Future HIV epidemic trajectories in South Africa and projected long-term consequences of reductions in general population HIV testing: a mathematical modelling study

BACKGROUND

After successful intensive interventions to rapidly increase HIV awareness, coverage of antiretroviral therapy (ART), and viral suppression, HIV programmes in eastern and southern Africa are considering scaling back of some interventions, such as widespread general population HIV testing. We aimed to model whether scaling back of general population HIV testing in South Africa could result in a resurgence of the HIV epidemic or substantial slowing of declines in HIV incidence, resulting in increased long-term ART.

METHODS

In this modelling study, we used the Thembisa 4.5 model (a deterministic compartmental model of HIV transmission in South Africa) to project the South African HIV epidemic to 2100 assuming the continuation of 2022 epidemiological conditions and HIV programme implementation. We assessed how implementing reductions in general population HIV testing services in 2025 (while maintaining antenatal, symptom-based, and risk-based testing modalities and other HIV prevention services at 2022 levels) would affect HIV incidence and prevalence among people aged 15-49 years, the year in which incidence would reach one per 1000 people aged 15-49 years (the threshold for virtual elimination of HIV), and associated costs, as well as numbers of additional new HIV infections and AIDS-related deaths. We also modelled the effects of delaying reductions in general population testing services by 5-year increments. Additionally, we modelled the potential effects of reductions in general population testing services in combination with increases or decreases in ART interruption rates (ie, the annual rate at which people who are on ART discontinue ART) and condom usage in 2025-35.

FINDINGS

If general population HIV testing services and the HIV risk environment of 2022 were maintained, we projected that HIV incidence would steadily decline from 4·95 (95% CI 4·40-5·34) per 1000 population in 2025 to 0·14 (0·05-0·31) per 1000 in 2100, and that the so-called virtual elimination threshold of less than one new infection per 1000 population per year would be reached in 2055 (95% CI 2051-2060). Scaling back of general population HIV testing services by 25%, 50%, or 75% in 2025 delayed time to reaching the virtual elimination threshold by 5, 13, or 35 years, respectively, whereas complete cessation of general population testing would result in the threshold not being attained by 2100. Although the incidence of HIV continued to fall when general HIV testing services were reduced, our modelling suggested that, with reductions of between 25% and 100%, between 396 000 (95% CI 299 000-474 000) and 2·50 million (1·97 million-2·98 million) additional HIV infections and between 115 000 (94 000-135 000) and 795 000 (670 000-926 000) additional AIDS-related deaths would occur between 2025 and 2075, depending on the extent of reduction in testing. Delaying reductions in general population HIV testing services for 5-25 years mitigated some of these effects. HIV testing accounted for only 5% of total programmatic costs at baseline; reducing testing moderately reduced short-term total annual costs, but increased annual costs after 25 years. Increases in ART interruption and reductions in condom usage were projected to slow the decline in incidence and increase the coverage of general HIV testing services required to control transmission but did not cause rapid resurgence in HIV infections.

INTERPRETATION

Our modelling suggests that scaling back of general population HIV testing would not result in a resurgence of HIV infections, but would delay attainment of incidence-reduction targets and result in long-term increases in HIV infections, AIDS-related deaths, and costs (via increased need for ART provision). HIV programmes need to balance short-term potential resource savings with long-term epidemic control objectives.

FUNDING

Bill & Melinda Gates Foundation.

The potential benefits of long-acting injectable cabotegravir in pregnant and breastfeeding women and their infants

BACKGROUND

Pregnant and breastfeeding women (PBW) in sub-Saharan Africa have high HIV incidence rates and associated risk of vertical transmission to their infants. Oral preexposure prophylaxis (PrEP) and injectable PrEP (long-acting cabotegravir, or CAB-LA) can potentially reduce this HIV transmission, but population-level impacts are uncertain.

METHODS

We extended a previously developed model of HIV and PrEP in South Africa to allow for variable PrEP duration and preference in PBW. We considered three potential scenarios for PrEP provision to PBW: oral PrEP only, CAB-LA only, and allowing oral/CAB-LA choice, with uptake and retention assumptions informed by South African data, each compared with a 'base' scenario without PrEP for PBW.

RESULTS

Without PrEP for PBW, the model estimates 1.31 million new infections will occur between 2025 and 2035 in South African adults and children, including 100 000 in PBW, 16 800 in infants at/before birth, and 35 200 in children through breastmilk. In the oral PrEP-only scenario, these numbers would reduce by 1.2% (95% CI: 0.7-1.7%), 8.6% (4.8-12.9%), 4.0% (2.1-5.8%), and 5.3% (3.0-8.2%) respectively. In the CAB-LA-only scenario, the corresponding reductions would be 6.1% (2.9-9.6%), 41.2% (19.8-65.0%), 12.6% (6.0-19.4%), and 29.5% (13.9-46.8%), respectively, and in the oral/CAB-LA choice scenario, similar reductions would be achieved [5.6% (3.4-8.0%), 39% (23.4-55.9%), 12.4% (7.4-16.8%) and 27.6% (16.5-39.9%) respectively].

CONCLUSION

CAB-LA has the potential to be substantially more effective than oral PrEP in preventing HIV acquisition in PBW and vertical transmission, and can also modestly reduce HIV incidence at a population level.

Lip, oral and oropharyngeal cancer incidence among Aboriginal and Torres Strait Islander Peoples: First report from Australian population-based cancer registry, 1999-2018

BACKGROUND

The Australian Burden of Disease Study has shown that cancer is the single most important entity responsible for the greatest cause of health burden in Australia. Unfortunately, Aboriginal and Torres Strait Islander peoples experience a greater burden of this disease, with cancer of the lung, breast, bowel and prostrate being the most common. Lip, oral cavity and pharyngeal cancer incidence is rapidly rising globally and is now the sixth most common cancer in Australia. This paper aims to summarize, for the first time, the incidence and prevalence trends of lip, oral cavity and pharyngeal cancers in Aboriginal and Torres Strait Islander Australians.

METHODS

Data were obtained from the Australian Cancer Database (ACD), which is compiled at the Australian Institute of Health and Welfare (AIHW) from 1999 to 2018 to estimate the incidence and prevalence of certain head and neck cancers (ICD-10 codes C00-C10, C14). The other variables requested were age groups and sex.

RESULTS

Results were stratified by ICD-10 code, sex and age group at diagnosis and time period (i.e. grouped years of diagnosis). The total incidence of lip, oral cavity and pharyngeal cancers increased by 1.3 times from 1999 to 2008 (107/100 000) to 2009-2018 (135/100 000). The overall 5-year prevalence of lip, oral cavity and pharyngeal cancers was 0.17% (0.24% for men and 0.09% for women).

CONCLUSIONS

The significantly increased incidence of lip, oral cavity and pharyngeal cancers in Aboriginal and Torres Strait Islander peoples in Australia is concerning and should be explored. A targeted, comprehensive and culturally safe model of care for Aboriginal and Torres Strait Islander peoples with lip, oral cavity and pharyngeal cancers is imperative.

A quantitative assessment of the consistency of projections from five mathematical models of the HIV epidemic in South Africa: a model comparison study

BACKGROUND

Mathematical models are increasingly used to inform HIV policy and planning. Comparing estimates obtained using different mathematical models can test the robustness of estimates and highlight research gaps. As part of a larger project aiming to determine the optimal allocation of funding for HIV services, in this study we compare projections from five mathematical models of the HIV epidemic in South Africa: EMOD-HIV, Goals, HIV-Synthesis, Optima, and Thembisa.

