Early warning indicators for first-line virologic failure independent of adherence measures in a South African urban clinic

Abstract

We sought to develop individual-level Early Warning Indicators (EWI) of virologic failure (VF) for clinicians to use during routine care complementing WHO population-level EWI. A case-control study was conducted at a Durban clinic. Patients after ≥ 5 months of first-line antiretroviral therapy (ART) were defined as cases if they had VF [HIV-1 viral load (VL)>1000 copies/mL] and controls (2:1) if they had VL ≤ 1000 copies/mL. Pharmacy refills and pill counts were used as adherence measures. Participants responded to a questionnaire including validated psychosocial and symptom scales. Data were also collected from the medical record. Multivariable logistic regression models of VF included factors associated with VF (p<0.05) in univariable analyses. We enrolled 158 cases and 300 controls. In the final multivariable model, male gender, not having an active religious faith, practicing unsafe sex, having a family member with HIV, not being pleased with the clinic experience, symptoms of depression, fatigue, or rash, low CD4 counts, family recommending HIV care, and using a TV/radio as ART reminders (compared to mobile phones) were associated with VF independent of adherence measures. In this setting, we identified several key individual-level EWI associated with VF including novel psychosocial factors independent of adherence measures.

Figures

FIG. 1.

Receiver operator characteristic curves for multivariable models 1–5 (A–E).

FIG. 2.

Correlation between Access and Adherence variables for cases and controls. (Color for this image can be found at www.liebertpub.com/apc.)

FIG. 3.

Schema of social, behavioral and clinical factors related to virologic response for individuals receiving antiretroviral therapy (ART). Pill adherence is necessary for viral load (VL) suppression; however, access to ART is neither necessary nor sufficient. Individuals can obtain ART from family or friends and may not swallow pills despite obtaining them. Socioeconomic factors (i.e., transportation to clinic) and co-morbid illnesses have a more direct effect on ART access. Likewise, concomitant medications and psychosocial factors (i.e., stigma, disclosure, and depression) are more directly associated with ART adherence but also impact ART access. Institutional (healthcare, religious, governmental), community (neighborhood, dyadic) and societal (cultural, infrastructure, policy) factors have more global impact at all lower levels in this paradigm. (Color for this image can be found at www.liebertpub.com/apc.)