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ANTIRETROVIRAL ADHERENCE IN SOUTH AFRICA:

SOCIETAL FACTORS AND BIOLOGICAL CONSEQUENCES
By

IAN SCOTT METZLER


A THESIS
Presented to the Department of Human Physiology

and the Honors College of the University of Oregon

in partial fulfillment of the requirements

for the degree of

Bachelor of Science


July 2007

An Abstract of the Thesis of

Ian Scott Metzler for the degree of Bachelor of Science

in the Department of Human Physiology to be taken July 2007

Title: ANTIRETROVIRAL ADHERENCE IN SOUTH AFRICA:

SOCIETAL FACTORS AND BIOLOGICAL CONSEQUENCES


Approved: _______________________________________________

Professor Janis Weeks


HIV/AIDS has caused millions of deaths and untold suffering throughout the world. Although there is no cure, treatment exists that has transformed this disease from an acutely lethal infection into a manageable chronic illness. However, successfully treating HIV/AIDS requires high levels of adherence to prescribed medications. Unlike most aspects of antiretroviral treatment, adherence depends on the behavior of the patient, which is influenced by a multitude of factors from every sector of society. This paper discusses the challenges to treatment adherence within a model country, South Africa. To highlight the necessity of addressing obstacles to adherence, this paper also investigates the biological consequences resulting from poor adherence. These consequences are significant for both the individual and humanity as a whole. Establishing a medical strategy to treat HIV/AIDS is not enough; turning the tides of the HIV/AIDS pandemic will require an understanding of the societal factors affecting adherence as well.
TABLE OF CONTENTS

Section Page


I. INTRODUCTION..........................................................................................................1

South Africa as a Model......................................................................................3

Background on HIV/AIDS and Antiretroviral Treatment..............................5

The Biological Players..............................................................................5

Antiretroviral Treatments..........................................................................7

Medication Adherence......................................................................................10

What is Adherence?.................................................................................10

The Adherence Situation in South Africa................................................11

The Challenge of Measuring Adherence.................................................13
II. SOCIETAL FACTORS AFFECTING ANTIRETROVIRAL ADHERENCE..........19

How Does a Patient’s Environment Affect their Ability to Adhere?...........19

Health Service Factors......................................................................................20

Accessibility of ART Facilities.................................................................21

Staffing Limitations.................................................................................23

Medication Supply...................................................................................24

Disability Grants.....................................................................................25

Economic Factors..............................................................................................27

Medication and Care Costs.....................................................................27

Additional Expenses................................................................................28

Balancing Employment with Medical Responsibility..............................30

Social and Cultural Factors..............................................................................32

Treatment Misconceptions.......................................................................32

Disclosure Obstacles...............................................................................34

Benefits of Social Support.......................................................................35

Contradictions in Public Leadership.......................................................36

Cultural Discord in Care.........................................................................38

Disease and Treatment Factors........................................................................42

Asymptomatic Nature of HIV/AIDS .......................................................42

Side Effects..............................................................................................43

Pill Load, Dosing Frequency and Regimen Complexity.........................45

Poor Adherence Resulting from Barriers to Adherence................................46
III. BIOLOGICAL CONSEQUENCES OF POOR ADHERENCE...............................47

Incomplete Suppression of HIV.......................................................................48

Treatment Failure and Disease Progression...................................................49

Increased Probability of Transmission...........................................................51

Development of Drug Resistance.....................................................................53
IV. CONCLUSION.........................................................................................................59
BIBLIOGRAPHY...........................................................................................................62

I. INTRODUCTION
Often referred to as the modern plague, the pandemic caused by the Human Immunodeficiency Virus (HIV) is unlike any other biological threat our species has faced. It is responsible for 2.8 million deaths in a single year and relentless suffering in its 38.6 million present victims (UNAIDS 2006). HIV subversively undermines our immune system, crippling the physiological defenses designed to protect us from this very type of threat. But the terrible effects of HIV take time to manifest into Acquired Immune Deficiency Syndrome (AIDS), allowing an unwary host to further spread infection. There is no vaccine. There is no cure. Once HIV/AIDS takes hold within a population, its grave consequences begin to emerge. The most productive age groups are hardest hit—destabilizing the area’s economy and leaving millions of orphaned children (UNAIDS 2006). Some regions are so adversely affected by the epidemic that the term ‘undeveloping country’ has been coined to describe nations smothered by HIV/AIDS (Berger 2002).

