Augmenting maternal clinical cohort data with administrative laboratory dataset linkages: a validation study.

Background: The use of big data and large language models in healthcare can play a key role in improving patient treatment and healthcare management, especially when applied to large-scale administrative data. A major challenge to achieving this is ensuring that patient confidentiality and personal information is protected. One way to overcome this is by augmenting clinical data with administrative laboratory dataset linkages in order to avoid the use of demographic information. Methods: We explored an alternative method to examine patient files from a large administrative dataset in South Africa (the National Health Laboratory Services, or NHLS), by linking external data to the NHLS database using specimen barcodes associated with laboratory tests. This offers us with a deterministic way of performing data linkages without accessing demographic information. In this paper, we quantify the performance metrics of this approach. Results: The linkage of the large NHLS data to external hospital data using specimen barcodes achieved a 95% success. Out of the 1200 records in the validation sample, 87% were exact matches and 9% were matches with typographic correction. The remaining 5% were either complete mismatches or were due to duplicates in the administrative data. Conclusions: The high success rate indicates the reliability of using barcodes for linking data without demographic identifiers. Specimen barcodes are an effective tool for deterministic linking in health data, and may provide a method of creating large, linked data sets without compromising patient confidentiality.

Patterns of engagement in care during clients' first 12 months after HIV treatment initiation in South Africa: A retrospective cohort analysis using routinely collected data.

Retention on antiretroviral therapy (ART) during the early treatment period is one of the most serious challenges facing HIV programs, but the timing and patterns of early disengagement from care remain poorly understood. We describe patterns of engagement in HIV care during the first year after treatment initiation. We analysed retrospective datasets of routinely collected electronic medical register (EMR) data for ≥18-year-old clients who initiated ART at public sector clinics in South Africa after 01/01/2018 and had ≥14 months of potential follow-up. Using scheduled visit dates, we characterized engagement in care as continuous (no treatment interruption), cyclical (at least one visit >28 days late with a return visit observed) or disengaged (visit not attended and no evidence of return). We report 6- and 12-month patterns of retention in care and viral suppression. Among 35,830 participants (65% female, median age 33), in months 0-6, 59% were continuously in care, 14% had engaged cyclically, 11% had transferred to another facility, 1% had died, and 16% had disengaged from care at the initiating facility. Among disengagers in the first 6 months, 58% did not return after their initiation visit. By 12 months after initiation, the overall proportion disengaged was 23%, 45% were classified as continuously engaged in months 7-12, and only 38% of the cohort had maintained continuous engagement at both the 6- and 12-month endpoints. Participants who were cyclically engaged in months 0-6 were nearly twice as likely to disengage in months 7-12 as were continuous engagers in months 0-6 (relative risk 1.76, 95% CI:1.61-1.91) and were more likely to have an unsuppressed viral load by 12 months on ART (RR = 1.28; 95% CI1.13-1.44). The needs of continuous and cyclical engagers and those disengaging at different timepoints may vary and require different interventions or models of care.

Prior exposure to antiretroviral therapy among adult patients presenting for HIV treatment initiation or reinitiation in sub-Saharan Africa: a systematic review.

OBJECTIVES: As countries have scaled up access to antiretroviral therapy (ART) for HIV, attrition rates of up to 30% annually have created a large pool of individuals who initiate treatment with prior ART experience. Little is known about the proportion of non-naïve reinitiators within the population presenting for treatment initiation. DESIGN: Systematic review of published articles and abstracts reporting proportions of non-naïve adult patients initiating ART in sub-Saharan Africa. DATA SOURCES: PubMed, Embase Elsevier, Web of Science Core Collection, International AIDS Society conferences, Conference on Retroviruses and Opportunistic Infections conferences. ELIGIBILITY CRITERIA: Clinical trials and observational studies; reporting on adults in sub-Saharan Africa who initiated lifelong ART; published in English between 1 January 2018 and 11 July 2023 and with data collected after January 2016. Initiator self-report, laboratory discernment of antiretroviral metabolites, and viral suppression at initiation or in the medical record were accepted as evidence of prior exposure. DATA EXTRACTION AND SYNTHESIS: We captured study and sample characteristics, proportions with previous ART exposure and the indicator of previous exposure reported. We report results of each eligible study, estimate the risk of bias and identify gaps in the literature. RESULTS: Of 2740 articles, 11 articles describing 12 cohorts contained sufficient information for the review. Proportions of initiators with evidence of prior ART use ranged from 5% (self-report only) to 53% (presence of ART metabolites in hair or blood sample). The vast majority of screened studies did not report naïve/non-naïve status. Metrics used to determine and report non-naïve proportions were inconsistent and difficult to interpret. CONCLUSIONS: The proportion of patients initiating HIV treatment who are truly ART naïve is not well documented. It is likely that 20%-50% of ART patients who present for ART are reinitiators. Standard reporting metrics and diligence in reporting are needed, as is research to understand the reluctance of patients to report prior ART exposure. PROSPERO REGISTRATION NUMBER: CRD42022324136.

