Verbal Learning Mediates the Relationship Between Executive Functions and a Laboratory Task of Medication Management in HIV Disease.

Abstract

Impairments in executive functions and learning are common in HIV disease and increase the risk of nonadherence to antiretroviral therapy. The mixed encoding/retrieval profile of HIV-associated deficits in learning and memory is largely driven by dysregulation of prefrontal systems and related executive dysfunction. This study tested the hypothesis that learning may be one pathway by which executive dysfunction disrupts medication management in people living with HIV (PLWH). A total of 195 PLWH completed a performance-based laboratory task of medication management capacity and clinical measures of executive functions, verbal learning and memory, and motor skills. Executive functions were significantly associated with verbal learning and medication management performance. In a model controlling for education, learning significantly mediated the relationship between executive functions and medication management, and this mediation was associated with a small effect size. In particular, executive dysfunction was associated with diminished use of higher-order learning strategies. Alternate models showed that executive functions did not mediate the relationship between learning and medication management nor did motor skills mediate the relationship between executive functions and medication management. PLWH with executive dysfunction may demonstrate difficulty in learning new information, potentially due to ineffective strategy use, which may in turn put them at a higher risk for problems managing their medications in the laboratory. Future studies may wish to investigate whether compensatory neurocognitive training (e.g., using more effective learning strategies) may improve medication management among PLWH.