A medical crisis as socially complex and far-reaching as the HIV/AIDS pandemic stirs much controversy about what strategy will best forestall disaster. Epidemiologically, there are two approaches to managing widespread disease—prevention and treatment. Many public health programs have emphasized prevention measures over treatment provision in developing countries primarily because they are less expensive. While prevention is absolutely vital in the fight against HIV/AIDS, especially where resources are limited, this uneven focus may have promoted the appallingly inadequate medical care available to the same populations. International public health authorities Joia Mukherjee and Paul Farmer write,

Prevention of HIV infection is often promoted as the only feasible option in resource poor settings despite the existence of drugs to treat it. As recently as 2002, experts argued that prevention should take priority over treatment for AIDS in Africa based on cost effectiveness. However, cost effectiveness analyses fail to take into account the most important reason for implementing widespread HIV treatment—treating sick people (Mukherjee et al. 2003).
It is essential that in the midst of managing a pandemic, we do not get lost in the incomprehensible numbers and remember that, above all, this terrible virus robs people of their lives. Thanks to the diligent efforts of dedicated scientists, we now have antiretroviral medications to treat HIV/AIDS, granting more years of life to HIV-positive individuals and improving the quality of that time.

Fortunately, access to this critical treatment is expanding throughout the world. The efforts of governments, non-profit organizations and international funding groups have aided countless people by providing the life-prolonging therapies. However, we must also realize that the initiation of HIV/AIDS treatment is exactly that, the beginning. Because HIV/AIDS is a chronic condition, treatment must be maintained for the rest of the patient’s life. This sustained adherence depends on a multitude of factors, many of which fall outside of the patient’s immediate control. From economic pressures to cultural misconceptions, patients are confronted by considerable obstacles that could jeopardize their antiretroviral treatment.

Without the proper compliance to prescribed medications, HIV will ultimately prevail within the non-adherent patient. However, the ramifications of poor adherence are more severe than just poor treatment outcome. These consequences extend beyond the individual, undermining our ability to treat HIV/AIDS and threatening the world as a whole.

If adherence is not effectively addressed in parallel with treatment expansion, then “the provision of antiretroviral drugs will produce chaos, not control” (Horton 2000). This paper explores HIV/AIDS treatment adherence within a model country, South Africa. It will first set the stage by introducing South Africa and explaining this country’s relevance as a model for an analysis of adherence. Secondly, this paper presents the necessary background information about HIV/AIDS, available treatments and adherence. The bulk of this paper addresses the societal factors within South Africa that affect a patient’s ability to adhere to his or her medication regimen. By discussing multiple examples across various sectors of society, this paper aims to illustrate the complexity and diversity of the issues surrounding adherence. Lastly, this paper examines the biological consequences and public health implications of poor adherence in order to highlight the severity of this challenge.


South Africa as a Model

HIV/AIDS has spread across every inhabited continent and infiltrated even the most isolated communities. However, this deleterious dispersion has been far from uniform. Sub-Saharan Africa contains only one tenth of the world’s population, but approximately 64% of the world’s HIV-infected population reside in this region as of 2005 (UNAIDS 2006). Prevalence rates—the percentage of people infected with HIV—in these countries hover between 15-34%. South Africa’s prevalence rate is estimated at 16.2% (WHO 2005). Although this value is on the lower side, South Africa differs from its neighbors with higher rates because the prevalence rate in South Africa is increasing (UNAIDS 2006). Furthermore, an estimated 5.5 million HIV-positive people live within the borders of South Africa—more than any other country in the world (McNeil 2007). Clearly, South Africa sits securely at the apex of the global HIV/AIDS pandemic.

