Adam Kaplin, M.D. and Jeffrey Hsu, M.D.
- Adherence recommendations from Zambian guidelines (with author comments in parentheses):
- -Drugs should be taken at same time of day to maintain steady drug blood levels, at correct doses, with or without food (if indicated), and without skipping doses or interrupting therapy. (Importance of dose timing depends on PK of individual drugs.)
- -NNRTIs have low genetic barrier to resistance; adherence is essential to prevent development of resistance and ultimately treatment failure. (Long half-lives may prevent resistance with delayed or missed doses, but high risk of resistance with treatment interruption.)
- -Give written dosing instructions to patients.
- -Provide one-on-one counseling to each patient. May require several counseling sessions before patient ready to start ART.
- -Counseling should include information about side effects, including symptoms of serious toxicity, when to seek medical attention, and how to prevent or manage mild side effects.
- -Encourage patients to identify treatment supporters (family members, friends, other people living with HIV) and include them in counselling.
- -Find ways to help patients overcome obstacles, such as disclosure.
- -Link patients with adherence support groups.
- -Counsel patients to avoid drug abuse and to refrain from excessive alcohol use.
- -Given information about how and when to contact health care provider.
- -Assess adherence at every visit using open ended, targeted questions and other tools (e.g. pill counts, pharmacy-based assessments such as medication possession ratio--see below).
- -Assess adherence at every contact with adherence support worker or home-based care giver.
- -Refer patients with suspected or identified adherence problems to ART care team immediately.
- -Patients may be unlikely to volunteer information about non-adherence.
- -To assess adherence, ask how patient is taking prescribed medications. Probe, verify, ask follow-up questions, and assess barriers to adherence. Consider pill counts.
- In one Zambian study, disclosure of HIV status to one's spouse, knowing spouses' HIV status, and having a clinic buddy were associated with good adherence.
- Medication possession ratio (MPR, 100%-(# days late for pharmacy refills/total days on therapy), which is percentage of days patient is known to have medication on hand, has been shown to be predictive of clinical and immunologic outcomes in Zambia.
- Use of adherence support workers has been successfully in Zambia to shift adherence counseling tasks.
- A novel food supplementation pilot study in Zambia showed that it may improve adherence to ART among food-insecure adults.
- Targed adherence interventions in patients with virologic failure can result in subsequent virologic suppression in some patients without need to switch to 2nd-line ART.
Zambia Information Author: Larry William Chang, MD, MPH
- Extent to which pt follows prescribed health care regimen.
- <95% adherence associated w/ increased risk of virologic failure in early studies of unboosted PI-based regimens. May not apply to NNRTI- or boosted PI-based regimens.
- Adherence strongly correlated with viral suppression.
- Adherence results in better CD4 response to therapy.
- Non-adherence associated with resistance. In some studies, risk of resistance highest with good but incomplete adherence (e.g. 80-90%). Little selective pressure with very poor adherence. Link between adherence and resistance also depends on potency/pharmacokinetics of regimen.
- Nonadherence limits future treatment options if it results in resistance.
- Nonadherence increases risk of HIV transmission.
- Behavioral intervention strategies addressing adherence are successful; approach should be tailored to address individual pt needs.
- Complexity of medication regimen (pill burden, food restrictions, dosing frequency)
- Active substance or alcohol abuse
- Untreated psychiatric disorders (e.g., depression, anxiety, personality disorders)
- Side effects
- Poor patient-provider relationship
- Busy, chaotic lifestyle
- Patient lack of knowledge about HIV and rationale for therapy
- Cognitive problems (esp. poor executive functioning, memory, attention, psychomotor speed)
- Lack of social support and concerns about social stigma.
- Most studies show no relationship with race, sex, age, socioeconomic status, or educational level
- Determine pt readiness to begin HAART by assessing beliefs about therapy, social support, use of drugs or alcohol, mental health issues, daily routine, and ability to meet basic needs.
- Identify possible barriers to adherence prior to beginning treatment and identify ways to remove them (transportation to clinic, child care issues, need for stable housing).
- Refer pt for substance abuse/mental health treatment prior to beginning HAART (active substance use, depression, and anxiety disorders are strong predictors of nonadherence).
- Consider using techniques such as motivational interviewing (MI) to improve pt. readiness to begin treatment.
- Establish trusting clinician-pt alliance and invite pt collaboration in treatment decisions.
- Educate pt about treatment regimen, anticipated side effects, importance of adherence, and risk of resistance.
- Appropriately manage medication side effects as they emerge.
- Use written materials and audiovisual aides to help reinforce knowledge.
- If HAART not urgent, consider "trial run" using vitamins or prophylactic medications prior to beginning HAART to assess patient's ability to adhere to medication regimen.
- Schedule regular visits to monitor adherence.
- Questions about adherence should be asked in an open-ended, non-threatening manner.
- Provide available contacts between visits for questions/problems with side effects.
- Provide social support by enlisting help of family members, friends, peer counselors, pt role models, and members of the health care team to reinforce/monitor adherence.
- Simplify regimen as much as possible (high pill burden, food restrictions and increased dosing frequency correlated with lower adherence).
- Choose tolerable medications and be prepared to change drugs if needed.
- Monitor pt adherence with different measures (see below).
- Keep medication diary.
- Establish set time and place for taking medication.
- Identify medication taking cues linked to daily routine (e.g. prior to brushing teeth, eating a meal).
- Use of cell phones, pagers and alarms as reminders
- Use of pillboxes
- Plan ahead for changes in routine (vacations, holidays).
- Notify provider of side effects that may interfere with adherence or if considering discontinuation of therapy.
- Anticipate need for medication refills in advance.
- Pt self-report assessed through questionnaires, interviews, diaries, pills identification test (PIT)
- Pill counts
- Prescription refill monitoring
- Use of electronic devices that measure pt adherence (e.g., MEMS cap )
- Directly observed therapy (DOT)
- Therapeutic drug monitoring (not routinely recommended, but may be helpful in selected cases)
- Viral load/CD4 count (crude and late measures)