Change in body weight and risk of hypertension after switching from efavirenz to dolutegravir in adults living with HIV: evidence from routine care in Johannesburg, South Africa.

Background: The integrase strand transfer inhibitor (INSTI) dolutegravir is recommended in World Health Organization guidelines, but is associated with weight gain. We evaluated weight change in patients switching from efavirenz to dolutegravir in first-line antiretroviral therapy (ART) in Johannesburg, South Africa. Methods: We conducted a prospective cohort study of adults (≥16 years) of black African ancestry with HIV who initiated ART between January 2010-December 2020. Patients were propensity score-matched 1:1 (unexposed i.e. remaining on efavirenz: exposed i.e. switched from efavirenz to dolutegravir) on sex, age, months on ART, first ART regimen, haemoglobin, body mass index (BMI), blood pressure, viral load and CD4 count. We used linear regression to assess the effect of switching from efavirenz to dolutegravir on weight change and hypertension 12 months after exposure. Findings: We matched 794 patients switching to dolutegravir to 794 remaining on efavirenz. Exposed patients had a higher mean change in weight (1.78 kg; 95% confidence interval (CI):1.04,2.52 kg) from start of follow-up to 12 months vs. unexposed. We also found a 14.2 percentage point increase (95% CI: 10.6,17.7) in the risk of hypertension in those exposed to dolutegravir vs those that remained on efavirenz. Interpretation: In a real-world population, patients gained more weight and were at higher risk of hypertension after switching from efavirenz to dolutegravir than those remaining on efavirenz. Longer follow-up is needed, however, to determine if INSTI-associated weight gain is associated with changes in non-communicable disease risk over the long-term, or whether weight gain is sustained, as seen in clinical trials. Funding: This study has been made possible by the generous support of the American People and the President's Emergency Plan for AIDS Relief (PEPFAR) through the United States Agency for International Development (USAID), under the terms of cooperative agreement cooperative Agreement 72067419CA00004. In addition to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) 1K01MH105320-01A1.

Preferences for services in a patient's first six months on antiretroviral therapy for HIV in South Africa and Zambia (PREFER): research protocol for a prospective observational cohort study.

Background: For patients on HIV treatment in sub-Saharan Africa, the highest risk for loss from care remains the first six months after antiretroviral (ART) initiation, when patients are not yet eligible for differentiated service delivery (DSD) models that offer lower-burden, patient-centred care and thus improve treatment outcomes. To reduce early disengagement from care, the PREFER study will use a sequential mixed-methods approach to describe the characteristics, needs, concerns, and preferences of patients in South Africa and Zambia 0-6 months after ART initiation or re-initiation. Protocol: PREFER is an observational, prospective cohort study of adults on ART for ≤6 months at 12 public healthcare facilities in Zambia and 18 in South Africa. Its objective is to describe and understand the needs and preferences of initiating and re-initiating ART clients to inform the design of DSD models for the early HIV treatment period, improve early treatment outcomes, and distinguish the barriers encountered by naïve patients from those facing re-initiators. It has four components: 1) survey of clients 0-6 months after ART initiation (identify characteristics and preferences of clients starting ART); 2) follow up through routinely collected medical records for <24 months after enrollment (describe resource utilization and patterns and predictors of engagement in care); 3) focus group discussions and discrete choice experiment (explore reported barriers to and facilitators of retention); and 4) in South Africa only, collection of blood samples (assess the prevalence of ARV metabolites indicating prior ART use). Conclusions: PREFER aims to understand why the early treatment period is so challenging and how service delivery can be amended to address the obstacles that lead to early disengagement from care. It will generate information about client characteristics and preferences to help respond to patients' needs and design better strategies for service delivery and improve resource allocation going forward.

Cohort profile: the South African National Health Laboratory Service (NHLS) National HIV Cohort.