In addition to statistics stressing South Africa’s relevance in any discussion of HIV/AIDS, this country is politically, socially and culturally unique. The current government was installed in 1994 with the dissolution of the racially oppressive apartheid regime. The new administration adopted one of the most liberal constitutions in the world, including rights to free and universal healthcare, but the political system is still immature and has yet to fulfill many of its early promises (Thompson 2000). With the fall of apartheid, racial restrictions were removed and South Africa became the multicultural ‘rainbow nation’. Regretfully, the country is still rife with social inequality even after this transformation. Moreover, despite the country’s relative wealth, there is tremendous economic disparity present in South Africa. Like a jumble of assorted jigsaw puzzles, South Africa is characterized by an array of interspersed ethnic and economic groups. The intersection of first and third worlds under a new democracy, infused with extraordinary cultural diversity, makes South Africa an ideal environment to study the societal factors that affect treatment adherence. Many of the elements associated with HIV/AIDS treatment anywhere in the world are exaggerated in the context of South Africa, be it by the social environment or the sheer numbers of affected people.
Background on HIV/AIDS and Antiretroviral Treatment

The Biological Players

HIV stands for Human Immunodeficiency Virus; reversing this wording helps illustrate its definition—it is a virus that specifically targets and devastates the immune system in humans. As with all viruses, HIV is a particle many times smaller than a cell, which contains genetic material protected by a protein envelope. Once HIV enters the body, it seeks out its target—our immune system. The human immune system is a network of vessels and specialized junctions through which cells called leukocytes (white blood cells) monitor physiological conditions and share information about sites of damage and foreign invasion. These leukocytes come in many forms so they can successfully identify and manage a variety of physiological problems. Most relevantly, HIV seeks out helper T-cells, a certain type of leukocyte that detects foreign antigens and communicates the threat throughout the immune system. HIV infects helper T-cells, among a few other types of cells, because they exhibit surface proteins called CD4-receptors which, under normal circumstances, lets them recognize certain types of pathogens (Weeks and Alcamo 2006) p.72). However, after infection, the CD4-receptor acts as a lock to which HIV has the key, allowing the virus into the cell.

Inside the host cell, HIV’s protective capsule dissolves, releasing the ribonucleic acid (RNA) based genetic material and viral enzymes. Viral reverse transcriptase (RT) transcribes the RNA chain into deoxyribonucleic acid (DNA)—the genetic material found in human cell nuclei. Normal cellular processing transcribes DNA into RNA copies which are then used to construct proteins. So RT’s synthesis of DNA from RNA is backward, earning HIV its classification as a ‘retrovirus’. The new viral DNA strand migrates to the nucleus of the host cell where another viral enzyme, integrase, incorporates it into the host genome. After this stage, HIV is permanently assimilated into the host cell and referred to as a provirus where it can lie dormant for many years. The eventual stimulation of the HIV provirus produces new RNA strands which manufacture viral proteins by hijacking the host cell’s biological machinery and resources. Lastly, a third viral enzyme, protease, cleaves the proteins into active forms. These components congregate at the cell surface and bud off as new HIV particles, continuing to spread the infection.

While the initial phase of the disease manifests itself with symptoms similar to the common cold, the HIV infection steadily grows in strength and severity. Eventually, it incapacitates the majority of CD4-positive T-cells (CD4) which are crucial to the function of the immune system as a whole. Proper diagnosis depends on many factors, but when an individual reaches a CD4 count lower than 200 cells/µL of blood—a significant drop from normal levels of about 1000 cells/µL—they are generally diagnosed with Acquired Immunodeficiency Syndrome (AIDS) (Centers for Disease Control and Prevention 1992). The period from initial infection to AIDS take between 10-12 years on average. Clinically, the progression of HIV/AIDS is monitored by laboratory tests which report the concentration of HIV RNA—called viral load (VL)—and the CD4 count. Aside from opportunistic infections, the direct consequences of AIDS often include chronic diarrhea, wasting syndrome, prolonged fever, dementia and a type of cancer called Karposi’s sarcoma (Weeks and Alcamo 2006) p81).