METHODS

The five modelling groups produced estimates of the total population, HIV incidence, HIV prevalence, proportion of people living with HIV who are diagnosed, ART coverage, proportion of those on ART who are virally suppressed, AIDS-related deaths, total deaths, and the proportion of adult males who are circumcised. Estimates were made under a "status quo" scenario for the period 1990 to 2040. For each output variable we assessed the consistency of model estimates by calculating the coefficient of variation and examining the trend over time.

RESULTS

For most outputs there was significant inter-model variability between 1990 and 2005, when limited data was available for calibration, good consistency from 2005 to 2025, and increasing variability towards the end of the projection period. Estimates of HIV incidence, deaths in people living with HIV, and total deaths displayed the largest long-term variability, with standard deviations between 35 and 65% of the cross-model means. Despite this variability, all models predicted a gradual decline in HIV incidence in the long-term. Projections related to the UNAIDS 95-95-95 targets were more consistent, with the coefficients of variation below 0.1 for all groups except children.

CONCLUSIONS

While models produced consistent estimates for several outputs, there are areas of variability that should be investigated. This is important if projections are to be used in subsequent cost-effectiveness studies.

Oral health profile of Australian children from different immigrant backgrounds

OBJECTIVES

To profile the oral health of Australian children from different immigrant backgrounds.

METHOD

Cross-sectional data for Australian children were obtained from the 2012-14 National Child Oral Health Study (NCOHS). Three categories of immigrant status were created based on parents' country of birth and language (non-immigrant, non-visible immigrant, and visible immigrant). Descriptive analyses reported weighted estimates for experience of dental caries, self-rated oral health, and dental services utilisation separately for children aged 5-9 years and 10-14 years.

RESULTS

The sample comprised 10,610 children aged 5-9 years (3,605 from immigrant backgrounds), and 8,741 children aged 10-14 years (3,074 from immigrant backgrounds). Children from non-visible immigrant backgrounds presented worse dental service utilisation and poorer self-rated oral health than children from non-immigrant and visible immigrant families. Greater inequalities in dental caries experience were observed in the 5-9-year-olds. Untreated caries was substantially higher among visible immigrant children aged 5-9 years (38.8%, 95% CI: 35.5-42.3) than non-immigrant (24.9%, 95% CI: 23.4-26.6) and non-visible immigrant children (21.0%, 95% CI: 17.7-24.7).

CONCLUSIONS

Australian children from immigrant families constitute a highly heterogeneous group with substantial discrepancies in oral health outcomes.

Early Childhood Caries Intervention in Aboriginal Australian Children: A Cross-in Randomized Trial

INTRODUCTION

Early childhood caries (ECC) is the strongest predictor of dental caries in adulthood. Indigenous children have higher levels of ECC compared with non-Indigenous children. The study aimed to estimate the efficacy of an ECC intervention among Aboriginal Australian children.

METHODS

Baby Teeth Talk was an outcome assessor-blinded, closed-cohort cross-in randomized controlled trial conducted in South Australia, Australia. We randomly allocated 448 women pregnant with an Aboriginal child to either an immediate (II) or delayed (DI) intervention group between January 2011 and May 2012. The immediate intervention comprised (1) provision of dental care to mothers during pregnancy; (2) application of fluoride varnish to teeth of children at ages 6, 12; and 18 mo; (3) motivational interviewing delivered in conjunction; and (4) anticipatory guidance. Mothers/children in the DI group received the same intervention commencing when the child was 24 mo of age. The outcomes were assessed by the number of decayed, missing, and filled teeth (dmft) in children aged 24, 36, and 60 mo. Regression-based approaches with generalized linear mixed effect (log-Poisson) model characterized the mean dmft to estimate risk ratios (RRs) and 95% confidence intervals (95% CIs).

RESULTS

A total of 223 participants were randomly allocated to the II group and 225 to the DI group. Three hundred sixty-five children (178 II, 187 DI) received at least 1 dental clinical examination at 24, 36, and 60 mo of follow-up. The mean dmft was lower in the II group (0.48, 1.32, and 2.06) than in the DI group (0.82, 1.90, and 3.29) at each time point, respectively. The direct ECC intervention effect was to prevent/decrease dental decay experience (dmft) occurrence by 84% (RR = 1.84, 95% CI: 1.20-2.48) after adjusting for all covariates.

CONCLUSIONS

Our analysis indicated that the time-varied ECC intervention had immediate and longer-term effects on the prevention of ECC among Indigenous Australian children.

KNOWLEDGE TRANSFER STATEMENT

The study aimed to estimate the efficacy of an early childhood caries (ECC) intervention among Aboriginal Australian children. The findings indicated that the culturally appropriate ECC intervention is effective for the preventive of ECC and can be used by clinicians, educators, and policy makers when planning an ECC intervention, so as to prevent and reduce ECC and meet identified oral health needs across the Australian population, which is important for preventive dental care.

The role of modelling and analytics in South African COVID-19 planning and budgeting

BACKGROUND

The South African COVID-19 Modelling Consortium (SACMC) was established in late March 2020 to support planning and budgeting for COVID-19 related healthcare in South Africa. We developed several tools in response to the needs of decision makers in the different stages of the epidemic, allowing the South African government to plan several months ahead.

METHODS

Our tools included epidemic projection models, several cost and budget impact models, and online dashboards to help government and the public visualise our projections, track case development and forecast hospital admissions. Information on new variants, including Delta and Omicron, were incorporated in real time to allow the shifting of scarce resources when necessary.

RESULTS

Given the rapidly changing nature of the outbreak globally and in South Africa, the model projections were updated regularly. The updates reflected 1) the changing policy priorities over the course of the epidemic; 2) the availability of new data from South African data systems; and 3) the evolving response to COVID-19 in South Africa, such as changes in lockdown levels and ensuing mobility and contact rates, testing and contact tracing strategies and hospitalisation criteria. Insights into population behaviour required updates by incorporating notions of behavioural heterogeneity and behavioural responses to observed changes in mortality. We incorporated these aspects into developing scenarios for the third wave and developed additional methodology that allowed us to forecast required inpatient capacity. Finally, real-time analyses of the most important characteristics of the Omicron variant first identified in South Africa in November 2021 allowed us to advise policymakers early in the fourth wave that a relatively lower admission rate was likely.

CONCLUSION

The SACMC's models, developed rapidly in an emergency setting and regularly updated with local data, supported national and provincial government to plan several months ahead, expand hospital capacity when needed, allocate budgets and procure additional resources where possible. Across four waves of COVID-19 cases, the SACMC continued to serve the planning needs of the government, tracking waves and supporting the national vaccine rollout.

What will it take for an injectable ARV to change the face of the HIV epidemic in high-prevalence countries? Considerations regarding drug costs and operations

INTRODUCTION

The proven effectiveness of injectable cabotegravir (CAB-LA) is higher than that of any other HIV prevention intervention ever trialled or implemented, surpassing medical male circumcision, condoms and combination antiretroviral treatment. Based on our own analyses and experience with the South African oral pre-exposure prophylaxis (PrEP) programme, we review the supply and demand side factors that would need to be in place for a successful rollout of CAB-LA, and delineate lessons for the launch of other long-acting and extended delivery (LAED) antiretroviral drugs.

DISCUSSION

On the supply side, CAB-LA will have to be offered at a price that makes the drug affordable and cost-effective to low- and middle-income countries, especially those with high HIV prevalence. An important factor in lowering prices is a guaranteed market volume, which in turn necessitates the involvement of large funders, such as PEPFAR and the Global Fund, and a fairly rapid scale-up of the drug. Such a scale-up would have to involve speedy regulatory approval and WHO pre-qualification, swift integration of CAB-LA into national guidelines and planning for large enough manufacturing capacity, including the enabling of local manufacture. On the demand side, existing demand for HIV prevention products has to be harnessed and additional demand created, which will be aided by designing CAB-LA programmes at the primary healthcare or community level, and involving non-traditional outlets, such as private pharmacies and doctors' practices.