PURPOSE: South Africa's National Health Laboratory Service (NHLS) National HIV Cohort was established in 2015 to facilitate monitoring, evaluation and research on South Africa's National HIV Treatment Programme. In South Africa, 84.8% of people living with HIV know their HIV status; 70.7% who know their status are on ART; and 87.4% on ART are virologically suppressed. PARTICIPANTS: The NHLS National HIV Cohort includes the laboratory data of nearly all patients receiving HIV care in the public sector since April 2004. Patients are included in the cohort if they have received a CD4 count or HIV RNA viral load (VL) test. Using an anonymised unique patient identifier that we have developed and validated to linked test results, we observe patients prospectively through their laboratory results as they receive HIV care and treatment. Patients in HIV care are seen for laboratory monitoring every 6-12 months. Data collected include age, sex, facility location and test results for CD4 counts, VLs and laboratory tests used to screen for potential treatment complications. FINDINGS TO DATE: From April 2004 to April 2018, 63 million CD4 count and VL tests were conducted at 5483 facilities. 12.6 million unique patients had at least one CD4 count or VL, indicating they had accessed HIV care, and 7.1 million patients had a VL test indicating they had started antiretroviral therapy. The creation of NHLS National HIV Cohort has enabled longitudinal research on all lab-monitored patients in South Africa's national HIV programme, including analyses of (1) patient health at presentation; (2) care outcomes such as 'CD4 recovery', 'retention in care' and 'viral resuppression'; (3) patterns of transfer and re-entry into care; (4) facility-level variation in care outcomes; and (5) impacts of policies and guideline changes. FUTURE PLANS: Continuous updating of the cohort, integration with available clinical data, and expansion to include tuberculosis and other lab-monitored comorbidities.

Adolescent retention in HIV care within differentiated service-delivery models in sub-Saharan Africa.

Adolescents and young people living with HIV are at risk of disengaging from HIV care at all stages of the care cascade. Differentiated models of care offer simplified HIV-service delivery options in the hope of improving treatment outcomes, including retention on antiretroviral therapy. However, it remains unclear how successful and widespread these models are for adolescents in sub-Saharan Africa, where the burden of HIV is the greatest. Very few differentiated models of care specifically targeted to adolescents can be found and this priority group are currently ineligible from several models that exist. Where differentiated care has been made available to adolescents, data on the implementation and effectiveness of these interventions remain scarce. Despite this scarcity of evidence on the effectiveness of differentiated care among adolescent populations, several interventions, particularly community-based groups with peer navigators or supporters, might have potential to increase the reach, effectiveness, and adoption of differentiated care in adolescent HIV-care programmes.

Applying machine learning and predictive modeling to retention and viral suppression in South African HIV treatment cohorts.

HIV treatment programs face challenges in identifying patients at risk for loss-to-follow-up and uncontrolled viremia. We applied predictive machine learning algorithms to anonymised, patient-level HIV programmatic data from two districts in South Africa, 2016-2018. We developed patient risk scores for two outcomes: (1) visit attendance ≤ 28 days of the next scheduled clinic visit and (2) suppression of the next HIV viral load (VL). Demographic, clinical, behavioral and laboratory data were investigated in multiple models as predictor variables of attending the next scheduled visit and VL results at the next test. Three classification algorithms (logistical regression, random forest and AdaBoost) were evaluated for building predictive models. Data were randomly sampled on a 70/30 split into a training and test set. The training set included a balanced set of positive and negative examples from which the classification algorithm could learn. The predictor variable data from the unseen test set were given to the model, and each predicted outcome was scored against known outcomes. Finally, we estimated performance metrics for each model in terms of sensitivity, specificity, positive and negative predictive value and area under the curve (AUC). In total, 445,636 patients were included in the retention model and 363,977 in the VL model. The predictive metric (AUC) ranged from 0.69 for attendance at the next scheduled visit to 0.76 for VL suppression, suggesting that the model correctly classified whether a scheduled visit would be attended in 2 of 3 patients and whether the VL result at the next test would be suppressed in approximately 3 of 4 patients. Variables that were important predictors of both outcomes included prior late visits, number of prior VL tests, time since their last visit, number of visits on their current regimen, age, and treatment duration. For retention, the number of visits at the current facility and the details of the next appointment date were also predictors, while for VL suppression, other predictors included the range of the previous VL value. Machine learning can identify HIV patients at risk for disengagement and unsuppressed VL. Predictive modeling can improve the targeting of interventions through differentiated models of care before patients disengage from treatment programmes, increasing cost-effectiveness and improving patient outcomes.

One Pill, Once a Day: Simplified Treatment Regimens and Retention in HIV Care.

