Clinical and Economic Implications of Non-Adherence to HAART in HIV Infection

Highly active antiretroviral therapy (HAART) has dramatically altered the natural history of HIV disease. Studies demonstrate that >=95% adherence is necessary to garner the full benefits of HAART. However, appropriate adherence to treatment is difficult and challenging. This paper provides an overview of potential clinical and economic outcomes associated with poor adherence to HAART. Since there are no studies exploring the costs associated with poor adherence to HAART, we discuss potential direct and indirect costs accrued with more frequent treatment failures, selection of resistant strains, increased hospitalizations and a faster progression to AIDS associated with poor adherence to HAART. Additionally, we review studies of interventions and strategies to improve adherence to HAART. Although, single-focus interventions have enhanced the chances of achieving viral suppression by 10 to 23%, the literature has demonstrated that for long-term treatments, programs employing diverse interventions that continue over time are more effective. Under constrained healthcare budgets, government, healthcare managers and policy makers require accurate and timely information concerning the cost effectiveness of adherence intervention programs. We discuss considerations in determining the cost effectiveness of an adherence intervention program.