CONCLUSIONS

CAB-LA could be the game changer for HIV prevention that we have been hoping for, and serve as a useful pilot for other LAEDs. A successful rollout would involve building markets of a guaranteed size; lowering the drug's price to a level possibly below the cost of production, while also lowering the cost of production altogether; harnessing, creating and sustaining demand for the product over the long term, wherever possible, in national programmes rather than single demonstration sites; and establishing and maintaining manufacturing capacity and supply chains. For this, all parties have to work together-including originator and generic manufacturers, donor organizations and other large funders, and the governments of low- and middle-income countries, in particular those with high HIV prevalence.

The National COVID-19 Epi Model (NCEM): Estimating cases, admissions and deaths for the first wave of COVID-19 in South Africa

In March 2020 the South African COVID-19 Modelling Consortium was formed to support government planning for COVID-19 cases and related healthcare. Models were developed jointly by local disease modelling groups to estimate cases, resource needs and deaths due to COVID-19. The National COVID-19 Epi Model (NCEM) while initially developed as a deterministic compartmental model of SARS-Cov-2 transmission in the nine provinces of South Africa, was adapted several times over the course of the first wave of infection in response to emerging local data and changing needs of government. By the end of the first wave, the NCEM had developed into a stochastic, spatially-explicit compartmental transmission model to estimate the total and reported incidence of COVID-19 across the 52 districts of South Africa. The model adopted a generalised Susceptible-Exposed-Infectious-Removed structure that accounted for the clinical profile of SARS-COV-2 (asymptomatic, mild, severe and critical cases) and avenues of treatment access (outpatient, and hospitalisation in non-ICU and ICU wards). Between end-March and early September 2020, the model was updated 11 times with four key releases to generate new sets of projections and scenario analyses to be shared with planners in the national and provincial Departments of Health, the National Treasury and other partners. Updates to model structure included finer spatial granularity, limited access to treatment, and the inclusion of behavioural heterogeneity in relation to the adoption of Public Health and Social Measures. These updates were made in response to local data and knowledge and the changing needs of the planners. The NCEM attempted to incorporate a high level of local data to contextualise the model appropriately to address South Africa's population and health system characteristics that played a vital role in producing and updating estimates of resource needs, demonstrating the importance of harnessing and developing local modelling capacity.

Immigrants experience oral health care inequity: findings from Australia's National Study of Adult Oral Health

BACKGROUND

Oral health service utilization contributes to positive oral health and indicates realised access to services. The study aimed to describe patterns of oral health service use among overseas-born and Australian-born populations and assess equity in access to services.

METHODS

The study used data from Australia's National Study of Adult Oral Health 2017-2018 and was guided by the Aday and Andersen framework of access to health and Australia's National Oral Health Plan. Descriptive analyses of service use by perceived need, enabling and predisposing factors were compared between four groups: Australian-born and overseas-born who mainly speak English and Australian-born and overseas-born who mainly speak a language other than English.

RESULTS

Overseas-born who mainly speak a language other than English experienced greater oral health care inequity, largely driven by financial difficulty (avoided care due to cost: 42% vs 27%-28%; avoided/delayed visiting due to cost: 48% vs. 37%-38%; cost prevented treatment: 32% vs. 18%-24%). The most favourable visiting patterns were among the Australian-born population who speak a language other than English.

CONCLUSIONS

The study shows clear inequity experienced among immigrants in accessibility as measured through indicators of oral health care utilization and factors related to inequity, such as the ability to pay for services.

Dental enamel defects and dental caries of primary teeth among Indigenous children in Western Australia

BACKGROUND

Teeth affected with enamel defects (EDs) are at an increased risk of dental caries. In spite of improving oral health status overall in Australia, Indigenous Australians still experience higher rates of dental caries than non-Indigenous Australians. This study reports on the prevalence of EDs and dental caries experience among Indigenous children in the Kimberley region of Western Australia.

METHODS

Health status of all the primary teeth (ICDAS II criteria) and the presence of EDs on index teeth (modified Dental Defects of Enamel index; DDE) of young Indigenous children who participated in a 2-arm intervention trial was recorded. Generalized estimating equations were used to estimate the association between EDs and dental caries and effect estimates were presented as odds ratios and associated 95% confidence intervals.

RESULTS

Person-level prevalence, from 237 children (mean age 3.6 years, standard deviation 1.7) assessed for EDs, was 58% and tooth-level prevalence was 24%. Teeth affected with demarcated or diffuse defects were associated with a twofold higher odds of having caries experience, odds ratio (OR) 2.5, 95% confidence interval (CI) 1.7-3.7 and OR 2.7, 95% CI 1.7-4.0 respectively.

CONCLUSIONS

The presence of EDs among young Indigenous children was associated with a higher odds of caries experience among affected teeth.

Cost-effectiveness of voluntary medical male circumcision for HIV prevention across sub-Saharan Africa: results from five independent models

BACKGROUND

Voluntary medical male circumcision (VMMC) has been a recommended HIV prevention strategy in sub-Saharan Africa since 2007, particularly in countries with high HIV prevalence. However, given the scale-up of antiretroviral therapy programmes, it is not clear whether VMMC still represents a cost-effective use of scarce HIV programme resources.

METHODS

Using five existing well described HIV mathematical models, we compared continuation of VMMC for 5 years in men aged 15 years and older to no further VMMC in South Africa, Malawi, and Zimbabwe and across a range of setting scenarios in sub-Saharan Africa. Outputs were based on a 50-year time horizon, VMMC cost was assumed to be US$90, and a cost-effectiveness threshold of US$500 was used.

FINDINGS

In South Africa and Malawi, the continuation of VMMC for 5 years resulted in cost savings and health benefits (infections and disability-adjusted life-years averted) according to all models. Of the two models modelling Zimbabwe, the continuation of VMMC for 5 years resulted in cost savings and health benefits by one model but was not as cost-effective according to the other model. Continuation of VMMC was cost-effective in 68% of setting scenarios across sub-Saharan Africa. VMMC was more likely to be cost-effective in modelled settings with higher HIV incidence; VMMC was cost-effective in 62% of settings with HIV incidence of less than 0·1 per 100 person-years in men aged 15-49 years, increasing to 95% with HIV incidence greater than 1·0 per 100 person-years.

INTERPRETATION

VMMC remains a cost-effective, often cost-saving, prevention intervention in sub-Saharan Africa for at least the next 5 years.

FUNDING

Bill & Melinda Gates Foundation for the HIV Modelling Consortium.