Simplified drug regimens may improve retention in care for persons with chronic diseases. In April 2013, South Africa adopted a once-daily single-pill human immunodeficiency virus (HIV) treatment regimen as the standard of care, replacing a multiple-pill regimen. Because the regimens had similar biological efficacy, the shift to single-pill therapy offered a real-world test of the impact of simplified drug-delivery mechanisms on patient behavior. Using a quasi-experimental regression discontinuity design, we assessed retention in care among patients starting HIV treatment just before and just after the guideline change. The study included 4,484 patients starting treatment at a large public sector clinic in Johannesburg, South Africa. The share of patients prescribed a single-pill regimen increased by over 40 percentage points between March and April 2013. Initiating treatment after the policy change was associated with 11.7-percentage-points' higher retention at 12 months (95% confidence interval: -2.2, 29.4). Findings were robust to different measures of retention, different bandwidths, and different statistical models. Patients starting treatment early in HIV infection-a key population in the test-and-treat era-experienced the greatest improvements in retention from single-pill regimens.

Assessment of facility-level antiretroviral treatment patient status utilizing a national-level laboratory cohort: Toward an understanding of system-level tracking and clinic switching in South Africa.

Background: Most estimates of HIV retention are derived at the clinic level through antiretroviral (ART) patient management systems, which capture ART clinic visit data, yet these cannot account for silent transfers across HIV treatment sites. Patient laboratory monitoring visits may also be observed in routinely collected laboratory data, which include ART monitoring tests such as CD4 count and HIV viral load, key to our work here. Methods: In this analysis, we utilized the NHLS National HIV Cohort (a system-wide viewpoint) to investigate the accuracy of facility-level estimates of retention in care for adult patients accessing care (defined using clinic visit data on patients under ART recorded in an electronic patient management system) at Themba Lethu Clinic (TLC). Furthermore, we describe patterns of facility switching among all patients and those patients classified as lost to follow-up (LTFU) at the facility level. Results: Of the 43,538 unique patients in the TLC dataset, we included 20,093 of 25,514 possible patient records (78.8%) in our analysis that were linked with the NHLS National Cohort, and we restricted the analytic sample to patients initiating ART between 1 January 2007 and 31 December 2017. Most (60%) patients were female, and the median age (IQR) at ART initiation was 37 (31-45) years. We found the laboratory records augmented retention estimates by a median of 860 additional active records (about 8% of all median active records across all years) from the facility viewpoint; this augmentation was more noticeable from the system-wide viewpoint, which added evidence of activity of about one-third of total active records in 2017. In 2017, we found 7.0% misclassification at the facility-level viewpoint, a gap which is potentially solvable through data integration/triangulation. We observed 1,134/20,093 (5.6%) silent transfers; these were noticeably more female and younger than the entire dataset. We also report the most common locations for clinic switching at a provincial level. Discussion: Integration of multiple data sources has the potential to reduce the misclassification of patients as being lost to care and help understand situations where clinic switching is common. This may help in prioritizing interventions that would assist patients moving between clinics and hopefully contribute to services that normalize formal transfers and fewer silent transfers.

Retention in care and viral suppression after same-day ART initiation: One-year outcomes of the SLATE I and II individually randomized clinical trials in South Africa.

INTRODUCTION: Same-day initiation (SDI) of antiretroviral therapy (ART) for HIV consistently increases ART uptake, but concerns remain about higher attrition from care after initiation. We analysed 12-month retention in the SLATE SDI trials. METHODS: SLATE I (Simplified Algorithms for Treatment Eligibility I, enrolment 06 March-28 July 2017) and SLATE II (enrolment 14 March-18 September 2018) were individually randomized trials at public outpatient clinics in Johannesburg that enrolled patients not yet on ART and administered the SLATE I or II algorithm. This included a symptom self-report, medical history, brief physical examination and readiness questionnaire to assess the eligibility for SDI. The studies compared the offer of SDI using the SLATE algorithms to standard of care initiation procedures. ART uptake and early retention were previously reported. Using routine clinic records, we conducted a pooled analysis of retention in care and HIV viral suppression 14 months after study enrolment, a time point equivalent to 12 months potential on ART, with an additional month allowed on either end to initiate ART and to return for the 12-month visit. RESULTS AND DISCUSSION: We enrolled 1193 study participants (standard arms, n = 599, 50%; intervention arms, n = 594, 50%) and analysed by originally assigned groups. By 14 months after enrolment, 50% of intervention arm patients and 46% of standard arm patients remained in care at the initiating site (crude risk difference 4% (95% confidence interval -1%-10%); crude relative risk 1.10 (0.97-1.23), with similar viral suppression between arms. Observed attrition from care at site by 14 months was high in both study arms, but we found no evidence that the offer of SDI led to greater overall attrition or lower rates of viral suppression 1 year after starting ART and may have generated small improvements. SDI may have shifted some attrition from before to after dispensing of the first dose of medication. CONCLUSIONS: An offer of SDI of ART, following a carefully designed protocol to identify patients who are eligible and ready to start treatment, is not inherently associated with an overall increase in patient attrition from care and leads to similar rates of viral suppression. TRIAL REGISTRATION: Clinicaltrials.gov NCT02891135, registered 01 September 2016. First participant enrolled 06 March 2017 in South Africa. Clinicaltrials.gov NCT03315013, registered 19 October 2017. First participant enrolled 14 March 2018.

