What is known and objective: Adherence to highly active antiretroviral treatment (HAART) is an important predictive factor of treatment outcome. Medication regimen complexity can be one of the main causes of non-adherence. Thus, treatment simplification is a key strategy in the development of antiretroviral therapy. The aim of this study was to determine the influence of adding etravirine on complexity index and patients' perceived complexity of their treatment regimen.
Methods: We conducted a prospective two-centre observational study. Patients on etravirine-based therapy, for at least 6 months, who came personally to pharmacy departments for a drug refill from February to July 2012 were included. Data were collected for the current etravirine-based HAART and for the previous HAART without etravirine. The main variables were complexity index and patients' perceived complexity. We also evaluated the adherence during the 6 months before and after the introduction of etravirine into HAART. The complexity index was based on a score which takes into account the number of pills per day, the dosing schedule, the dosage form and any specific instructions linked to use of the drug. To evaluate the patients' perceived complexity of their current and previous HAART, patients were asked to assign a mark on a visual analogue scale ranging from 0 (minimum) to 10 (maximum). We assessed the differences in the variables collected between the current and previous antiretroviral therapy. Finally, we carried out a correlation analysis between the complexity index and the patients' perceived complexity.
Results and discussion: Eighty patients were included. The complexity index was significantly reduced after the addition of etravirine to HAART (P = 0·035). Perceived complexity was also reduced (P = 0·015). After the introduction of the drug, the proportion of adherent patients increased from 65% to 81·3% (P = 0·002). The correlation between the complexity index and the patients' perceived complexity was positive (r = 0·594). The correlation increased (r = 0·696) when the difference between the complexity index before and after the introduction of etravirine in HAART grew.
What is new and conclusion: The addition of etravirine to HAART results in a significant reduction in complexity index and patients' perceived complexity of their therapy. These changes were associated with better adherence to treatment.
Keywords: HIV; etravirine; medication adherence; regimen complexity.
© 2013 John Wiley & Sons Ltd.