Differential in-hospital mortality and intensive care treatment over time: Informing hospital pathways for modelling COVID-19 in South Africa

There are limited published data within sub-Saharan Africa describing hospital pathways of COVID-19 patients hospitalized. These data are crucial for the parameterisation of epidemiological and cost models, and for planning purposes for the region. We evaluated COVID-19 hospital admissions from the South African national hospital surveillance system (DATCOV) during the first three COVID-19 waves between May 2020 and August 2021. We describe probabilities and admission into intensive care units (ICU), mechanical ventilation, death, and lengths of stay (LOS) in non-ICU and ICU care in public and private sectors. A log-binomial model was used to quantify mortality risk, ICU treatment and mechanical ventilation between time periods, adjusting for age, sex, comorbidity, health sector and province. There were 342,700 COVID-19-related hospital admissions during the study period. Risk of ICU admission was 16% lower during wave periods (adjusted risk ratio (aRR) 0.84 [0.82-0.86]) compared to between-wave periods. Mechanical ventilation was more likely during a wave overall (aRR 1.18 [1.13-1.23]), but patterns between waves were inconsistent, while mortality risk in non-ICU and ICU were 39% (aRR 1.39 [1.35-1.43]) and 31% (aRR 1.31 [1.27-1.36]) higher during a wave, compared to between-wave periods, respectively. If patients had had the same probability of death during waves vs between-wave periods, we estimated approximately 24% [19%-30%] of deaths (19,600 [15,200-24,000]) would not have occurred over the study period. LOS differed by age (older patients stayed longer), ward type (ICU stays were longer than non-ICU) and death/recovery outcome (time to death was shorter in non-ICU); however, LOS remained similar between time periods. Healthcare capacity constraints as inferred by wave period have a large impact on in-hospital mortality. It is crucial for modelling health systems strain and budgets to consider how input parameters related to hospitalisation change during and between waves, especially in settings with severely constrained resources.

Attrition from HIV treatment after enrollment in a differentiated service delivery model: A cohort analysis of routine care in Zambia

BACKGROUND

Many sub-Saharan Africa countries are scaling up differentiated service delivery (DSD) models for HIV treatment to increase access and remove barriers to care. We assessed factors associated with attrition after DSD model enrollment in Zambia, focusing on patient-level characteristics.

METHODS

We conducted a retrospective record review using electronic medical records (EMR) of adults (≥15 years) initiated on antiretroviral (ART) between 01 January 2018 and 30 November 2021. Attrition was defined as lost to follow-up (LTFU) or died by November 30, 2021. We categorized DSD models into eight groups: fast-track, adherence groups, community pick-up points, home ART delivery, extended facility hours, facility multi-month dispensing (MMD, 4-6-month ART dispensing), frequent refill care (facility 1-2 month dispensing), and conventional care (facility 3 month dispensing, reference group). We used Fine and Gray competing risk regression to assess patient-level factors associated with attrition, stratified by sex and rural/urban setting.

RESULTS

Of 547,281 eligible patients, 68% (n = 372,409) enrolled in DSD models, most commonly facility MMD (n = 306,430, 82%), frequent refill care (n = 47,142, 13%), and fast track (n = 14,433, 4%), with <2% enrolled in the other DSD groups. Retention was higher in nearly all DSD models for all dispensing intervals, compared to the reference group, except fast track for the ≤2 month dispensing group. Retention benefits were greatest for patients in the extended clinic hours group and least for fast track dispensing.

CONCLUSION

Although retention in HIV treatment differed by DSD type, dispensing interval, and patient characteristics, nearly all DSD models out-performed conventional care. Understanding the factors that influence the retention of patients in DSD models could provide an important step towards improving DSD implementation.

How soon should patients be eligible for differentiated service delivery models for antiretroviral treatment? Evidence from a retrospective cohort study in Zambia

OBJECTIVES

Patient attrition is high the first 6 months after antiretroviral therapy (ART) initiation. Patients with <6 months of ART are systematically excluded from most differentiated service delivery (DSD) models, which are intended to support retention. Despite DSD eligibility criteria requiring ≥6 months on ART, some patients enrol earlier. We compared loss to follow-up (LTFU) between patients enrolling in DSD models early with those enrolled according to guidelines, assessing whether the ART experience eligibility criterion is necessary.

DESIGN

Retrospective cohort study using routinely collected electronic medical record data.

SETTING

PARTICIPANTS: Adults (≥15 years) who initiated ART between 1 January 2019 and 31 December 2020.

OUTCOMES

LTFU (>30 days late for scheduled visit) at 18 months for 'early enrollers' (DSD enrolment after <6 months on ART) and 'established enrollers' (DSD enrolment after ≥6 months on ART). We used a log-binomial model to compare LTFU risk, adjusting for age, sex, location, ART refill interval and DSD model.

RESULTS

For 6340 early enrollers and 25 857 established enrollers, there were no differences in sex (61% female), age (median 37 years) or location (65% urban). ART refill intervals were longer for established versus early enrollers (72% vs 55% were given 4-6 months refills). LTFU at 18 months was 3% (192 of 6340) for early enrollers and 5% (24 646 of 25 857) for established enrollers. Early enrollers were 41% less likely to be LTFU than established patients (adjusted risk ratio 0.59, 95% CI 0.50 to 0.68).

CONCLUSIONS

Patients enrolled in DSD after <6 months of ART were more likely to be retained than patients established on ART prior to DSD enrolment. A limitation is that early enrollers may have been selected for DSD due to providers' and patients' expectations about future retention. Offering DSD models to ART patients soon after ART initiation may help address high attrition during the early treatment period.

TRIAL REGISTERATION NUMBER

NCT04158882.

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.

Developing and testing unconditional cash transfer strategies among young adults with first-episode psychosis in South Africa: a study protocol for a pilot randomised control trial (PRS-FEP trial)

INTRODUCTION

Access to mental health services is a challenge, especially for young people who are over-represented in the unemployment and poverty index in South Africa. Therefore, continuing care is a problem after hospital discharge for young people with first-episode psychosis (FEP) due to a lack of clinical engagement and follow-up, for which they need support, including financial, to improve their outcomes. This pilot randomised control trial (RCT) aims to assess the feasibility and acceptability of financial support, in the form of an unconditional cash transfer (UCT), among young patients with FEP to prevent relapse.

METHODS AND ANALYSIS

This study will use a 1:1 ratio two-arm open-label pilot RCT of 60 young participants (18-29 years) with FEP in remission, who will be recruited from specialised psychiatric facilities in KwaZulu-Natal Province, South Africa. This study will implement an UCT and assess its feasibility, acceptability and preliminary clinical outcomes (ie, medication adherence, relapse, quality of life, personal and social function). The follow-up time will be 3 months, the outcomes being measured at baseline, months 1 and 3. Descriptive and conventional content analysis will be done for quantitative and qualitative data, respectively.

ETHICS AND DISSEMINATION

The study obtained provisional approval from the Biomedical Research Ethics Committee at the University of KwaZulu-Natal(#BREC/00004117/2022). Also is registered on the South African National clinical trial registry (#DOH-27-092022-5894) and approved by the KwaZulu-Natal department of health (#NHRD Ref: KZ_2002209_033). The results from this investigation will be actively disseminated through peer-reviewed journal publications, conference presentations and stakeholder engagement.

TRIAL REGISTRATION NUMBER

DOH-27-092022-5894.

Relative cost-effectiveness of long-acting injectable cabotegravir versus oral pre-exposure prophylaxis in South Africa based on the HPTN 083 and HPTN 084 trials: a modelled economic evaluation and threshold analysis

BACKGROUND

Long-acting injectable cabotegravir, a drug taken every 2 months, has been shown to be more effective at preventing HIV infection than daily oral tenofovir disoproxil fumarate and emtricitabine, but its cost-effectiveness in a high-prevalence setting is not known. We aimed to estimate the incremental cost-effectiveness of long-acting injectable cabotegravir compared with tenofovir disoproxil fumarate and emtricitabine in South Africa, using methods standard to government planning, and to determine the threshold price at which long-acting injectable cabotegravir is as cost-effective as tenofovir disoproxil fumarate and emtricitabine.

