Assessing adherence in Thai patients taking combination antiretroviral therapy

Abstract

In settings where medications and viral load (VL) monitoring are limited by cost, clinicians need reliable ways to assess patient adherence to therapy. We assessed sensitivity and specificity of two self-reported adherence tools (a visual analogue scale [VAS] and the CASE [Center for Adherence Support Evaluation] adherence index), against a standard of detectable VL, with 288 patients from three sites in Thailand. We also assessed predictors of non-adherence. The sensitivity and specificity of the VAS <95% and CASE adherence index ≤11 against a VL >50 copies/mL were 26% and 90%, 19% and 95%, respectively. Against a VL ≥1000 copies/mL sensitivities increased to 55% and 36%, respectively, and specificities were unchanged. Attending a clinic not staffed by HIV specialists (odds ratio [OR] 3.14; 95% confidence interval [CI] 1.19-8.34) and being educated to primary school level or less (OR 2.24; 95% CI 1.01-4.94) were associated with self-reported adherence <95% on the VAS in multivariate analysis. Adherence assessed by the VAS was a more accurate predictor of detectable VL. Policy-makers in resource-limited settings should ensure that treatment centres are staffed with well-trained personnel aware of the importance of good patient adherence.

Pharmacy refill adherence outperforms self-reported methods in predicting HIV therapy outcome in resource-limited settings

“…The dose response relationship between pharmacy refill adherence and virological outcome has also been observed in previous studies [ 10 , 23 , 33 ]. Increasing the virological failure threshold to a viral load > 1,000 copies/mL led to an increase of sensitivity and specificity, confirming previous observation [ 34 ]. While this is to be expected, given that lack of adherence will result in lack of virus control, the more relevant clinical cut-off remains the lower cut-off of 400 copies/ml, which was more related to residual replication of partially-resistant virus under drug selective pressure.…”

Treatment Outcomes and Resistance Patterns of Children and Adolescents on Second-Line Antiretroviral Therapy in Asia

“…Although adherence monitoring is a critical tool to promote ART success, 1,27 different adherence assessment methods may not be sensitive enough to identify patients at risk of VF. 28 Providing effective adherence support is more challenging with children and adolescents because of issues such as limited drug formulations, reliance on caretakers to supervise taking medicines, and pill fatigue associated with life-long therapy. High pill burden and increased medicine frequency are known barriers to adherence, 29 and second-line regimens often require more pills more often than first-line ART.…”

Adherence to antiretroviral therapy during pregnancy and the first year postpartum among HIV-positive women in Ukraine

“…Answers to three questions (on difficulty taking medications on time, frequency of missed doses, and timing of last missed dose) give a score of between 3 and 16, with higher scores indicating better adherence [ 27 ]. Previous studies validating this tool against viral load have determined best score cut-offs for defining ‘poor’ ART adherence to be ≤10 [ 27 ], ≤11 [ 28 ] and ≤12 [ 29 ]; in this study, a score of ≤11 was chosen as it showed the greatest association with viral load measures in validation analyses (data not shown). Responses were also categorised according to whether any missed doses were reported (one potentially valid approach [ 30 ]); ‘≥1 missed dose’ referred to the whole of pregnancy in the antenatal survey, and the preceding four weeks in the postnatal survey.…”