Background: Opioid agonist therapies with methadone are associated with higher levels of adherence to antiretroviral therapy (ART); yet, no studies have explored factors associated with optimal ART levels in HIV-positive patients on methadone maintenance treatment, including explanatory pathways using mediation analysis.
Setting: Participants included 121 HIV-positive, methadone-maintained patients who reported HIV-risk behaviors and were taking ART.
Methods: Participants were assessed using an audio computer-assisted self-interview. Multivariable logistic regression was used to identify significant correlates and PROCESS macro to test the explanatory pathway (ie, mediational effect) for optimal ART adherence.
Results: Among 121 participants, almost 40% reported suboptimal adherence to ART. Optimal ART adherence was significantly associated with being virally suppressed [adjusted odds ratio (aOR) = 6.470, P = 0.038], higher motivation to adhere to ART (aOR = 1.171, P = 0.011), and lower anticipated HIV-related stigma (aOR = 0.384, P = 0.015). Furthermore, results revealed an indirect effect of motivation on the relationship between HIV stigma and ART adherence (effect = -0.121, P = 0.043), thus supporting the mediation effect.
Conclusions: Our findings underscore the complexities surrounding ART adherence, even in patients on methadone maintenance treatment. These findings provide insights on how to more effectively intervene to optimize HIV treatment outcomes, including HIV treatment-as-prevention initiatives, in methadone-maintained patients.