Economic models of antiretroviral therapy: searching for the optimal strategy

The diffusion of protease inhibitors and non-nucleoside reverse transcriptase inhibitors in the US in 1996 and 1997 reduced the number of deaths attributable to HIV disease and changed the way we think about the illness. Today, HIV disease may be deemed a fairly expensive chronic condition rather than an intolerably expensive fatal illness. Although most studies have found that patients receiving new drug therapies are hospitalised less frequently than patients who received early drug therapies, it is unclear whether the diffusion of new drug therapies has increased or decreased the annual cost of care. However, it is evident that the diffusion of new drug therapies has increased the lifetime cost of care. Analysts rely on models to simulate the course and cost of HIV disease. This study reviews the evolution of these models, paying particular attention to how these models estimate the cost of care. The primary findings of this review are that the economic data used in these models are often too imprecise to accurately identify the cost of each disease stage and are almost always outdated. Moreover, it was found that estimates of drug costs in these models may not accurately reflect actual expenditures.