Determinants of adherence

The variables in adherence are the patient, the clinician, the regimen, the clinical setting, the disease itself, and the amount of sustained support provided to the person on therapy.

There is a greater likelihood of adhering to a regimen if there is trust between the clinician and patient, if it is possible to discuss obstacles and occasional pill-taking lapses in a non-judgemental way, and if there is ongoing support throughout therapy. There are guidelines for when antiretroviral (ARV) therapy is indicated, but a CD4 count or viral load is only the starting point of the decision-making process. After treatment is started, a physician or other member of the healthcare team needs to address and assess adherence regularly. A pharmacist is in a uniquely informed position to evaluate a regimen and assist with the challenges it may bring.

Before starting on therapy, it is critical that patients have an understanding of how HIV disease progresses, how medication works to suppress the virus, the side-effects ARVs can have, and the need to incorporate pill-taking into a daily schedule if and when treatment is decided upon.

In the Dutch cohort ATHENA, self-reported non-adherence was associated with a near doubling in the risk of having a detectable viral load. Non-adherence was most strongly linked to a lack of conviction in the need for therapy. An association between side-effect concerns and adherence was not observed. Patients who were not fully convinced that they needed to follow the regimen requirements were significantly more likely to be non-adherent.¹

During the first few months on treatment, there is generally a reliance on clinical staff for informational and moral support, including discussions of side-effects, coping strategies, and everyday problems in sticking to a regimen. Over time, the need for support continues, but some of the reliance may be transferred to a widened base of family, friends, neighbours, or community-based treatment supporters.

Support for adherence may come from friends and family, a buddy system, peer counselling, or support groups. Each person on therapy needs to identify the form of support they believe will be most helpful to them and perhaps experiment with various options to see what actually works effectively. Because adherence is a constant issue over time, the type of support needed to adhere to a treatment regimen may change over time and will vary with each individual.  

Directly observed therapy (DOT) has been successful in many settings. DOT is often provided through ‘treatment supporters’, who are people from the local community. Many people have succeeded on a regimen through DOT.

Although not on official DOT programmes, other people have done well on treatment when there is someone nearby who checks in with them daily. Some people benefit by having someone to ask whether they’ve taken their pills and who is available to listen to problems. Others, if not feeling well, may need help in the form of someone to help them with meals or to count their pills for them and make sure they are taken on schedule.

Health status will affect the ability to stay on a regimen. If someone is not feeling well or eating a healthy diet, it will be more difficult to stay on treatment. The same may be true of someone who is depressed or has a reliance on street drugs or alcohol. In these circumstances, added support measures need to be identified and implemented. 

Those who live in areas with limited resources must contend with even more obstacles in obtaining and staying on treatment. One recent study looked at challenges to adherence for patients attending public and private clinics in Tanzania, Uganda, and Botswana. Each facility provided HIV treatment without charge to patients. Interviews and focus group discussions with both patients and staff were conducted in order to identify problems in adhering to therapy.²

The study found that patients were highly motivated to take ART as prescribed and adherence levels were high. Barriers to success included the cost to travel from a remote area to a clinic, clinic registration fees, long waiting times, hunger, stigma, side-effects, poor or infrequent counselling, limited numbers of healthcare workers, and the large numbers of patients attending clinic. 

The authors concluded that ART programmes needed to help with transportation and food costs for patients under hardship conditions; that when successful adherence levels were achieved, a three-month supply of medication in place of a one-month supply could be given to reduce the number of clinic visits and/or reduce time away from work; that better information on adverse events was needed; and that pharmacists play a very useful role in follow-up care.