Cost-Effectiveness of Initial Adherence to Antiretroviral Therapy among HIV Infected Patients in Belo Horizonte, Brazil

Abstract

Background: In Brazil, there is free antiretroviral (ARV) distribution to patients with HIV disease by the National Health System. Adherence to the treatment is one of the main factors that health services can manage to increase the effectiveness of the ARV medication. The aim of this study is to evaluate the cost-effectiveness of initial adherence to the ARV therapy and to identify factors that influence patient s costs and global evolution. Methods: Prospective study of HIV infected patients receiving their first ARV prescription in two public referral centers to HIV/Aids, Brazil. The non-adherence was defined as the intake of <95% of the prescribed doses for 3 days prior to the first follow-up visit. A cost-effectiveness ratio was calculated for either groups, the adherent and the non-adherent. Univariate and multivariate analysis were performed using multiple linear and binary logistic regression models. Results: 79.7% of the 197 participants was adherent to the ARV treatment and the ratio cost-effectiveness obtained for this group (2,667.67 euros) was smaller than the ratio observed among the non-adherent group. Multivariate analysis (p<0.05) showed that adherence to ARV therapy and use of protease inhibitors in the treatment were associated with higher direct cost of care. The favorable global evolution was associated with being asymptomatic, TCD4+ linphocyte count >200 cels/mm3 and be adherent to the ARV treatment. Conclusions: The observed results supported the ARV therapy as a cost-effective intervention. However, low adherence increases the risk of therapeutic failure and illness progression that results in a negative impact on the cost-efectiveness of the ARV therapy.