METHODS

In this modelled economic evaluation and threshold analysis, we updated a deterministic model of the South African HIV epidemic with data from the HPTN 083 and HPTN 084 trials to evaluate the effect of tenofovir disoproxil fumarate and emtricitabine and long-acting injectable cabotegravir provision to heterosexual adolescents and young women and men aged 15-24 years, female sex workers, and men who have sex with men. We estimated the average intervention cost, in 2021 US$, using ingredients-based costing, and modelled the cost-effectiveness of two coverage scenarios (medium or high, assuming higher uptake of long-acting injectable cabotegravir than tenofovir disoproxil fumarate and emtricitabine throughout) and, for long-acting injectable cabotegravir, two duration subscenarios (minimum: same pre-exposure prophylaxis duration as for tenofovir disoproxil fumarate and emtricitabine; maximum: longer duration than tenofovir disoproxil fumarate and emtricitabine) over 2022-41.

FINDINGS

Across long-acting injectable cabotegravir scenarios, 15-28% more new HIV infections were averted compared with the baseline scenario (current tenofovir disoproxil fumarate and emtricitabine roll-out). In scenarios with increased coverage with oral tenofovir disoproxil fumarate and emtricitabine, 4-8% more new HIV infections were averted compared with the baseline scenario. If long-acting injectable cabotegravir drug costs were equal to those of tenofovir disoproxil fumarate and emtricitabine for the same 2-month period, the incremental cost of long-acting injectable cabotegravir to the HIV programme was higher than that of tenofovir disoproxil fumarate and emtricitabine (5-10% vs 2-4%) due to higher assumed uptake of long-acting injectable cabotegravir. The cost per infection averted was $6053-6610 (tenofovir disoproxil fumarate and emtricitabine) and $4471-6785 (long-acting injectable cabotegravir). The cost per long-acting cabotegravir injection needed to be less than twice that of a 2-month supply of tenofovir disoproxil fumarate and emtricitabine to remain as cost-effective, with threshold prices ranging between $9·03 per injection (high coverage; maximum duration) and $14·47 per injection (medium coverage; minimum duration).

INTERPRETATION

Long-acting injectable cabotegravir could potentially substantially change HIV prevention. However, for its implementation to be financially feasible across low-income and middle-income countries with high HIV incidence, long-acting injectable cabotegravir must be reasonably priced.

FUNDING

United States Agency for International Development, The Bill & Melinda Gates Foundation.

Transmission reduction, health benefits, and upper-bound costs of interventions to improve retention on antiretroviral therapy: a combined analysis of three mathematical models

BACKGROUND

In this so-called treat-all era, antiretroviral therapy (ART) interruptions contribute to an increasing proportion of HIV infections and deaths. Many strategies to improve retention on ART cost more than standard of care. In this study, we aimed to estimate the upper-bound costs at which such interventions should be adopted.

METHODS

In this combined analysis, we compared the infections averted, disability-adjusted life-years (DALYs) averted, and upper-bound costs of interventions that improve ART retention in three HIV models with diverse structures, assumptions, and baseline settings: EMOD in South Africa, Optima in Malawi, and Synthesis in sub-Saharan African low-income and middle-income countries (LMICs). We modelled estimates over a 40-year time horizon, from a baseline of Jan 1, 2022, when interventions would be implemented, to Jan 1, 2062. We varied increment of ART retention (25%, 50%, 75%, and 100% retention), the extent to which interventions could be targeted towards individuals at risk of interrupting ART, and cost-effectiveness thresholds in each setting.

FINDINGS

Despite simulating different settings and epidemic trends, all three models produced consistent estimates of health benefit (ie, DALYs averted) and transmission reduction per increment in retention. The range of estimates was 1·35-3·55 DALYs and 0·12-0·20 infections averted over the 40-year time horizon per additional person-year retained on ART. Upper-bound costs varied by setting and intervention effectiveness. Improving retention by 25% among all people receiving ART, regardless of risk of ART interruption, gave an upper-bound cost per person-year of US$2-6 in Optima (Malawi), $43-68 in Synthesis (LMICs in sub-Saharan Africa), and $28-180 in EMOD (South Africa). A maximally targeted and effective retention intervention had an upper-bound cost per person-year of US$93-223 in Optima (Malawi), $871-1389 in Synthesis (LMICs in sub-Saharan Africa), and $1013-6518 in EMOD (South Africa).

INTERPRETATION

Upper-bound costs that could improve ART retention vary across sub-Saharan African settings and are likely to be similar to or higher than was estimated before the start of the treat-all era. Upper-bound costs could be increased by targeting interventions to those most at risk of interrupting ART.

FUNDING

Bill & Melinda Gates Foundation.

Inpatient Care Costs of COVID-19 in South Africa's Public Healthcare System

BACKGROUND

Coronavirus disease 2019 (COVID-19) has had a devastating impact globally, with severe health and economic consequences. To prepare health systems to deal with the pandemic, epidemiological and cost projection models are required to inform budgets and efficient allocation of resources. This study estimates daily inpatient care costs of COVID-19 in South Africa, an important input into cost projection and economic evaluation models.

METHODS

We adopted a micro-costing approach, which involved the identification, measurement and valuation of resources used in the clinical management of COVID-19. We considered only direct medical costs for an episode of hospitalisation from the South African public health system perspective. Resource quantities and unit costs were obtained from various sources. Inpatient costs per patient day was estimated for consumables, capital equipment and human resources for three levels of inpatient care - general wards, high care wards and intensive care units (ICUs).

RESULTS

Average daily costs per patient increased with the level of care. The highest average daily cost was estimated for ICU admissions - 271 USD to 306 USD (financial costs) and ~800 USD to 830 USD (economic costs, excluding facility fee) depending on the need for invasive vs. non-invasive ventilation (NIV). Conversely, the lowest cost was estimated for general ward-based care - 62 USD to 79 USD (financial costs) and 119 USD to 278 USD (economic costs, excluding facility fees) depending on the need for supplemental oxygen. In high care wards, total cost was estimated at 156 USD, financial costs and 277 USD, economic costs (excluding facility fees). Probabilistic sensitivity analyses suggest our costs estimates are robust to uncertainty in cost inputs.

CONCLUSION

Our estimates of inpatient costs are useful for informing budgeting and planning processes and cost-effectiveness analysis in the South African context. However, these estimates can be adapted to inform policy decisions in other context.

Cost-effectiveness of easy-access, risk-informed oral pre-exposure prophylaxis in HIV epidemics in sub-Saharan Africa: a modelling study

BACKGROUND

Approaches that allow easy access to pre-exposure prophylaxis (PrEP), such as over-the-counter provision at pharmacies, could facilitate risk-informed PrEP use and lead to lower HIV incidence, but their cost-effectiveness is unknown. We aimed to evaluate conditions under which risk-informed PrEP use is cost-effective.

METHODS

We applied a mathematical model of HIV transmission to simulate 3000 setting-scenarios reflecting a range of epidemiological characteristics of communities in sub-Saharan Africa. The prevalence of HIV viral load greater than 1000 copies per mL among all adults (HIV positive and negative) varied from 1·1% to 7·4% (90% range). We hypothesised that if PrEP was made easily available without restriction and with education regarding its use, women and men would use PrEP, with sufficient daily adherence, during so-called seasons of risk (ie, periods in which individuals are at risk of acquiring infection). We refer to this as risk-informed PrEP. For each setting-scenario, we considered the situation in mid-2021 and performed a pairwise comparison of the outcomes of two policies: immediate PrEP scale-up and then continuation for 50 years, and no PrEP. We estimated the relationship between epidemic and programme characteristics and cost-effectiveness of PrEP availability to all during seasons of risk. For our base-case analysis, we assumed a 3-monthly PrEP cost of US$29 (drug $11, HIV test $4, and $14 for additional costs necessary to facilitate education and access), a cost-effectiveness threshold of $500 per disability-adjusted life-year (DALY) averted, an annual discount rate of 3%, and a time horizon of 50 years. In sensitivity analyses, we considered a cost-effectiveness threshold of $100 per DALY averted, a discount rate of 7% per annum, the use of PrEP outside of seasons of risk, and reduced uptake of risk-informed PrEP.

