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. Author manuscript; available in PMC: 2020 Jun 26.
Published in final edited form as: AIDS Care. 2018 Feb 21;30(7):863–870. doi: 10.1080/09540121.2017.1417527

Social and behavioral factors associated with failing second-line ART – results from a cohort study at the Themba Lethu Clinic, Johannesburg, South Africa

Denise Evans a, Sara Dahlberg b, Rebecca Berhanu c, Tembeka Sineke a, Caroline Govathson a, Ingrid Jonker c, Elisabet Lönnermark b, Matthew P Fox d,e
PMCID: PMC7317067  NIHMSID: NIHMS1585508  PMID: 29463102

Abstract

Poor adherence is a main challenge to successful second-line ART in South Africa. Studies have shown that patients can re-suppress their viral load following intensive adherence counselling. We identify factors associated with failure to re-suppress on second-line ART.

The study was a retrospective cohort study which included HIV-positive adults who experienced an elevated viral load ≥400 copies/ml on second-line ART between January 2013–July 2014, had completed an adherence counselling questionnaire and had a repeat viral load result recorded within 6 months of intensive adherence counselling. Log-binomial regression was used to evaluate the association between patient characteristics and social, behavioral or occupational factors and failure to suppress viral load (≥400 copies/ml).

A total of 128 patients were included in the analysis, and of these 39% (n = 50) failed to re-suppress their viral load. Compared to those who suppressed, far more patients who failed to suppress reported living with family (44.2% vs. 23.7%), missing a dose in the past week (53.3% vs. 30.0%), using traditional/herbal medications (63.2% vs. 34.3%) or had symptoms suggestive of depression (57.7% vs. 34.3%).

These patient-related factors could be targeted for interventions to reduce the risk for treatment failure and prevent switching to expensive third-line ART.

Keywords: second-line antiretroviral therapy, resource limited setting, virologic failure, viral suppression, intensive adherence counselling

Introduction

In South Africa, an estimated 10% of patients started on antiretroviral therapy (ART) will switch to second-line ART, and a further 33–40% of patients are expected to fail treatment in the first 12 months of second-line ART (Fox, Brennan, Maskew, MacPhail, & Sanne, 2010; Onoya et al., 2016). This is similar to the high rates (21–38%) of second-line treatment failure described for other low- and middle-income countries (Ajose, Mookerjee, Mills, Boulle, & Ford, 2012). Poor adherence rather than drug resistance is the main driver for virologic failure on protease-inhibitor (PI)-based second-line (Ajose et al., 2012; Court et al., 2014) and reports show that two-thirds of patients can re-suppress following intensive adherence counselling (IAC) (Cox, 2015; Evans et al., 2016; Fox et al., 2016). With rapid expansion of the ART program in South Africa, understanding factors that contribute to second-line treatment failure is essential to the future success of the national treatment program and highlights the importance of improving adherence on second-line ART. A better understanding of the reasons for failure to re-suppress can lead to the design of targeted interventions that reduce the risk of treatment failure among these patients, and ultimately prevent switching to more expensive third-line regimens. This study aims to aims to identify factors associated with failure to suppress viral load (≥400 copies/ml) among a cohort of patients with an elevated viral load on second-line ART.

Methods

Study site

Themba Lethu Clinic (TLC) is a large, urban public-sector clinic located in Johannesburg, South Africa. Since the start of the national ART program in April 2004, more than 30,000 adults have been part of the TLC cohort, of whom more than 28,000 have started on first-line and over 3000 on second-line ART. The cohort has been described elsewhere (Fox et al., 2013, 2016). TLC follows the South African National Department of Health adult ART treatment guidelines which call for second-line treatment with the boosted protease inhibitor, lopinavir/ritonavir (Department of Health, 2013)

Study design and population

This was a retrospective cohort study. After July 2012 TLC introduced IAC as part of a standardized, targeted approach for all patients with an elevated viral load (≥400 copies/ml) on second-line ART. The IAC intervention for patients failing second-line has been described elsewhere (Fox et al., 2016). Briefly, patients are identified from the electronic medical record called TherapyEdge-HIV™ and are flagged by clinic staff for IAC at their upcoming clinic visit in 1–2 months. At this visit patients bypass the normal clinic queue and undergo detailed IAC with an experienced counsellor or social worker who completes a standardized questionnaire. The questionnaire consists of several open- and closed-ended questions relating to adherence and side-effects, social situation, behavioral characteristics, occupational situation and depression-related symptoms. All patients also complete a standardized adherence screen. The form was developed in the clinic and therefore has not been validated but does allow the provider to assess potential barriers to adherence (Fox et al., 2016).