However, the degradation of the immune system does not usually cause death but instead renders the body incapable of fighting off normally benign pathogens. Opportunistic diseases result from organisms across a broad range, including: protozoa, fungi, bacteria and other viruses, which exploit the body’s shattered defenses. AIDS-related illnesses affect multiple regions of the body such as the pulmonary, gastro-intestinal and neurological systems. The types of opportunistic diseases that are most prevalent in a population depend on the region; for example, tuberculosis has an extremely high incidence rate among HIV-positive individuals in many African countries whereas it is relatively rare in the US. Consideration of these secondary infections is vital in overall treatment, because these opportunistic diseases directly kill individuals with AIDS.
Antiretroviral Treatments

Despite the discouraging outlook of HIV/AIDS progression, hope lies in the fact that viable treatments have been developed over the last two decades to curb the lethal course of this illness. The first antiretroviral drug approved by the FDA in 1987 was AZT (zidovudine), originally designed to treat cancer. This drug was successful in that it slowed disease progression and instilled optimism in the HIV/AIDS-affected community. Regretfully, it was later shown that treatment with AZT did not increase overall survival rate (Institute of Medicine 2005a) p43). This outcome, which will be explained below, spurred drug development in several different directions ultimately producing four distinct classes of drugs.

The first were nucleoside reverse transcriptase inhibitors (NRTI), AZT included, which stop the process of elongation performed by the viral enzyme RT. As mentioned earlier, without functional RT, viral RNA cannot be converted to DNA, stopping HIV in its tracks. To produce DNA, this enzyme strings nucleosides, the building blocks of genetic material, together in a sequence that complements a template strand of RNA. NRTIs work by resembling a nucleoside in every aspect except the portion that couples with the next nucleoside in sequence. If RT incorporates a NRTI into its DNA copy the reaction cannot continue, which leaves the enzyme blocked and the DNA strand unfinished. If RT were a machine that manufactures a long metal chain by connecting the links one at a time, administering a NRTI is essentially throwing scrap metal on the conveyer belt until the machine clogs and breaks down. A second group of medication targets RT with a different approach. Non-nucleoside reverse transcriptase inhibitors (NNRTIs) directly react with the RT enzyme and inhibits it’s activity. In the same analogy, NNRTIs take a sledgehammer to the chain-making-machine—the overall outcome is the same.

Researchers did not stop at RT when developing HIV-enzyme inhibiting drugs; protease was also a target for drug development. Substances that fit into the active site of this enzyme are called protease inhibitors (PI) and prevent new viral proteins from being cleaved into viable forms. This slows the progress of HIV infection because new viruses cannot effectively form and bud off from the host cell without the appropriate proteins. The last class of antiretroviral drugs, fusion inhibitors (FI), halts HIV before it can enter and infect host cells. This drug became available for clinical use in 2003, but is reserved for patients in which the other treatments have failed (Institute of Medicine 2005b). FI works by blocking the interaction between HIV and the CD4-receptors of the host cells. FIs carry promise because they could potentially prevent HIV infection even after system exposure.

Researchers continue to expand on current treatment strategies as well as invent completely novel approaches, yet the most significant advance in alleviating the morbidity and mortality resulting from HIV infection has not been a single drug discovery but the utilization of combination treatment. The use of three or more antiretroviral (ARV) drugs from at least two of the classes is termed highly active antiretroviral treatment (HAART or ART) and is the recommended form of treatment (Institute of Medicine 2005b). With the advent of HAART in 1996, HIV/AIDS has begun to transform into a manageable chronic illness instead of an acutely lethal infection. The effect of this therapy was immediately apparent; the number of AIDS-related deaths decreased by 43% in the US from 1995 to 1997 (Institute of Medicine 2005a). However, as discussed below, this positive outcome of new treatment did not have the same effect reducing the death toll in many developing countries like most of sub-Saharan Africa.
Medication Adherence

What is Adherence?

