Introduction
Clinicians should consider substance users candidates for highly active antiretroviral therapy (HAART) if they meet the medical eligibility criteria for HAART and demonstrate readiness to begin therapy by attending the majority of their appointments and expressing interest in antiretroviral therapy (ARV) treatment.
Key Point:
History of substance use or current substance use should not be the sole factor in withholding HAART from eligible patients. Decisions about when to prescribe HAART for eligible drug-using patients should be made on a case-by-case basis.
Predictors of Adherence
Key Point:
A strong patient-provider relationship, including trust and engagement with the provider, has been associated with improved ARV adherence.
Addressing Potential Barriers to Adherence before Initiating HAART
Clinicians should identify and address potential barriers to adherence before initiating HAART in human immunodeficiency virus (HIV)-infected substance users (see the Table 1 below). If clinicians elect to defer prescribing HAART while addressing potentially modifiable barriers to adherence, they should discuss this decision with the patient.
Clinicians should reassess potential barriers to adherence at least every 3 to 4 months and whenever adherence problems are identified.
Clinicians should discuss with patients the known interactions between prescribed medications and illicit substances.
Table 1
Potential Barriers to Adherence |
- Active substance use
- Inadequate substance abuse treatment
- Lack of social stability (e.g., housing problems, legal issues) or social support (e.g., disrupted family and community ties, unstable relationships)
- Lack of belief in medications or denial about being HIV-infected
- Poor self-efficacy
- Regimen does not "fit" with patient's daily routine
- Untreated mental illness, particularly depression
- Side effects
- Drug-drug interactions
|
Additional Barriers to Address with Patients Receiving Concurrent Opioid Pharmacotherapy
Clinicians should educate patients who receive concurrent opioid pharmacotherapy and ARV therapy about the safety and efficacy of methadone and buprenorphine because these patients may have misconceptions regarding the safety of concurrent opioid pharmacotherapy and ARV therapy.
Clinicians should assess potential interactions between HAART and methadone before and during therapy by inquiring about oversedation and opioid withdrawal symptoms. If withdrawal symptoms are present, the primary care clinician should conduct a detailed history and facilitate a dose increase by educating the patient and communicating with the methadone provider.
Adherence and Antiretroviral Resistance
Clinicians should counsel patients before initiating ARV therapy and at routine monitoring visits during therapy concerning the need for strict adherence and the risk of viral drug resistance when adherence is compromised.
Clinicians should perform a thorough adherence assessment and obtain antiretroviral resistance assays prior to changing regimens in patients who are receiving a failing regimen (failure to demonstrate >1.5-log drop in viral load within 3 months of initiating treatment and, more importantly, failure to achieve a viral load <50 copies/mL within 6 months of initiating treatment).
Measurement of Adherence
Clinicians should assess adherence at every routine monitoring visit.
Clinicians should use finite time intervals when inquiring about and quantifying the patient's self-report. Clinicians should average responses across visits to obtain a more accurate estimate of adherence.
When assessing adherence, clinicians should use precise language that the patient can understand. In addition, clinicians should verify that patients are taking the medications as prescribed, specifically, correct medications, correct number of pills per dose, and correct number of doses per day.
Key Points:
- Adherence measurements averaged from repeated adherence assessments will yield a more accurate calculation of adherence than one-time assessments.
- Clinicians' estimates of patient adherence have been shown to be inaccurate and should not be substituted for a thorough adherence assessment.
Interventions to Improve Adherence
Clinicians should refer patients to substance use treatment programs to optimize patients' ability to successfully utilize and adhere to HAART and other medical therapies (Samet, Friedmann, & Saitz, 2001; Sorenson et al., 1998).
Adherence intervention strategies should include the following elements:
- Education and motivation, including treatment readiness, should be part of every visit
- If medically feasible, simplifying the regimen and tailoring it to the patient's lifestyle
- Preparation for and management of side effects
- Identification and treatment of depression and other psychiatric conditions
- Substance use treatment
- Involving an adherence team or monitor
- Referring the patient to social services and mental health providers for assistance in dealing with (or resolving) issues that are barriers to adherence
Clinicians and substance-using patients should work together to develop a plan to decrease or stabilize substance use in preparation for initiating ARV therapy.
Key Point:
Behavioral skills and motivation are crucial factors for promoting behavior change.
Table 2
Interventions to Improve Adherence |
| Determinant |
Action to improve Adherence |
Beliefs and knowledge (of HIV medications)
Self-efficacy and adherence
Memory (difficulty remembering doses)
|
Educate patient; provide information
Enhance motivation
Offer patient visual aids to help remember daily regimen; use beepers, pillboxes, and other reminders |
