS-related causes now exceed deaths from AIDS for those with HIV in the US [35]. Medical costs of treating HIV-infected individuals as they age now include costs of both HIV-related and HIV-unrelated medical care. We estimated the medical cost saved by averting one HIV infection in the United States, taking into account the costs that would have been incurred by similar at-risk individuals in the absence of HIV infection. We project discounted medical cost savings of $229,800 by permanently averting one HIV infection based on current care patterns in the US and $49,500 if one HIV infection is delayed by 5 years. Our analysis shows that as HIV care becomes more effective, the cost avoided by averting one HIV infection also increases. Improved care is cost-effective by accepted standards in the US, it is not cost-saving [36]. The added years of life, however, result in additional costs for treatment that would not have occurred in the absence of an infection.

"Our projections of lifetime medical costs for HIV-infected individuals of $326,500 in the base case and $435,200 in the optimal care case are comparable to recent model-based estimates of lifetime costs for individuals in the US entering care with CD4 201–350/μl ($332,300 in 2012 US dollars) and >500/μl ($443,000) respectively [37], and costs from entry into care (not shown) are consistent with previous estimates of these costs in France using the CEPAC model [38]. Our projection of medical cost savings of $229,800 is substantially lower than the previous estimate of $303,100 in 2004 US dollars ($361,400 in 2012 US dollars) [7] for several reasons. First, we now account for medical costs that would have been incurred in the absence of an HIV infection. Second, our previous analysis did not adjust mortality for risk group characteristics that lower average life expectancy [23], thereby reducing costs, nor did they adjust costs for health service utilization by different risk groups. Our life expectancy estimates are lower than two other recent model-based analyses in the United States and the United Kingdom [37, 39], likely reflecting the race/ethnicity and risk-category mortality effects in our model. Our results are consistent with these models, however, in projecting substantial life expectancy losses associated both with becoming HIV infected and with delayed initiation of treatment after infection.

"Consistent with other analyses [7, 37], we found that ART medications represent the largest component of cost for HIV-infected individuals. We found that non-HIV chronic care medications represent a substantial component of cost as well, emphasizing the significant cost of managing non-HIV comorbidities in an aging HIV-infected population [13, 40]. These comorbidities are frequently managed by HIV primary care providers [41]. Our results are somewhat sensitive to assumptions about future use of generic HIV drugs in the US. This points to the potential importance of future availability of generic drugs in lowering the cost of HIV care, depending on regimens selected and adherence [32].

"Our analysis also indicates that the value of HIV primary prevention may be greater when the effects of preventing secondary transmission to HIV-uninfected partners are taken into account, which would increase the value of interventions targeting individuals at high risk of transmitting to multiple partners. The magnitude of this impact is greater the longer individuals remain uninfected after avoiding a secondary transmission. The current relatively stable HIV incidence trends in the US [15] suggest these uninfected partners are at high risk for eventual HIV infection. If the probabilities of secondary transmission we used already take into account this additional risk, the value of primary prevention would be even higher."