Despite the many successes, none of the previously mentioned treatments are a cure. Once an individual becomes infected with HIV, they must manage the disease and associated therapy for the rest of their life. Successful ART is defined as “maximal and durable suppression of viral load, restoration and preservation of immunologic function, improvement of quality of life, and reduction of HIV-related morbidity and mortality” (Dybul et al. 2002). This positive outcome is possible with ART, but it requires strict and accurate adherence to the prescribed treatment.

Optimal adherence has been defined based on the virologic, immune, and clinical outcomes of patients whose adherence was measured during longitudinal studies. For PI-based ART regimens, (Paterson et al. 2000) describes optimal outcome in patients who take ≥95% of the medications prescribed by their physician. Specifically, they showed that there was a significant decrease, from 80% to 50%, in virologic success, or reduction of a patient’s VL, with patients who had <95% adherence. Although this sharp drop in positive virologic outcomes was not shown in NNRTI-based regimens, there was still a linear relationship between adherence and virologic outcome (Nachega et al. 2007). This suggests that as the patient’s adherence level to NNRTI-based regimens increases, there is a respective increase toward a positive outcome continuing up to perfect, 100%, adherence. Therefore, the majority of literature defines the cut-off for optimal adherence to either PI- or NNRTI-based regimens between the relatively high levels of ≥90-95%. Because of this important adherence threshold, publications addressing adherence most often report the percentage of patients with optimal adherence instead of just the average adherence rate.

With such a large pill load, maintaining such exceptional levels of adherence requires precise and rigorous treatment management. A South African patient taking the first-line ARV regimen must take five pills in 24 hours. Compared to patient’s that can afford the combination pills that include several drugs within one pill, this is a very high frequency. In order to remain >95% adherent to ART, a patient could miss no more than seven out of the 150 pills the patient takes per month, and they must be taken at the prescribed time. Moreover, like any other substance in the bloodstream, ARVs are metabolized and excreted as time passes. In order to keep blood concentrations of the viral-suppressing drugs at effective levels, it is also imperative that patients take their medications within an hour of the designated time (Bartlett 2005). When patients do not accurately adhere to their regimen schedule and take their drugs too late or too early, blood concentrations can drop below the level necessary to suppress HIV or rise to levels that are hazardous to the patient.


The Adherence Situation in South Africa

On September 3, 2003, headlines of the New York Times read, ‘Africans Outdo US Patients in Following AIDS Therapy’ (McNeil 2003). This optimistic pronouncement came as a response to several African studies on adherence rates, including one from South Africa (Orrell et al. 2003). These quantitative studies reported higher—hovering around 90%—averages of ARV adherence compared to the respective data from the US, which reported average adherence around 70% (McNeil 2003). A more recent journal article analyzed 58 adherence studies across North America and sub-Saharan Africa and reported a similar disparity. (Mills et al. 2006b) determined that an average of 55% of patients in the US and 77% of the patients in Africa achieved optimal adherence levels. These remarkable conclusions are reassuring and rebuff pessimistic sentiments that predicted ‘doomsday’ scenarios for the widespread provision of ART in sub-Saharan Africa (Harries et al. 2001; Popp and Fisher 2002). However, as will be addressed below, many concerns about ART in Africa and potential negative consequences are worthy of serious discussion.