Variation in HIV care and treatment outcomes by facility in South Africa, 2011-2015: A cohort study.

BACKGROUND: Despite widespread availability of HIV treatment, patient outcomes differ across facilities. We propose and evaluate an approach to measure quality of HIV care at health facilities in South Africa's national HIV program using routine laboratory data. METHODS AND FINDINGS: Data were extracted from South Africa's National Health Laboratory Service (NHLS) Corporate Data Warehouse. All CD4 counts, viral loads (VLs), and other laboratory tests used in HIV monitoring were linked, creating a validated patient identifier. We constructed longitudinal HIV care cascades for all patients in the national HIV program, excluding data from the Western Cape and very small facilities. We then estimated for each facility in each year (2011 to 2015) the following cascade measures identified a priori as reflecting quality of HIV care: median CD4 count among new patients; retention 12 months after presentation; 12-month retention among patients established in care; viral suppression; CD4 recovery; monitoring after an elevated VL. We used factor analysis to identify an underlying measure of quality of care, and we assessed the persistence of this quality measure over time. We then assessed spatiotemporal variation and facility and population predictors in a multivariable regression context. We analyzed data on 3,265 facilities with a median (IQR) annual size of 441 (189 to 988) lab-monitored HIV patients. Retention 12 months after presentation increased from 42% to 47% during the study period, and viral suppression increased from 66% to 79%, although there was substantial variability across facilities. We identified an underlying measure of quality of HIV care that correlated with all cascade measures except median CD4 count at presentation. Averaging across the 5 years of data, this quality score attained a reliability of 0.84. Quality was higher for clinics (versus hospitals), in rural (versus urban) areas, and for larger facilities. Quality was lower in high-poverty areas but was not independently associated with percent Black. Quality increased by 0.49 (95% CI 0.46 to 0.53) standard deviations from 2011 to 2015, and there was evidence of geospatial autocorrelation (p < 0.001). The study's limitations include an inability to fully adjust for underlying patient risk, reliance on laboratory data which do not capture all relevant domains of quality, potential for errors in record linkage, and the omission of Western Cape. CONCLUSIONS: We observed persistent differences in HIV care and treatment outcomes across South African facilities. Targeting low-performing facilities for additional support could reduce overall burden of disease.

Attrition in HIV care following HIV diagnosis: a comparison of the pre-UTT and UTT eras in South Africa.