After counselling patients meet with a senior clinician to discuss adherence and possible side-effects. Patients return in 2–4 months for a repeat viral load test. Patients who suppress their viral load <400 copies/ml continue with second-line treatment, those who do not undergo genotype resistance testing.

Inclusion criteria

All HIV-positive adults (≥18 years) with an elevated viral load ≥400 copies/ml on second-line ART at TLC between January 2013–July 2014 were included. The analysis was restricted to patients who underwent IAC and for whom an adherence counselling questionnaire could be located in their medical file and those with a repeat viral load within six months of intensive adherence counselling.

Data collection

For each patient, data from the adherence counselling questionnaire was linked to the patient’s electronic medical record (TherapyEdge-HIV™) and patient-level data including information on demographics, medications, laboratory test results and other clinical information were extracted. In our study, any symptom suggestive of depression was defined as reporting at least one of the following; feeling sad or anxious, crying frequently, feeling hopeless, having difficulty sleeping or using alcohol to feel better.

Statistical analysis

Our primary outcome of interest was failure to suppress viral load; defined as a repeat viral load ≥400 copies/ml within 6 months of IAC. Numerous studies have used a cut-off of <400 copies/ml to define viral suppression (Johnston et al., 2014; Levison, Losina, Lu, Freedberg, & Wood, 2011). We identified factors associated with failure to suppress using log-binomial regression to estimate relative risks (RR) with corresponding 95% confidence intervals. Factors identified in univariate models (p < 0.2) and variables a priori considered important (i.e., age and gender) were included in the multivariate model. All analyses were conducted using SAS version 9.3 (SAS Institute, Cary, North Carolina, USA).

Ethical considerations

The study protocol was reviewed by University of the Witwatersrand Human Research Ethics Committee (M141187), who approved the use of routine clinical data without informed consent. All patient records and information was anonymized and de-identified prior to analysis.

Results

For the study period, 298 patients had a single viral load ≥400 copies/ml on second-line ART. Of those, 154 (51.7%) patients had an adherence counselling questionnaire and could be linked to clinical data. Of the 154 patients, 128 (83.1%) had a repeat viral load, of which 61% (78/128) suppressed their viral load after IAC (Figure 1). More patients who failed to suppress had a viral load more than 100,000 copies/ml at their first elevated viral load on second-line ART (20% vs. 2.6%) (Table 1).

Figure 1.

Figure 1.

Study enrollment and study outcomes.

Table 1.

Demographic and clinical characteristics of patients with an elevated viral load on second-line ART at Themba Lethu Clinic, stratified by the repeat viral load after intensified adherence counselling (n = 154).

