Randomized clinical trial of HIV treatment adherence counseling interventions for people living with HIV and limited health literacy.

Background: Limited health literacy is a known barrier to medication adherence among people living with HIV. Adherence improvement interventions are urgently needed for this vulnerable population.

Purpose: This study tested the efficacy of a pictograph-guided adherence skills-building counseling intervention for limited literacy adults living with HIV.

Methods: Men and women living with HIV and receiving antiretroviral therapy (N = 446) who scored <90% correct on a test of functional health literacy were partitioned into marginal and lower literacy groups and randomly allocated to 1 of 3 adherence-counseling conditions: (1) pictograph-guided adherence counseling, (2) standard adherence counseling, or (3) general health improvement counseling. Participants were followed for 9 months postintervention with unannounced pill count adherence and blood plasma viral load as primary end points.

Results: Preliminary analyses demonstrated the integrity of the trial and >90% of participants were retained. Generalized estimating equations showed significant interactions between counseling conditions and levels of participant health literacy across outcomes. Participants with marginal health literacy in the pictograph-guided and standard-counseling conditions demonstrated greater adherence and undetectable HIV viral loads compared with general health counseling. In contrast and contrary to hypotheses, participants with lower health literacy skills in the general health improvement counseling demonstrated greater adherence compared with the 2 adherence counseling conditions.

Conclusions: Patients with marginal literacy skills benefit from adherence counseling regardless of pictographic tailoring, and patients with lower literacy skills may require more intensive or provider-directed interventions.