INTRODUCTION: Policies for Universal Test & Treat (UTT) and same-day initiation (SDI) of antiretroviral therapy (ART) were instituted in South Africa in September 2016 and 2017 respectively. However, there is limited evidence on whether these changes have improved patient retention after HIV diagnosis. METHODS: We enrolled three cohorts of newly diagnosed HIV-infected adults from two primary health clinics in Johannesburg from April to November 2015 (Pre-UTT, N = 144), May-September 2017 (UTT, N = 178) and October-December 2017 (SDI, N = 88). A baseline survey was administered immediately after HIV diagnosis after which follow-up using clinical records (paper charts, electronic health records and laboratory data) ensued for 12 months. The primary outcome was patient loss to follow-up (being >90 days late for the last scheduled appointment) at 12 months post-HIV diagnosis. We modelled attrition across HIV policy periods with Cox proportional hazard regression. RESULTS: Overall, 410 of 580 screened HIV-positive patients were enrolled. Overall, attrition at 12 months was 30% lower in the UTT guideline period (38.2%) compared to pre-UTT (47.2%, aHR 0.7, 95% CI: 0.5 to 1.0). However, the total attrition was similar between the SDI (47.7%) and pre-UTT cohorts (aHR 1.0, 95% CI: 0.7 to 1.5). Older age at HIV diagnosis (aHR 0.5 for ≥40 vs. 25 to 29 years, 95% CI: 0.3 to 0.8) and being in a non-marital relationship (aHR 0.5 vs. being single, 95% CI: 0.3 to 0.8) protected against LTFU at 12 months, whereas LTFU rates increased with longer travel time to the diagnosing clinic (aHR 1.8 for ≥30 minutes vs. ≤15 minutes, 95% CI: 1.1 to 3.1). In analyses adjusted for the time-varying ART initiation status, compared to the pre-ART period of care, the hazard of on-ART LTFU was 90% higher among participants diagnosed under the SDI policy compared to pre-UTT (aHR 1.9, 95% CI: 1.1 to 2.9). CONCLUSIONS: Overall, nearly two-fifths of HIV positive patients are likely to disengage from care by 12 months after HIV diagnosis under the new SDI policy. Furthermore, the increase in on-ART patient attrition after the introduction of the SDI policy is cause for concern. Further research is needed to determine the best way for rapidly initiating patients on ART and also reducing long-term attrition from care.

Patient Perspectives of Quality of the Same-Day Antiretroviral Therapy Initiation Process in Gauteng Province, South Africa: Qualitative Dominant Mixed-Methods Analysis of the SLATE II Trial.

BACKGROUND: HIV patients in South Africa continue to report operational barriers to starting antiretroviral therapy (ART). In the Simplified Algorithm for Treatment Eligibility (SLATE) II trial, same-day initiation (SDI) of ART increased the number of patients commencing ART and achieving HIV viral suppression by using a screening tool to distinguish between patients eligible for SDI and those requiring additional care before starting treatment. We conducted a mixed-methods evaluation to explore trial patients' perceptions and experiences of SDI. METHODS: SLATE II was implemented at three urban, public primary health care clinics in Gauteng Province, South Africa. We conducted a short quantitative survey and in-depth interviews among a purposive sample of 89 of the 593 trial participants in the intervention and standard arms, using a mixed inductive-deductive framework approach. RESULTS: Nearly all respondents (95%) were satisfied with their care, despite reporting clinic wait times of ≥ 3 h (72%). Intervention patients found the initiation process to be easy; standard patients found it complicated and were frustrated with being shuffled around the clinic. No intervention arm patients felt that SDI was "too fast" or indicated a preference for a more gradual process. Both groups highlighted the need for good counselling and non-judgmental, respectful staff. Standard patients suggested improving patient-provider relations, strengthening counselling, reducing wait times, and minimising referrals. CONCLUSIONS: While it is difficult to untangle the role of providers from that of the SLATE algorithm in influencing patient experiences, adoption of SLATE II implementation procedures could improve patient experience of treatment initiation. TRIAL REGISTRATION: Clinicaltrials.gov NCT03315013, registered October 19, 2017.

The South African National HIV Pregnancy Cohort: evaluating continuity of care among women living with HIV.

BACKGROUND: South Africa is home to more people living with HIV than any other country, including nearly one in three pregnant women attending antenatal care. Access to antiretroviral therapy (ART) has increased substantially since the start of the national ART program in 2004, with > 95% ART coverage during pregnancy and delivery, and vertical transmission of HIV greatly reduced. However, women who initiate ART during pregnancy are at heightened risk of dropping out of care, particularly after delivery, leading to the potential for viral transmission, morbidity and mortality. It is difficult to evaluate the success of policies of expanded access to ART care, and assess continuity of care, due to the lack of a national longitudinal HIV care database. Also, patient movement between unlinked facilities. For the first time on a national level, we propose to utilize routinely-collected laboratory data to develop and validate a cohort of pregnant women living with HIV in South Africa in a way that is uniquely robust to facility transfer. METHODS: Using laboratory test data matched to facility type, we will identify entry to antenatal care to build the cohort, then describe key treatment milestones, including 1) engagement in antenatal care, 2) initiation of ART, 3) HIV viremia, and 4) continuity of HIV care in the postpartum period. Second, we will measure the effect of system-wide factors impacting continuity of care among pregnant women. We will assess policies of expanded treatment access on continuity of care using regression-discontinuity analyses. We then will assess mobility and its effect on continuity of care during and after pregnancy. Third, we will identify individual-level risk factors for loss from HIV care in order to develop targeted interventions to improve engagement in HIV care. DISCUSSION: This work will create the world's largest national cohort of pregnant women living with HIV. This novel cohort will be a powerful tool available to policymakers, clinicians and researchers for improving our understanding of engagement in care among pregnant women in South Africa and assessing the performance of the South African national ART program in caring for pregnant women living with HIV. TRIAL REGISTRATION: N/A (not a clinical trial).

