Karina M. Berg

The goals of this study were to examine the association between pain and antiretroviral adherence and to estimate the mediating effect of adherence self-efficacy and depression symptom severity. Surveys using audio computer-assisted self-interview were conducted among 70 HIV-infected current and former drug users enrolled in a methadone program. We assessed antiretroviral adherence and adherence self-efficacy using questions from the Adult Clinical Trials Group survey. We considered participants adherent if they reported taking at least 95% of prescribed antiretrovirals over the past seven days. We assessed depression symptom severity using the depression subscale of the Brief Symptom Inventory. Participants reported pain of any duration in response to a question from the Brief Pain Inventory. Participants reporting pain were 87% less likely to be classified as adherent compared to those without pain (Unadjusted OR = 0.13, 95%CI: 0.03–0.52). When we examined adherence self-efficacy as a mediator of the relationship between pain and adherence, criteria for partial mediation were met. Adjusting for self-efficacy, the beta coefficient for pain decreased by 23% but the independent relationship between pain and antiretroviral adherence was maintained. Mediation criteria were not met when we examined the mediating effect of depression symptom severity on the relationship between pain and adherence. Adjusting for depression symptom severity, the beta coefficient for pain decreased by 9% and the relationship between pain and antiretroviral adherence remained significant. Our results indicate that neither adherence self-efficacy nor depression symptom severity fully mediated the relationship between pain and adherence. HIV providers should recognize the potential impact of pain on antiretroviral adherence among current and former drug users.

BACKGROUND Successful management of chronic pain with opioid medications requires balancing opioid dependence and addiction with pain relief and restoration of function. Evaluating these risks and benefits is difficult among patients with chronic pain and pre-existing addiction, and the ambiguity is increased for patients on methadone maintenance therapy for opioid dependence. Providers treating both chronic pain and addiction routinely make diagnostic and therapeutic decisions, but decision-making strategies in this context have not been well described. OBJECTIVE Our objective was twofold. We sought first to explore providers’ perceptions of ambiguity, and then to examine their strategies for making diagnostic and treatment decisions to manage chronic pain among patients on methadone maintenance therapy. DESIGN Qualitative semi-structured interviews. SETTING AND PARTICIPANTS We interviewed health-care providers delivering integrated medical care and substance abuse treatment to patients in a methadone maintenance program. RESULTS Providers treating pain and co-morbid addiction described ambiguity in all diagnostic and therapeutic decisions. To cope with this inherent ambiguity, most providers adopted one of two decision-making frameworks, which determined clinical behavior. One framework prioritized addiction treatment by emphasizing the destructive consequences of abusing illicit drugs or prescription medications; the other prioritized pain management by focusing on the destructive consequences of untreated pain. Identification with a decision-making framework shaped providers’ experiences, including their treatment goals, perceptions of treatment risks, pain management strategies, and tolerance of ambiguity. Adherence to one of these two frameworks led to wide variation in pain management practices, which created tension among providers. CONCLUSIONS Providers delivering integrated medical care and substance abuse treatment to patients in a methadone maintenance program found tremendous ambiguity in the management of chronic pain. Most providers adopted one of the two divergent heuristic frameworks we identified, which resulted in significant variations in pain management. To reduce variation and determine best practices, studies should examine clinically relevant endpoints, including pain, illicit drug use, prescription drug abuse, and functional status. Until then, providers managing chronic pain in patients with co-morbid addiction should attempt to reduce tension by acknowledging ambiguity and engaging in open discourse.

Summary: Accurate measurement of antiretroviral adherence is essential for targeting and rigorously evaluating interventions to improve adherence and prevent viral resistance. Across diseases, medication adherence is an individual, complex, and dynamic human behavior that presents unique measurement challenges. Measurement of medication adherence is further complicated by the diversity of available measures, which have different utility in clinical and research settings. Limited understanding of how to optimize existing adherence measures has hindered progress in adherence research in HIV and other diseases. Although self-report is the most widely used adherence measure and the most promising for use in clinical care and resource-limited settings, adherence researchers have yet to develop evidence-based standards for self-reported adherence. In addition, the use of objective measures, such as electronic drug monitoring or pill counts, is limited by poor understanding of the source and magnitude of error biasing these measures. To address these limitations, research is needed to evaluate methods of combining information from different measures. The goals of this review are to describe the state of the science of adherence measurement, to discuss the advantages and disadvantages of common adherence measurement methods, and to recommend directions for improving antiretroviral adherence measurement in research and clinical care.

OBJECTIVE: To identify gender differences in social and behavioral factors associated with antiretroviral adherence. DESIGN: Prospective cohort study. SETT