Suppressed (N = 78) Not suppressed (N = 50) No repeat VL (N = 26) P value
Gender, Male, n % 35 (44.9%) 28 (56.0%) 10 (38.5%) 0.317
Age at first elevated viral load, years
  Median, IQR 42.9 (37.7–49.2) 38.7 (33.6–45.0) 41.7 (36.6–47.0) 0.826
   <45 48/76 (63.2%) 39/50 (78.0%) 21/26 (80.8%) 0.230
   ≥45 28/76 (36.8%) 11/50 (22.0%) 5/26 (19.2%)
CD4 count at first elevated viral load
  Median, IQR& 454 (274–593) 266 (201–472) 351 (195–501) 0.784
   <250 cells/mm3 13/60 (21.7%) 21/47 (44.7%) 4/15 (26.7%) 0.703
   250–500 cells/mm3 20/60 (33.3%) 18/47 (38.3%) 7/15 (46.6%)
   ≥500 cells/mm3 27/60 (45.0%) 8/47 (17.0%) 4/15 (26.7%)
Viral load at first elevated viral load
  Median, IQR 2780 (1721–10,442) 4539 (1994–74,153) 12,606 (1684–47,924) 0.269
   1000–10,000 copies/ml 57/77 (74.0%) 29/50 (58.0%) 15/25 (60.0%) 0.620
   10,000–100,000 copies/ml 18/77 (23.4%) 11/50 (22.0%) 8/25 (32.0%)
   ≥100,000 copies/ml 2/77 (2.6%) 10/50 (20.0%) 2/25 (8.0%)
Transfer-in from another facility on second-line ART 9/78 (11.5%) 8/50 (16.0%) 3/26 (11.5%) 0.809
Second-line ART NRTI back-bone
  Abacavir 3/76 (4.0%) 3/49 (6.1%) 0.183
  Zidovudine 29/76 (38.1%) 21/49 (42.9%) 14/24 (58.3%)
  Tenofovir 37/76 (48.7%) 25/49 (51.0%) 8/24 (33.4%)
  Stavudine 7/76 (9.2%) - 2/24 (8.3%)
Time on second-line ART prior to elevated viral load, months (IQR) 21.3 (9.4–35.0) 17.5 (7.8–25.7) 18.1 (10.1–26.2) 0.242
Time to repeat viral load, months (IQR) 4.6 (3.6–5.5) 4.6 (3.7–6.5) N/A N/A
Final treatment outcome**
  Alive and in care 69 (88.5%) 42 (84.0%) 19 (73.1%) 0.020
  Dead 0 (0.0%) 1 (2.0%) 0 (0.0%)
  Lost to follow-up 1 (1.2%) 3 (6.0%) 6 (23.1%)
  Transfer 8 (10.3%) 4 (8.0%) 1 (3.8%)

NRTI; Nucleoside Reverse Transcriptase Inhibitor. IQR; inter quartile range.

Those without a repeat VL (n = 26) compared to those with a VL (n = 128) using Chi square test for proportions or as otherwise indicated using the Kruskal-Wallis test for non-normally distributed continuous data ().

**

Final treatment outcomes defined at the end of follow-up. These included alive and in care, dead (verified through linkage with the National Vital Registration System for patients with a valid South African national identification document (Fox, Ive, Long, Maskew, & Sanne, 2010; Shearer et al., 2014), lost to follow-up (defined as being ≥3 months late for the last scheduled visit with no subsequent visit) and transferred to another facility.

&

CD4 at first elevated viral load on second-line, extracted from the patient medical record and defined as the closest result, up to 180 days prior to but not more than 30 days after, the date the patient received the adherence intervention.

Bolded values are statistically significant at p value < 0.05.

In terms of missing data, characteristics were similar between those included in the analysis (n = 128) and those not included (n = 26; p < 0.05). Compared to those with a repeat viral load, patients without a repeat viral load were more likely to be lost from care (≥3 months late for the last scheduled visit; RR 7.38 95%CI 2.24–24.34), and explains the missing laboratory results (Table 1).

From univariate analyses, we identified factors associated with failure to suppress viral load after intensified adherence counselling (Table 2). These included reporting a missed dose in the past week (RR 1.78 95%CI 1.15–2.74) and using traditional/herbal medications (RR 1.84 95%CI 1.20–2.84). Living with family vs. separated from them (RR 1.87 95%CI 1.01–3.46) was the only social factor associated with failure to suppress. Any symptom suggestive of depression was associated with failure to suppress viral load (RR 1.68 95%CI 1.10–2.57). On their own, only feeling sad or anxious (RR 1.53 95%CI 1.10–2.34) and feeling hopeless (RR 1.73 95%CI 1.12–2.67) were associated with failure to suppress.

Table 2.

Factors associated with failure to suppress viral load after intensified adherence counselling at Themba Lethu Clinic, Johannesburg.