Prevalence of TB symptoms, diagnosis and treatment among people living with HIV (PLHIV) not on ART presenting at outpatient clinics in South Africa and Kenya: baseline results from a clinical trial.

OBJECTIVE: We used screening data and routine clinic records for intervention arm patients in the Simplified Algorithm for Treatment Eligibility (SLATE) trials to describe the prevalence of tuberculosis (TB) symptoms, diagnosis and treatment among people living with HIV (PLHIV), not on antiretroviral therapy (ART) and presenting at outpatient clinics in South Africa and Kenya. We compared the performance of the WHO four-symptom TB screening tool with a baseline Xpert test. SETTING: Outpatient HIV clinics in South Africa and Kenya. PARTICIPANTS: Eligible patients were non-pregnant, PLHIV, >18 years of age, not on ART, willing to provide written informed consent. A total of 594 patients in South Africa and 240 in Kenya were eligible. RESULTS: Prevalence of any TB symptom was 38% in Kenya, 35% (SLATE I) and 47% (SLATE II) in South Africa. During SLATE I, 70% of patients in Kenya and 57% in South Africa with ≥1 TB symptom were tested for TB. In SLATE II, 79% of patients with ≥1 TB symptom were tested. Of those, 19% tested positive for TB in Kenya, 15% (SLATE I) and 5% (SLATE II) tested positive in South Africa. Of the 28 patients who tested positive in both trials, 20 initiated TB treatment. The lowest median CD4 counts were among those with active TB (Kenya 124 cells/mm3; South Africa 193 cells/mm3). When comparing the WHO four-symptom screening tool to the Xpert test (SLATE II), we found that increasing the number of symptoms required for a positive screen from one to three or four decreased sensitivity but increased the positive predictive value to >30%. CONCLUSIONS: 80% of patients assessed for ART initiation presented with ≥1 TB symptoms. Reconsideration of the 'any symptom' rule may be appropriate, with ART initiation among patients with fewer/milder symptoms commencing while TB test results are pending. TRIAL REGISTRATION NUMBER: NCT02891135 and NCT03315013.

A clinical algorithm for same-day HIV treatment initiation in settings with high TB symptom prevalence in South Africa: The SLATE II individually randomized clinical trial.

BACKGROUND: Many countries encourage same-day initiation of antiretroviral therapy (ART), but evidence on eligibility for same-day initiation, how best to implement it, and its impact on outcomes remains scarce. Building on the Simplified Algorithm for Treatment Eligibility (SLATE) I trial, in which nearly half of participants were ineligible for same-day initiation mainly because of TB symptoms, the study evaluated the revised SLATE II algorithm, which allowed same-day initiation for patients with mild TB symptoms and other less serious reasons for delay. METHODS AND FINDINGS: SLATE II was a nonblinded, 1:1 individually randomized pragmatic trial at three primary healthcare clinics in Johannesburg, South Africa. It randomized adult patients presenting for an HIV test or any HIV care but not yet on ART. Intervention arm patients were assessed with a symptom screen, medical history, brief physical examination, and readiness questionnaire to distinguish between patients eligible for immediate ART dispensing and those requiring further care before initiation. Standard arm patients received usual care. Follow-up was by review of routine clinic records. Primary outcomes were (1) ART initiation in ≤7 days and (2) ART initiation in ≤28 days and retention in care at 8 months (composite outcome). From 14 March to 18 September 2018, 593 adult HIV+, nonpregnant patients were enrolled (median interquartile range [IQR] age 35 [29-43]; 63% (n = 373) female; median CD4 count 293 [133-487]). Half of study patients (n = 295) presented with TB symptoms, whereas only 13 (4%) standard arm and 7 (2%) intervention arm patients tested positive for TB disease. Among 140 intervention arm patients with TB symptoms, 72% were eligible for same-day initiation. Initiation was higher in the intervention (n = 296) versus standard arm (n = 297) by 7 days (91% versus 68%; risk difference [RD] 23% [95% confidence interval (CI) 17%-29%]) and 28 days (94% versus 82%; RD 12% [7%-17%]) after enrollment. In total, 87% of intervention and 38% of standard arm patients initiated on the same day. By 8 months after study enrollment, 74% (220/296) of intervention and 59% (175/297) of standard arm patients had both initiated ART in ≤28 days and been retained in care (RD 15% [7%-23%]). Among the 41% of participants with viral load results available, suppression was 90% in the standard arm and 92% in the intervention arm among patients initiated in ≤28 days. No ART-associated adverse events were reported after initiation; two intervention and four standard arm patients were reported to have died during passive follow-up. Limitations of the study included limited geographic generalizability, exclusion of patients too sick to consent, fluctuations in procedures in the standard arm over the course of the study, high fidelity to the trial protocol by study staff, and the possibility of overestimating loss to follow-up due to data constraints. CONCLUSIONS: More than 85% of patients presenting for HIV testing or care, including those newly diagnosed, were eligible and ready for same-day initiation under the SLATE II algorithm. The algorithm increased initiation within 7 days without appearing to compromise retention and viral suppression at 8 months, offering a practical and acceptable approach that can be widely and immediately utilized by existing providers. TRIAL REGISTRATION: Clinicaltrials.gov NCT03315013, registered 19 October 2017. First participant enrolled 14 March 2018.