FINDINGS

In the context of PrEP scale-up such that 66% (90% range across setting-scenarios 46-81) of HIV-negative people with at least one non-primary condomless sex partner take PrEP in any given period, resulting in 2·6% (0·9-6·0) of all HIV negative adults taking PrEP at any given time, risk-informed PrEP was predicted to reduce HIV incidence by 49% (23-78) over 50 years compared with no PrEP. PrEP was cost-effective in 71% of all setting-scenarios, and cost-effective in 76% of setting-scenarios with prevalence of HIV viral load greater than 1000 copies per mL among all adults higher than 2%. In sensitivity analyses with a $100 per DALY averted cost-effectiveness threshold, a 7% per year discount rate, or with PrEP use that was less well risk-informed than in our base case, PrEP was less likely to be cost-effective, but generally remained cost-effective if the prevalence of HIV viral load greater than 1000 copies per mL among all adults was higher than 3%. In sensitivity analyses based on additional setting-scenarios in which risk-informed PrEP was less extensively used, the HIV incidence reduction was smaller, but the cost-effectiveness of risk-informed PrEP was undiminished.

INTERPRETATION

Under the assumption that making PrEP easily accessible for all adults in sub-Saharan Africa in the context of community education leads to risk-informed use, PrEP is likely to be cost-effective in settings with prevalence of HIV viral load greater than 1000 copies per mL among all adults higher than 2%, suggesting the need for implementation of such approaches, with ongoing evaluation.

FUNDING

US Agency for International Development, US President's Emergency Plan for AIDS Relief, and Bill & Melinda Gates Foundation.

Cost and cost-effectiveness of dolutegravir-based antiretroviral regimens: an economic evaluation of a clinical trial

BACKGROUND

HIV programmes world-wide currently make decisions regarding new antiretroviral therapy (ART) regimens with less side-effects and higher resistance barriers, which may improve adherence and viral suppression. Economic evaluation helps inform these decisions.

METHODS

We conducted an economic evaluation of three ART regimens included in the ADVANCE trial from the provider's perspective: tenofovir alafenamide (TAF)/emtricitabine (FTC)+dolutegravir (DTG) and tenofovir disoproxil fumarate (TDF)/FTC+DTG, compared with TDF/FTC/efavirenz (EFV). We used top-down and bottom-up cost analysis with resource utilization based on trial data and adjusted to emulate routine care. We estimated the cost-effectiveness of each regimen as cost per person virally suppressed or retained and per life-year saved, at 48 and 96 weeks.

RESULTS

Though the DTG-based trial arms were 2% more costly than TDF/FTC/EFV, both had slightly lower cost-per-outcome ($9783 and $9929/patient virally suppressed for TDF/FTC+DTG and TAF/FTC+DTG, respectively) than TDF/FTC/EFV ($10 365). The trial cost per additional virally suppressed patient, compared with TDF/FTC/EFV, was lower in the TDF/FTC+DTG arm ($2967) compared with TAF/FTC+DTG ($3430). In routine care, cost per virally suppressed patient was estimated as similar between TDF/FTC+DTG ($426) and TDF/FTC/EFV ($424) but more costly under TAF/FTC+DTG. Similar results were seen in the cost per additional person retained across scenarios. When modelled over 20 years, TDF/FTC+DTG was more cost-effective than TAF/FTC+DTG ($10 341 vs $41 958/life-year saved).

CONCLUSION

TDF/FTC+DTG had similar costs per outcome as TDF/FTC/EFV in the routine care scenario but TDF/FTC+DTG was more cost-effective when modelled over 20 years.

The cost effectiveness and optimal configuration of HIV self-test distribution in South Africa: a model analysis

BACKGROUND

HIV self-testing (HIVST) has been shown to be acceptable, feasible and effective in increasing HIV testing uptake. Novel testing strategies are critical to achieving the UNAIDS target of 95% HIV-positive diagnosis by 2025 in South Africa and globally.

METHODS

We modelled the impact of six HIVST kit distribution modalities (community fixed-point, taxi ranks, workplace, partners of primary healthcare (PHC) antiretroviral therapy (ART) patients), partners of pregnant women, primary PHC distribution) in South Africa over 20 years (2020-2039), using data collected alongside the Self-Testing AfRica Initiative. We modelled two annual distribution scenarios: (A) 1 million HIVST kits (current) or (B) up to 6.7 million kits. Incremental economic costs (2019 US$) were estimated from the provider perspective; assumptions on uptake and screening positivity were based on surveys of a subset of kit recipients and modelled using the Thembisa model. Cost-effectiveness of each distribution modality compared with the status-quo distribution configuration was estimated as cost per life year saved (estimated from life years lost due to AIDS) and optimised using a fractional factorial design.

RESULTS

The largest impact resulted from secondary HIVST distribution to partners of ART patients at PHC (life years saved (LYS): 119 000 (scenario A); 393 000 (scenario B)). However, it was one of the least cost-effective modalities (A: $1394/LYS; B: $4162/LYS). Workplace distribution was cost-saving ($52-$76 million) and predicted to have a moderate epidemic impact (A: 40 000 LYS; B: 156 000 LYS). An optimised scale-up to 6.7 million tests would result in an almost threefold increase in LYS compared with a scale-up of status-quo distribution (216 000 vs 75 000 LYS).

CONCLUSION

Optimisation-informed distribution has the potential to vastly improve the impact of HIVST. Using this approach, HIVST can play a key role in improving the long-term health impact of investment in HIVST.

Role of data from cost and other economic analyses in healthcare decision-making for HIV, TB and sexual/reproductive health programmes in South Africa

An increasing focus on the use of the results of cost analyses and other economic evaluations in health programme decision-making by governments, donors and technical support partners working in low- and middle-income countries is accompanied by recognition that this use is impeded by several factors, including the lack of skills, data and coordination between spheres of the government. We describe our experience generating economic evaluation data for human immunodeficiency virus, tuberculosis and sexual/reproductive health programmes in South Africa alongside the results of a series of in-depth interviews (IDIs) among decision-makers within the South African government and implementing organizations (data users) and producers of economic evaluations (data producers). We summarize results across (1) the process of implementing a new intervention; (2) barriers to the use of cost data and suggested solutions and (3) the transferability of experiences to the planned South African implementation of universal health coverage (UHC). Based on our experience and the IDIs, we suggest concrete steps towards the improvement of economic data use in the planning and the establishment of structures mandated under the transition to UHC. Our key recommendations include the following: (1) compile a publicly available and regularly updated in-country cost repository; (2) increase the availability of programmatic outcomes data at the aggregate level; (3) agree upon and implement a set of primary decision criteria for the adoption and funding of interventions; (4) combine the efforts of health economics institutions into a stringent system for health technology assessments and (5) improve the link between national and provincial planning and budgeting.

