Interactive effects of neurocognitive impairment and substance use on antiretroviral non-adherence in HIV disease.

While numerous studies have established the adverse independent effects of clinical conditions including neurocognitive dysfunction, psychiatric illness, and substance abuse/dependence on medication adherence among HIV-infected adults, fewer have studied their interactive effects. The current study examined this issue among 204 HIV-infected participants based upon current neurocognitive functioning and DSM-IV-diagnosed psychiatric illness and current substance abuse or dependence. Results confirmed that participants with any of these risk factors demonstrated poorer adherence than individuals with no risk factors. A neurocognitive status × substance abuse/dependence interaction was also identified such that participants with impaired neurocognition and a co-occurring substance abuse/dependence diagnosis demonstrated the poorest adherence. Results confirm the deleterious impact of these risk factors in isolation and also identify a specific interactive effect for individuals with comorbid neurocognitive impairment and a substance abuse/dependence disorder. Findings highlight the need for interventions that simultaneously address these problems.