Impact of Viral Load Monitoring on Retention and Viral Suppression: A Regression Discontinuity Analysis of South Africa's National Laboratory Cohort.

South African guidelines recommend repeat viral load testing within 6 months when human immunodeficiency virus (HIV) viral loads exceed 1,000 copies/mL. We assessed whether South African facilities follow viral load monitoring guidelines and whether guidelines improve HIV-related outcomes, using a regression discontinuity design in a national HIV cohort of 174,574 patients (2013-2015). We assessed whether patients with viral loads just above versus just below 1,000 copies/mL were more likely to receive repeat testing in 6 months, and we compared differences in clinic transfers, retention, and viral suppression. The majority (67%) of patients with viral loads of >1,000 copies/mL did not receive repeat testing within 6 months, and these patients were 8.0% (95% confidence interval (CI): 6.2, 9.7) more likely to receive repeat testing compared with ≤1,000 copies/mL. Eligibility for repeat testing (>1,000 copies/mL) was associated with greater 12-month retention (risk difference = 2.9%, 95% CI: 0.6, 5.2) and combined suppression and retention (risk difference = 5.8%, 95% CI: 3.0, 8.6). Patients with viral loads of >1,000 copies/mL who actually received repeat testing were 85.2% more likely to be both retained and virally suppressed at 12 months (95% CI: 35.9, 100.0). Viral load monitoring might improve patient outcomes, but most patients with elevated viral loads do not receive monitoring within recommended timelines.

Delays in repeat HIV viral load testing for those with elevated viral loads: a national perspective from South Africa.

INTRODUCTION: In South Africa, HIV patients with an elevated viral load (VL) should receive repeat VL testing after adherence counselling. We set out to use a national HIV Cohort to describe time to repeat viral load testing across South Africa and identify predictors of time to repeat testing. METHODS: We conducted a cohort study of prospectively collected laboratory data. HIV treatment guidelines have changed over time in South Africa, but call for repeat VL testing within six months if 400 to 1000 copies/mL and two to three months if >1000 copies/mL. We included patients with suppressed viral loads (indicating they are on ART) and a first elevated VL (>400 copies/mL) between April 2004 and December 2014. Follow-up began at first elevated VL and continued until repeat testing, loss to follow-up or December 2016. We calculated adjusted hazard ratios (aHR) using Cox proportional hazard models. RESULTS: Of 371,648 patients with a VL > 400, 83.9% (311,790) had a repeat VL, in a median (IQR) of 7.0 (4.1 to 12.2) months. Of those with a first viral load 400 to 1000 copies/mL, 56.4% had a repeat VL within guideline recommended six months (defined as up to nine months), whereas among those >1000 copies/mL only 47.7% had a repeat viral load within guideline recommended two to three months (defined as up to six months). We found a small increase in repeat testing associated with higher VL value (aHR 1.11; 95% CI: 1.10 to 1.12 comparing >1000 vs 400 to 1000 copies/mL) and very low CD4 counts at first elevated VL (aHR 1.16; 95% CI: 1.13 to 1.19 comparing CD4 < 50 vs <500 cells/mm3 ). We also found strong variation in time to repeat VL testing by province. CONCLUSIONS: Median time to repeat viral load testing for those with an elevated viral load was longer than guidelines recommend. Future work should identify whether delays are due to patient or provider factors.