Racism and oral health inequities among Indigenous Australians

Racial discrimination, which can be structural, interpersonal and intrapersonal, has causal links with oral health morbidity (dental caries, periodontal disease) and mortality (tooth loss). Racism impacts on oral health in three main ways: (1) institutional racism creates differential access to oral health services; (2) cultural racism, which is structurally pervasive, results in poorer psychological and physiological wellbeing of those discriminated against and; (3) interpersonal racism undermines important dental health service provider-patient relationships. Indigenous Australians have experienced sustained racial discrimination since European colonisation in the 1780s. This includes Government policies of land and custom theft, assimilation, child removal and restrictions on Indigenous people's civil rights, residence, mobility and employment. Australia failed to enumerate Indigenous people in the Census until 1967, with the 'White Australia' policy only ending in 1973. In our paper we posit that all minority groups experience racial discrimination that impacts oral health, but that this is amplified among Indigenous groups in Australia because of ongoing legacies of colonialism, institutional racism and intergenerational trauma.

The Role of Remdesivir in South Africa: Preventing COVID-19 Deaths Through Increasing Intensive Care Unit Capacity

Countries such as South Africa have limited intensive care unit (ICU) capacity to handle the expected number of patients with COVID-19 requiring ICU care. Remdesivir can prevent deaths in countries such as South Africa by decreasing the number of days people spend in ICU, therefore freeing up ICU bed capacity.

Oral health changes among Indigenous and non-Indigenous Australians: findings from two national oral health surveys

BACKGROUND

Historically, Indigenous Australians experienced poorer oral health than non-Indigenous Australians. We aimed to ascertain if Indigenous Australian oral health improved relative to non-Indigenous oral health between the 2004-06 and 2017-18 National Surveys of Adult Oral Health (NSAOH).

METHODS

Both NSAOHs were population-based cross-sectional surveys of Australian adults aged 15 years or more. In both surveys, representative samples of adults were drawn through a three-stage, stratified sample design within metropolitan and regional areas in each state/territory. Frequencies of Indigenous and non-Indigenous self-reported and clinical oral health variables were ascertained, and differences were calculated between the 2004-06 and 2017-18 NSAOHs. Ninety-five per cent confidence intervals were calculated and weights were used to account for the complex sampling methodology of both surveys.

RESULTS

In 2004-06, 229 Indigenous and 13 882 non-Indigenous Australians provided self-report data, and 87 and 5418 of these had dental examinations, respectively. In 2017-18, 334 Indigenous and 15 392 non-Indigenous Australians provided self-report data, and 84 and 4937 of them had dental examinations respectively. Between the surveys, relative to their non-Indigenous counterparts, Indigenous Australians experienced greater levels of: inadequate dentition (4.2%), experience of toothache (4.8%), problem-based dental attendance (4.5%) and 1+ teeth decayed, missing or filled (4.4%).

CONCLUSIONS

The gap between poor self-reported and clinical oral health between Indigenous and non-Indigenous Australians was greater in the more recent survey.

Potential Impact and Cost-Effectiveness of Condomless-Sex-Concentrated PrEP in KwaZulu-Natal Accounting for Drug Resistance

INTRODUCTION

Oral preexposure prophylaxis (PrEP) in the form of tenofovir-disoproxil-fumarate/emtricitabine is being implemented in selected sites in South Africa. Addressing outstanding questions on PrEP cost-effectiveness can inform further implementation.

METHODS

We calibrated an individual-based model to KwaZulu-Natal to predict the impact and cost-effectiveness of PrEP, with use concentrated in periods of condomless sex, accounting for effects on drug resistance. We consider (1) PrEP availability for adolescent girls and young women aged 15-24 years and female sex workers, and (2) availability for everyone aged 15-64 years. Our primary analysis represents a level of PrEP use hypothesized to be attainable by future PrEP programs.

RESULTS

In the context of PrEP use in adults aged 15-64 years, there was a predicted 33% reduction in incidence and 36% reduction in women aged 15-24 years. PrEP was cost-effective, including in a range of sensitivity analyses, although with substantially reduced (cost) effectiveness under a policy of ART initiation with efavirenz- rather than dolutegravir-based regimens due to PrEP undermining ART effectiveness by increasing HIV drug resistance.

CONCLUSIONS

PrEP use concentrated during time periods of condomless sex has the potential to substantively impact HIV incidence and be cost-effective.

Cost-effectiveness of Remdesivir and Dexamethasone for COVID-19 Treatment in South Africa

BACKGROUND

Dexamethasone and remdesivir have the potential to reduce coronavirus disease 2019 (COVID)-related mortality or recovery time, but their cost-effectiveness in countries with limited intensive care resources is unknown.

METHODS

We projected intensive care unit (ICU) needs and capacity from August 2020 to January 2021 using the South African National COVID-19 Epi Model. We assessed the cost-effectiveness of (1) administration of dexamethasone to ventilated patients and remdesivir to nonventilated patients, (2) dexamethasone alone to both nonventilated and ventilated patients, (3) remdesivir to nonventilated patients only, and (4) dexamethasone to ventilated patients only, all relative to a scenario of standard care. We estimated costs from the health care system perspective in 2020 US dollars, deaths averted, and the incremental cost-effectiveness ratios of each scenario.

RESULTS

Remdesivir for nonventilated patients and dexamethasone for ventilated patients was estimated to result in 408 (uncertainty range, 229-1891) deaths averted (assuming no efficacy [uncertainty range, 0%-70%] of remdesivir) compared with standard care and to save $15 million. This result was driven by the efficacy of dexamethasone and the reduction of ICU-time required for patients treated with remdesivir. The scenario of dexamethasone alone for nonventilated and ventilated patients requires an additional $159 000 and averts 689 [uncertainty range, 330-1118] deaths, resulting in $231 per death averted, relative to standard care.

CONCLUSIONS

The use of remdesivir for nonventilated patients and dexamethasone for ventilated patients is likely to be cost-saving compared with standard care by reducing ICU days. Further efforts to improve recovery time with remdesivir and dexamethasone in ICUs could save lives and costs in South Africa.

Neoliberalism and Indigenous oral health inequalities: a global perspective

Neoliberalism is the dominant ideology underpinning the operation of many governments. Its tenets include policies of economic liberalization such as privatization, deregulation, free trade and reduced public expenditures on infrastructure and social services. Champions of neoliberalism claim that expansion of global trade has rescued millions from abject poverty and that direct foreign investment successfully transfers technology to developing economies. However, critics have urged governments to pay greater attention to how neoliberalism shapes population health. Indigenous populations experience inequalities in ways that are unique and distinct from the experiences of other marginalised groups. This is largely due to colonial influences that have resulted in sustained loss of lands, identity, languages and the control to live life in a traditional, cultural way that is meaningful. Oral health is simultaneously a reflection of material circumstances, structural inequities and access to health services. Indigenous populations carry a disproportionate burden of oral health inequalities at a global level. In this commentary, we contend that neoliberalism has overwhelmingly contributed to these inequities in three ways: (1) increased dominance of transnational corporations; (2) privatization of health and; (3) the neoliberal emphasis on personal responsibility.

Community-based delivery of HIV treatment in Zambia: costs and outcomes

OBJECTIVE

The aim is to determine the total annual cost per patient treated and total cost per patient retained on antiretroviral therapy in Zambia in conventional care in facilities and across community-based differentiated service delivery (DSD) models.

DESIGN

Economic evaluation was conducted using retrospective electronic record review.Twenty healthcare facilities (13 with DSD models and 7 as comparison sites) in six of Zambia's 10 provinces were considered.

METHODS

All individuals on antiretroviral therapy (ART) >18 years old at the study sites were enrolled in a DSD model or conventional care by site type, respectively, with at least 12 months of follow-up data. Accessing care through DSD models [community adherence groups (CAGs), urban adherence groups (UAGs), home ART delivery and care, and mobile ART services] or facility-based conventional care with 3-monthly visits. Total annual cost per patient treated and the annual cost per patient retained in care 12 months after model enrolment. Retention in care was defined as attending a clinic visit at 12 months ± 3 months.

