Investigating the potentially important role of psychological flexibility in adherence to antiretroviral therapy in people living with HIV

Antiretroviral therapy (ART) has significantly improved immune health and survival rates in HIV, but these outcomes rely on near perfect adherence. While many psychosocial factors are related to sub-optimal adherence, effectiveness of associated interventions are modest or inconsistent. The Psychological Flexibility (PF) model underlying Acceptance and Commitment Therapy (ACT) identifies a core set of broadly applicable transdiagnostic processes that may be useful to explain and improve non-adherence. However, PF has not previously been examined in relation to ART adherence. Therefore, this cross-sectional study (n = 275) explored relationships between PF and intentional/unintentional ART non-adherence in people with HIV. Adults with HIV prescribed ART were recruited online. Participants completed online questionnaires assessing self-reported PF, adherence and emotional and general functioning. Logistic regressions examined whether PF processes were associated with intentional/unintentional non-adherence. Fifty-eight percent of participants were classified as nonadherent according to the Medication Adherence Rating Scale, of which 41.0% reported intentional and 94.0% unintentional non-adherence. Correlations between PF and adherence were small. PF did not significantly explain intentional/unintentional non-adherence after controlling for demographic and disease factors. Further clarification of the utility of PF in understanding ART non-adherence is warranted using prospective or experimental designs in conjunction with more objective adherence measures.