Cost effectiveness of prophylaxis for opportunistic infections in AIDS. An overview and methodological discussion

Dramatic progress has recently been made in defining the pathogenesis and treatment of HIV infection. For the first time in the history of the AIDS epidemic, clinicians have at their disposal an understanding of the replication kinetics of HIV, reliable assays to measure viral load, an increasing number of effective agents to suppress viral replication and to reverse the process of immune system destruction, and a range of options for the treatment and prophylaxis of most of the major opportunistic infections in HIV disease. These remarkable advances are not without their costs, however. New antiretroviral therapies and opportunistic infection prophylaxis regimens impose considerable financial strain on public and private budgets for HIV patient care. They force decision-makers to confront a variety of competing considerations, including issues of length and quality of life, the risks of adverse effects and toxicities, and the dangers of promoting resistance. Questions regarding the continued appropriateness and efficiency of opportunistic infection prevention have prompted increased interest in studies of the cost effectiveness of HIV patient care. In this article, we reviewed the literature on the economic evaluation of prophylaxis for HIV-related complications. Section 1 provides background on recent scientific and clinical advances. Section 2 reviews the state-of-the-art understanding of the cost effectiveness of prophylaxis against specific opportunistic infections. Section 3 broadens the discussion to consider the more general question of optimal allocation of prophylaxis resources across competing opportunistic infections. In Section 4, we briefly examined the influence of cost-effectiveness evaluations on the development and refinement of clinical guidelines for HIV-related opportunistic infection prevention in the US. Section 5 presents some of the methodological challenges that arise in applying the methods of cost-effectiveness analysis to the particular case of opportunistic infection prevention in AIDS. We close, in Section 6, with a comment on directions for further research.