Failure to suppress viral load (n = 50)

Characteristic Proportion not suppressed/N (%) Crude Hazard Ratio (95% CI) Adjusted Hazard Ratio (95% CI)
Education
 Below tertiary 6/12 (50.0%) 1.0
 Tertiary and above 40/108 (37.0%) 0.74 (0.40–1.37)
Employed
 Yes 30/82 (36.6%) 1.0
 No 17/42 (40.5%) 1.11 (0.70–1.76)
Gender
 Female 22/65 (33.9%) 1.0 1.0
 Male 28/63 (44.4%) 1.31 (0.85–2.03) 1.08 (0.86–1.33)
Age
 <45 years 39/89 (43.8%) 1.0 1.0
 ≥45 years 11/39 (28.2%) 0.64 (0.37–1.12) 0.86 (0.70–1.07)
CD4
 <250 cells/mm3 21/34 (61.8%) 1.0
 250–500 cells/mm3 18/38 (47.4%) 1.09 (0.69–1.70)
 ≥500 cells/mm3 8/35 (22.9%) 0.52 (0.27–1.03)
Viral load at first elevated VL
 1000–10,000 29/86 (33.7%) 1.14 (0.66–1.98) 1.01 (0.83–1.23)
 10,000–100,000 11/29 (37.9%) 1.0 1.0
 ≥100,000 copies/ml 10/12 (83.3%) 2.50 (1.69–3.69) 1.21 (0.80–1.82)
Second-line NRTI backbone
 d4T/AZT/ABC 24/63 (38.0%) 1.0
 TDF 25/62 (40.3%) 1.06 (0.69–1.64)
Time on second-line ART
 <24 months 4/9 (44.4%) 1.22 (0.54–2.74)
 24–48 months 11/35 (31.4%) 1.0
 ≥48 months 27/67 (40.3%) 1.10 (0.70–1.75)
Year initiated second-line
 ≤2010 8/31 (25.8%) 1.0
 >2010 34/80 (42.5%) 1.65 (0.86–3.15)
Knows names of ARV’s
 Yes 20/58 (34.5%) 1.0
 No 28/67 (41.8%) 1.21 (0.77–1.91)
Regimen taken as prescribed
 Yes 37/97 (38.1%) 1.0
 No 9/26 (34.6%) 0.91 (0.51–1.63)
Missed pills in last week
 No 24/80 (30.0%) 1.0 1.0
 Yes 24/45 (53.3%) 1.78 (1.15–2.74) 1.10 (0.91–1.34)
Patient has interrupted ARV’s
 No 26/69 (37.7%) 1.0
 Yes 23/57 (40.4%) 1.10 (0.69–1.66)
ARV side effects reported
 No 27/79 (34.2%) 1.0
 Yes 21/46 (45.7%) 1.34 (0.86–2.07)
Takes other chronic medication
 No 32/85 (37.7%) 1.0
 Yes 16/40 (40.0%) 1.06 (0.67–1.70)
Ever had TB treatment
 No 21/65 (32.3%) 1.0
 Yes 28/60 (46.7%) 1.44 (0.93–2.25)
Currently taking anti-TB drugs
 No 47/121 (38.8%) 1.0
 Yes 1/3 (33.3%) 0.86 (0.17–4.32)
Uses traditional/herbal medicine
 No 37/108 (34.3%) 1.0 1.0
 Yes 12/19 (63.2%) 1.84 (1.20–2.84) 1.20 (0.90–1.59)
Use of alcohol
 No 35/99 (35.4%) 1.0
 Yes 14/26 (54.9%) 1.52 (0.98–2.38)
Use of drugs
 No 45/116 (38.8%) 1.0
 Yes 4/10 (40.0%) 1.03 (0.47–2.28)
Financial support
 Employed 30/82 (36.6%) 1.0
 Social grants 3/7 (42.9%) 1.14 (0.46–2.81)
