Abstract
The visual-analogue scale (VAS), Likert item (rating scale), pills identification test (PIT), and medication possession ratio (MPR) provide estimates of antiretroviral therapy (ART) adherence which correlate with HIV viral suppression. These simple adherence measures are inexpensive and easy to administer; however, require validation and adjustment prior to implementation. The objective of this study was to define the optimal adherence assessment measure in Namibia to identify patients at risk for sub-optimal adherence and poor virologic response 6 months after ART initiation. We conducted a cross-sectional survey in HIV-infected adults receiving ART for 6–12 months prior to the adherence assessment. Adherence measures included 30-day VAS, 30-day Likert item, self-reported treatment interruptions, PIT, and MPR. Association of adherence measures with 6-month HIV-1 RNA level was assessed using two thresholds (1000 copies/mL and 5000 copies/mL). Adherence was assessed in 236 patients, mean age 37.3 years, 54% female. Mean adherence was 98.1% by 30-day VAS, 84.7% by 30-day Likert item, 97.0% by self-reported treatment interruptions, 90.6% by PIT, and 98.8% by MPR. Agreement between adherence measures was poor using kappa statistic. 76% had HIV-1 RNA <1000 copies/ml, and 88% had HIV-1 RNA <5000 copies/ml. MPR (continuous) was associated with viral suppression <5000 copies/ml (p = 0.036). MPR <75% was associated with virologic failure at ≥5000 copies/ml with OR 3.89 (1.24, 12.21), p = 0.013. Adherence was high with all measures. Only MPR, was associated with short-term virologic response, suggesting its cross-culturally utility for early identification of patients at high risk for virologic failure.
Highlights
As of December 2011, over 8 million people infected with HIV were receiving antiretroviral therapy (ART) in low- and middleincome countries which represents a 26-fold increase since 2003 [1]
Adherence as measured by a 30-day visual-analogue scale (VAS) [16,17], Likert item, pills identification test (PIT) [18], and medication possession ratio (MPR) [6,19,20,21] have been shown to be associated with viral suppression
The level of adherence observed in the three public ART delivery sites in Windhoek, Namibia was high as estimated by all five adherence measures
Summary
As of December 2011, over 8 million people infected with HIV were receiving antiretroviral therapy (ART) in low- and middleincome countries which represents a 26-fold increase since 2003 [1]. Adherence as measured by a 30-day visual-analogue scale (VAS) [16,17], Likert item (rating scale), pills identification test (PIT) [18], and medication possession ratio (MPR) [6,19,20,21] have been shown to be associated with viral suppression (adherence measures defined in Methods Section). These simple adherence measures are inexpensive and easy to administer. The VAS, Likert item, PIT, and MPR have been demonstrated to be valid measures of adherence, they require validation and adjustment prior to implementation to account for local cultural and linguistic factors
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