Several studies specific to South Africa also showed relatively high percentages of patients with optimal adherence (Table 1). For all these region-specific studies the average percentage of patients with optimal adherence was 70%, similar to that reported for all of sub-Saharan Africa (Mills et al. 2006b).
Table 1 – Adherence Reports in South Africa

Source

Location

No. of Participants

Method of Assessment

Duration of Study

Percentage of Patients with Optimal Adherence*

(Brown and Friedland 2004)

Durban

50

Self-Report

12wks

76% had ≥100% adherence

(Darder et al. 2004)

Cape Town

192

Self-Report

12mos

88% had ≥95% adherence

(Ferris et al. 2004)

Durban

74

Self-Report

N/A

77% had ≥95% adherence

(Nachega et al. 2004)

Soweto

66

Self-Report

1mo

88% had ≥95% adherence

(Nachega et al. 2006a)

Cape Town

6288

Pharmacy claims

12mos

30% had ≥100% adherence

(Nachega et al. 2007)

Cape Town

2821

Pharmacy claims

2.2yrs

47% had ≥90% adherence

(Orrell et al. 2003)

Cape Town

289

Pill counts and pharmacy refill

48wks

45% had ≥95% adherence

*as defined by individual study

While they show relatively high levels of adherence, none of the studies argue that adherence is not a vital aspect to successful ART and they acknowledge adherence as a complex and socially-intertwined variable. Mills et al. (2006a) and the authors of almost every included study reiterate, and aim to demonstrate with their data, that prejudice-rooted reservations about ARV adherence in Africa are simply not valid based on the data (Mills et al. 2006a; Nachega et al. 2004; Orrell et al. 2003). They argue that concerns about adherence should in no way discourage the provision of ART in sub-Saharan Africa, the region hardest by the HIV/AIDS pandemic.

While this paper agrees with the conclusions of the aforementioned authors and highly value their contention regarding access to ART in sub-Saharan Africa, it must draw attention to the many limitations of adherence studies in order to promote a healthy skepticism when interpreting such impressive headlines as those reported in the New York Times. Moreover, the following analysis strives to expose and challenge a possible unintended consequence of the previously mentioned studies—a false sense of security about the adherence situation in South Africa that could potentially cause a decline in the awareness, funding, and vigilance required for success in the battle against HIV/AIDS.
The Challenge of Measuring Adherence

The high degrees of adherence necessary for successful ART allude to the importance of accurately and precisely assessing this variable. However, an array of methods for measuring adherence exist (Table 2). Each contains distinct advantages and disadvantages including cost, complexity, accuracy, intrusiveness and bias. There is no gold standard, and the selection of a particular method varies depending on availability and researcher preference. By analyzing studies measuring adherence, (Gill et al. 2005) found large discrepancies between the different methods used on the same groups. With this information they constructed a relative hierarchy of adherence measurement methods, “with physician assessment and self-report being least accurate, pill counts intermediate, and EDM [electronic drug monitoring] the most accurate surrogate adherence marker”. The ideal way to measure adherence would be through a program modeled after the tuberculosis control strategy, direct observed treatment short-course (DOTS) which requires a treatment supporter to oversee compliance to the medication regimen for every dose. DOTS has proved extremely effective at controlling tuberculosis in resource-constrained settings but has yet to be successfully implemented for ART (Liechty and Bangsberg 2003). This hierarchy provides a qualitative comparison between measures useful for discussing the strengths and weaknesses of any adherence study.



So far, all of the adherence studies conducted in South Africa have employed the less reliable methods of self-report or pharmacy claims as seen in Table 1. The majority of the selected reports, including those cited by the New York Times article and other broad reviews of ARV adherence patterns, utilize the self-report technique. As with any subjective measurement dependent on patient recall, concerns with the inherent bias of self-reporting are significant.

Information about clinical outcomes of patients participating in adherence evaluations provides evidence supporting this reservation about the self-reporting method. The link between high levels of adherence and undetectable viral loads (UDVL) has been established in multiple studies using EDM and DOTS (Chesney et al. 1999; Gill et al. 2005; Paterson et al. 2000). These studies found UDVL in 78%-85% of their patients with optimal adherence. In comparison, the data reported by (Brown and Friedland 2004), who used self-report to assess adherence, showed that only 57% of the group claiming 100% adherence achieved UDVL. Although this negative outcome did not occur in all self-report studies, it illustrates a potential disconnect between self-report and virologic outcome.

