Background: Non-adherence to combination Antiretroviral Therapy (cART)
is common and can have substantial clinical and economic consequences. The theory- and
evidence-based Adherence Improving self-Management Strategy (AIMS) has demonstrated the ability
to improve adherence and clinical outcomes in earlier trials. However, its cost-effectiveness
is not yet investigated. Methods: We examined the cost-effectiveness of AIMS compared to
treatment-as-usual from a societal perspective, with a time horizon of one year. Primary
outcome measures were cost per reduction in log viral load (a health-related outcome) and cost
per quality-adjusted life-year (QALY). Findings: Twenty-one HIV-nurses in seven Dutch
HIV-clinics randomized 223 patients (110 treatment-experienced and 113 treatment-initiating
patients). The probability that AIMS is cost-effective using log viral load as outcome
parameter was between 55% to 95%. For the analysis using QALYs as the outcome parameter, the
cost-effectiveness probability was between 80% and 55%. Discussion: The results from the
cost-effectiveness analyses strongly indicate that the AIMS-intervention is cost-effective,
even within the one-year trial period. A model-based economic evaluation with a longer time
horizon should reveal how cost-effective AIMS is in the long run.