 Family 14/35 (40.0%) 1.07 (0.65–1.75)
 Other 3/6 (50.0%) 1.33 (0.57–3.12)
Use tools to remember
 Yes 44/114 (38.6%) 1.0
 No 4/10 (40.0%) 1.04 (0.47–2.29)
Difficulty reading or understanding instructions
 No 41/109 (37.6%) 1.0
 Yes 5/14 (35.7%) 0.95 (0.45–2.00)
Married
 Yes 40/99 (40.4%) 1.0
 No 10/29 (34.5%) 0.85 (0.49–1.49)
Partners
 Single 13/34 (38.2%) 1.0
 Multiple 32/87 (36.8%) 0.96 (0.58–1.60)
Partner tested HIV
 Yes 26/70 (37.1%) 1.0
 No 2/13 (15.4%) 0.41 (0.11–1.54)
Partner status
 HIV positive 21/53 (39.6%) 0.94 (0.60–1.48)
 HIV negative 2/11 (18.2%) 1.0
 Unknown 5/18 (27.8%) 0.66 (0.30–1.48)
Use of condoms
 Yes 26/63 (41.3%) 1.0
 No 9/31 (29.0%) 0.70 (0.38–1.31)
Desire for children
 Yes 16/42 (38.1%) 1.0
 No 21/67 (31.3%) 0.82 (0.49–1.39)
Feel about clinic staff
 Bad 3/7 (42.9%) 0.94 (0.38–2.32)
 Good 18/41 (43.9%) 1.0
 Neutral 25/73 (34.3%) 0.75 (0.48–1.16)
Disclosed to employer
 Yes 6/22 (27.3%) 1.0
 No 22/49 (44.9%) 1.65 (0.78–3.48)
Difficulty getting time off for medical visits
 No 29/82 (35.4%) 1.0
 Yes 2/6 (33.3%) 0.94 (0.29–3.03)
Frequently travels for work
 No 20/59 (33.9%) 1.0
 Yes 10/21 (47.6%) 1.40 (0.79–2.49)
Afford transport costs to clinic
 Yes 42/113 (37.2%) 1.0
 No 1/4 (25.0%) 0.67 (0.12–3.73)
Lives with family
 No 9/38 (23.7%) 1.0 1.0
 Yes 38/86 (44.2%) 1.87 (1.01–3.46) 1.09 (0.88–1.33)
Patient hides pills
 No 41/109 (37.6%) 1.0
 Yes 5/13 (38.5%) 1.02 (0.48–2.11)
Takes ARV’s openly
 Yes 33/90 (36.7%) 1.0
 No 13/33 (39.4%) 1.07 (0.65–1.78)
Religious practices that interfere with treatment
 Yes 26/76 (34.2%) 1.0
 No 18/45 (40.0%) 1.17 (0.73–1.88)
Cultural practices that interfere with treatment
 No 35/100 (35.0%) 1.0
 Yes 12/23 (52.2%) 1.49 (0.93–2.39)
Feel sad/anxious
 No 28/82 (34.2%) 1.0
 Yes 22/42 (52.4%) 1.53 (1.01–2.33)
Cry frequently
 No 33/89 (37.1%) 1.0
 Yes 17/36 (47.2%) 1.27 (0.82–1.98)
Feel hopeless
 No 32/96 (33.3%) 1.0
 Yes 15/26 (57.7%) 1.73 (1.12–2.67)
Difficulty sleeping
 No 35/95 (36.8%) 1.0
 Yes 14/29 (48.3%) 1.31 (0.83–2.07)
Use alcohol to feel better
 No 41/111 (36.9%) 1.0
 Yes 7/12 (58.3%) 1.58 (0.92–2.70)
Any symptom suggestive of depression
 No 35/102 (34.3%) 1.0 1.0
 Yes 15/26 (57.7%) 1.68 (1.10–2.57) 1.05 (0.80–1.38)