Furthermore, a comparison of the two groups in Table 1, those studies using self-report and those using the more objective pharmacy claims, displays a remarkable pattern. The self-report studies all present data that places adherence at a very high level, with an average 82% of the patients achieving optimal adherence as defined by the individual study. However, a dramatically lower percentage is reported by the studies using pharmacy claims. For these two studies, the average percentage of patients achieving optimal adherence drops to an alarming 40.8%, half the value determined by self-report. According to these pharmacy claim studies, less than half of the participants are taking their treatment at the level required for ideal treatment outcomes. This sharp drop between studies, similar in most respects except their assessment methods, supports the notion that bias in self-reporting has a considerable false-positive effect on the adherence studies.

The participant population for adherence studies in resource-constrained settings elicits separate concerns. First, in a country where ART is restricted to a narrow minority, the individuals who first gain access may “possess greater resources, heightened motivation, and are probably not representative of the larger HIV epidemic” (Bangsberg, Ware and Simoni 2006). In addition to population bias, there is considerable selection bias in these studies. Often, the participants were referred to the studies from a hospital specifically because their motivation regarding ART was above average (Orrell et al. 2003). Furthermore, strict inclusion rules for participants may have selected for patients with a social situation facilitating high adherence. The Darder et al. (2004) study had substantial inclusion guidelines, as reported by the same New York Times article,

To qualify for treatment, patients must give up all alcohol and drugs; complete three months of taking a simple antibiotic; be on time for four clinic appointments in a row; reveal to their families that they are H.I.V. positive; and choose a friend who must come to counseling, make sure all pills are taken and report problems to a nurse (McNeil 2003).


Clearly, these stringent guidelines would exclude patients with social conditions and mentalities that predispose them have poor adherence. Even more blatantly, Orrell et al. (2003) excluded the data of 47 (16%) patients who discontinued ART before the completion of the follow-up. The unrepresentative character of the available populations as well as inclusion and exclusion biases of these studies greatly limit the applicability of their conclusions to the larger population—especially the disadvantaged, and often ignored, populations whose adherence is of greatest concern.

Lastly, the environment created by the researchers may also skew the results toward better adherence. In all of the publications that reported this information, the large majority of participants received ARVs free of charge directly from the study or through some other organization, thus removing any drug-cost-related barrier to adherence. In several of the listed studies, patients received information and support from dedicated staff, a beneficial environment which is not representative of the widespread healthcare experience in South Africa. This extra education and attention doubtlessly promoted adherence and again reduces the applicability of these findings to the larger population. Essentially, these studies removed many of the barriers to the very thing they were attempting to quantify.

The publication by Orrell et al. (2003) that provoked the New York Times article proclaiming that Africans had trumped their North American counterparts is titled, Adherence is not a barrier to successful antiretroviral therapy in South Africa. More explicitly, Orrell et al. (2003) and the other research groups have shown that adherence does not have to be a barrier when adequate access to ART is provided, education and support is available, and adverse social conditions are addressed. The conclusions of the selected researchers are positive, and they inspire optimism that success is possible for long term ART as it becomes available in South Africa. However, the environment in which these studies were conducted is not representative of that experienced by the vast majority of people in South Africa in need of ART.

Furthermore, the majority of the available studies focused on the magnitude and the qualities of non-adherent populations not the causes of the aberrant behavior. Also noticing this trend, (Gill et al. 2005) writes, “Unfortunately, while epidemiological studies are helpful at identifying ‘Who is non-adherent?’ they provide less insight into the more pressing question of ‘Why?’”. The following section will address the reality of life for HIV-positive South Africans in an attempt to answer ‘Why?’ and to promote understanding of the complexity and diversity of challenges to ART adherence.



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