Adherence to combination antiretroviral therapy (cART ) plays an important role on treatment outcomes. The TREAT Asia Studies to Evaluate Resistance – Monitoring Cohort Study (TASER-M) collects patients’ adherence based on a Visual Analogue Scale. The aim of this analysis was to assess the rates of, and factors associated with, suboptimal adherence in the first 24 months of initial cART in Asian patients.
Methods: Suboptimal adherence was defined as reported adherence <100%. Follow-up time started from cART initiation and censored at 24 months, lost to follow up, death, treatment switch due to any reason, or treatment cessation of more than 14 days. Follow-up time was divided into 6 monthly intervals: 0-6, 6-12,12-18 and 18-24 months. Factors associated with suboptimal adherence was analysed using generalised estimating equations. results: 1316 patients across 5 countries in Asia were included. The rates of suboptimal adherence for time intervals 0-6, 6-12, 12-18 and 18-24 months were 26%, 17%, 12% and 10%, respectively. In multivariate analyses, sites with average adherence assessment of >2 times/year were associated with decreased odds of suboptimal adherence (OR=0.7, 95%CI(0.55-0.90), p=0.006). Compared to patients with heterosexual exposure, injecting drug users were almost twice as likely to report <100% adherence (OR=1.92, 95%CI(1.23-3.00), p=0.004), while the odds in homosexual individuals was halved (OR=0.52, 95%CI(0.38-0.71), p<0.001). Patients taking NRTI+PI as their initial regimen had a 64% reduction in suboptimal adherence (OR=0.36, 95%CI(0.20-0.67), p=0.001) compared to those on NRTI+NNRTI. Increasing time interval was associated with decreasing odds (ORs=0.59, 0.40 and 0.35, respectively, all p<0.001).
Conclusions: Suboptimal adherence was higher with injecting drug users, and lower with homosexual exposure. Increased adherence assessments was associated with reduction in suboptimal adherence, possibly reflecting site resourcing for patient counselling. PI based initial regimen and longer time intervals were associated with improved adherence.