Bold text p < 0.05. NRTI; nucleoside reverse transcriptase inhibitor. d4T; stavudine.; AZT; zidovudine. ABC; abacavir. TDF; tenofovir. TB; tuberculosis. ART; antiretroviral therapy. ARV; antiretroviral. VL; viral load. HIV; human immunodeficiency virus.

After adjusting for gender, age and viral load at first elevated viral load on second-line ART, none of the variables were associated with failure to suppress viral load. Despite this, four variables were prominent among those who failed to suppress. Compared to those who suppressed, more patients who failed to suppress reported living with family (44.2% vs. 23.7%; p = 0.048), missing a dose in the past week (53.3% vs. 30.0%; p = 0.010), using traditional/herbal medications (63.2% vs. 34.3%; p = 0.006) or any symptom suggestive of depression (57.7% vs. 34.3%; p = 0.017).

Discussion

Results from this study show that 61% of patients could suppress their viral load after IAC, which is consistent with other reports (Cox, 2015; Fox et al., 2016; Garone et al., 2013; Khan et al., 2014). Higher viral loads among those who failed to re-suppress supports the view that unresolved poor adherence, not drug resistance, drives second-line failure (Boyd et al., 2015; Ndahimana et al., 2016).

The main factors we identified undermining adherence in patients on second-line ART were patient-related factors such as use of traditional/herbal medicine and depression. We found that far more patients who failed to suppress reported living with family – which could suggest fear of stigmatization or poor family and social support which compromise adherence (Wood, Tobias, & McCree, 2004). In line with other reports, we found that having any symptom suggestive of depression was associated with failure to suppress viral load (Langebeek et al., 2014; Marconi et al., 2013). Our study also found that far more patients who failed to suppress reported using traditional/herbal medicine. However, the kind of herbal/traditional medicine a person was using was not documented in this study nor the reasons for taking them. A previous South African study conducted in South Africa showed the main reasons for taking these traditional/herbal medications was for pain relief, as an immune booster or to stop diarrhoea (Peltzer et al., 2011). Commonly used herbal medicines can result in drug-interactions with ART or reduce ART adherence (Kiguba, Karamagi, Ssali, Mugyenyi, & Katabira, 2007; Mills et al., 2005). Our study found that patients using traditional/herbal medication commonly (>60%) report missing doses or interrupting treatment.

As expected, poor adherence, in our study measured by a missed dose in the past week, was more common among those who failed to suppress. Results from this study and in line with other reports which have demonstrated a connection between poor adherence and elevated viral load (Ajose et al., 2012; Lima et al., 2008; Martin et al., 2008).

The findings should be considered in light of the study limitations. First, we did not have an objective measure of ART adherence (e.g., pill counts) or information relating to ART adherence. For example we did not have information on alcohol or drug use and did not measure factors such quality of healthcare services (e.g., lack of confidentiality and privacy, distance to clinic, drug stock outs, staff shortages etc.). Second, there was limited data to evaluate depression as a risk factor of failing second-line ART. In our study, any symptom of depression reported was used to classify a patient as possibly depressed. Therefore, it is possible that this may have led to misclassification. Third, 48% (144/298) of patients eligible for the study did not have an adherence counselling questionnaire and close to 17% (26/154) of patients included in the analysis did not have a repeat viral load. There were however no major differences observed between those included and not included in the analysis. Fourth, since the study only considers patients engaging in care, the factors identified and the estimate of adherence to ART may be different for those who are no longer in care. Lastly, it should be noted that we did not include information on drug resistance testing.

Conclusion

We demonstrate that patient-related factors (e.g., use of traditional/herbal medicine, depression, family/social support) and not necessarily provider-related factors, health system factors or treatment related factors contribute to poor adherence on second-line ART. Based on our findings, there is a need for on-going counselling and education of patients on second-line ART. Strategies to support patients, improved adherence evaluation and intensified monitoring need to be considered and evaluated in order to reduce the risk of virologic failure. Competing priorities and life circumstances can play a role in adherence and suppression, and should be taken into consideration when thinking through strategies or interventions to address these.

Acknowledgements

We acknowledge the directors and staff of Themba Lethu Clinic (TLC), Clinical HIV Research Unit (CHRU), HE2RO and Right to Care (RTC) – a PEPFAR (US President’s Emergency Plan for AIDS Relief) funded NGO, the Gauteng Provincial and National Department of Health for providing for the care of the patients at Themba Lethu Clinic as part of the National Comprehensive Care, Management and Treatment (CCMT) of HIV and AIDS program. Lastly, we would like to sincerely thank the patients attending the Themba Lethu Clinic for their continued trust in the treatment and care provided at the clinic.

Funding

MPF, DE, TS, CG and RB were supported through the South Africa Mission of the United States Agency for International Development (USAID) under the terms of Cooperative Agreement USAID-674-A-12-00029 to the Health Economics and Epidemiology Research Office. SD received a scholarship from Swedish International Development Cooperation Agency (SIDA; http://www.sida.org).

Footnotes

Disclosure statement

No potential conflict of interest was reported by the authors.

Publisher's Disclaimer: Disclaimer

This study is made possible by the generous support of the American people through Cooperative Agreement AID 674-A-12-00029 from the United States Agency for International Development (USAID). The contents of the aricle are the responsibility of the authors and do not necessarily reflect the views of USAID or the United States Government. The funders had no role in the study design, collection, analysis and interpretation of the data, in manuscript preparation of the decision to publish.

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