RESULTS

The DSD models assessed cost more per patient/year than conventional care. Costs ranged from an annual $116 to $199 for the DSD models, compared with $100 for conventional care. CAGs and UAGs increased retention by 2 and 14%, respectively. All DSD models cost more per patient retained at 12 months than conventional care. The CAG had the lowest cost/patient retained for DSD models ($140-157).

CONCLUSIONS

Although they achieve equal or improved retention in care, out-of-facility models of ART were more expensive than conventional care.

Atraumatic Restorative Treatments in Australian Aboriginal Communities: A Cluster-randomized Trial

INTRODUCTION

The management of early childhood caries (ECC) is challenging.

OBJECTIVES

A model of care based on Atraumatic Restorative Treatment and the Hall Technique (ART-HT) to manage ECC was evaluated among remote Aboriginal communities in Australia.

METHODS

Aboriginal communities in the North-West of Western Australia were invited to participate and consenting communities were randomized into early or delayed intervention for the management of ECC. Children were examined at baseline and at the 11-mo follow-up. The early intervention group (test) was provided with the ART-based dental care at baseline while the delayed intervention group (control) was advised to seek care through the usual care options available within the community. At follow-up, both groups were examined by calibrated examiners, and were offered care using the ART-HT approach. Changes from baseline to follow-up in caries experience were tested using paired tests. Multivariate analysis after multiple imputation of missing data used generalised estimating equation (GEE) controlling for clustering within communities.

RESULTS

A total of 25 communities and 338 children (mean age = 3.6 y, SD 1.7) participated in the study (test = 177). At follow-up, 231 children were examined (68% retention, test = 125). At follow-up, children in the test group had more filled teeth (test filled teeth = 1.2, control filled teeth = 0.2, P < 0.001) and decreased levels of decayed teeth (mean test = 0.7 fewer teeth with decay, mean control = 1.0 more tooth with decay, P < 0.001). GEE analysis controlled for baseline caries experience, age, sex, and community water fluoride levels found increased rates of untreated decayed teeth (RR = 1.4, P = 0.02) and decreased rates of filled teeth (RR = 0.2, P < 0.001) at follow-up among the control group.

CONCLUSION

A model of care relying on the principles of minimally invasive atraumatic approaches enabled the delivery of effective dental services to young children (<6 y) in remote Aboriginal Australian communities resulting in increased levels of care and improved oral health.

KNOWLEDGE TRANSFER STATEMENT

This cluster-randomized trial tested a multi-component model of dental care to young children with ECC in remote Aboriginal communities in Australia. The intervention, based on the atraumatic approaches using minimally invasive techniques encompassing preventive care, Atraumatic Restorative Treatment and the Hall Technique (ART-HT), delivered more restorative care and reduced the incidence of caries. This model of care was more effective than available standard care and should be incorporated into mainstream service delivery programs.

Cost-effectiveness of remdesivir and dexamethasone for COVID-19 treatment in South Africa

Background South Africa recently experienced a first peak in COVID-19 cases and mortality. Dexamethasone and remdesivir both have the potential to reduce COVID-related mortality, but their cost-effectiveness in a resource-limited setting with scant intensive care resources is unknown. Methods We projected intensive care unit (ICU) needs and capacity from August 2020 to January 2021 using the South African National COVID-19 Epi Model. We assessed cost-effectiveness of 1) administration of dexamethasone to ventilated patients and remdesivir to non-ventilated patients, 2) dexamethasone alone to both non-ventilated and ventilated patients, 3) remdesivir to non-ventilated patients only, and 4) dexamethasone to ventilated patients only; all relative to a scenario of standard care. We estimated costs from the healthcare system perspective in 2020 USD, deaths averted, and the incremental cost effectiveness ratios of each scenario. Results Remdesivir for non-ventilated patients and dexamethasone for ventilated patients was estimated to result in 1,111 deaths averted (assuming a 0-30% efficacy of remdesivir) compared to standard care, and save $11.5 million. The result was driven by the efficacy of the drugs, and the reduction of ICU-time required for patients treated with remdesivir. The scenario of dexamethasone alone to ventilated and non-ventilated patients requires additional $159,000 and averts 1,146 deaths, resulting in $139 per death averted, relative to standard care. Conclusions The use of dexamethasone for ventilated and remdesivir for non-ventilated patients is likely to be cost-saving compared to standard care. Given the economic and health benefits of both drugs, efforts to ensure access to these medications is paramount.

Oral Health Inequalities among Indigenous and Non-Indigenous Children

INTRODUCTION

Our ability to address child oral health inequalities would be greatly facilitated by a more nuanced understanding of whether underlying disease experience or treatment opportunities account for a larger share of differences between social groups. This is particularly relevant in the context of population subgroups who are socially marginalized, such as Australia's Indigenous population. The decayed, missing, and filled (dmf) surfaces index is at once a reflection of dental caries experience (d) and its management (m and f).

OBJECTIVES

To 1) describe socioeconomic inequalities in dental caries experience and its management among Indigenous and non-Indigenous children and 2) compare these inequalities using absolute and relative measures.

METHODS

Data were from the Australian National Child Oral Health Study 2012-2014. Absolute and relative income inequalities were assessed for overall dmfs and its individual components (ds, ms, fs) using adjusted means and health disparity indices (Slope Index of Inequality [SII] and Relative Index of Inequality [RII]).

RESULTS

Mean dmfs among Indigenous children aged 5 to 10 y was 6.4 (95% confidence interval [CI], 5.4-7.4), ranging from 2.3 in the highest to 9.1 in the lowest income group. Mean dmfs among non-Indigenous children was 2.9 (95% CI, 2.8-3.1), ranging from 1.9 in the highest to 4.2 in the lowest income group. Age- and gender-adjusted social gradients for Indigenous children were evident across all dmfs components but were particularly notable for ds (SII = -4.6, RII = -1.7) and fs (SII = -3.2, RII = -1.5). The social gradients for non-Indigenous children were much lower in magnitude: ds (SII = -1.8, RII = -1.6) and fs (SII = -0.7, RII = -0.5).

CONCLUSION

Our findings suggest that socioeconomic disadvantage may translate into both higher disease experience and increased use of dental services for both Indigenous and non-Indigenous groups, with the social gradients being much more amplified among Indigenous children.

KNOWLEDGE TRANSFER STATEMENT

The findings of this study demonstrate the magnitude of disparities in dental caries among children by population groups in Australia. Our results suggest that the relationship between socioeconomic disadvantage and poor oral health is more deleterious among Indigenous than non-Indigenous children. Tackling upstream determinants of health might not only affect population patterns of health and disease but also mitigate the overwhelming racial inequalities in oral health between Indigenous and non-Indigenous Australians.

A Psychometric Network Analysis of OHIP-14 across Australian and Brazilian Populations

OBJECTIVES

The aim of this study was to assess the structural validity of the Oral Health Impact Profile-14 (OHIP-14) instrument in Indigenous and non-Indigenous populations from Australia and Brazil using a network analysis approach.

METHODS

Cross-sectional data collected using OHIP-14 were obtained for Indigenous and non-Indigenous populations from Australia and Brazil. Networks were estimated using the Gaussian graphical model. Items of the OHIP-14 instrument are represented as nodes and the partial correlations between items as edges. Dimensionality was assessed using exploratory graph analysis. Structural consistency and item stability were computed using a bootstrap sampling method. Standardized node strength across each dimension was also calculated.

RESULTS

Four dimensions were identified across all samples, although the item arrangement of most dimensions presented variation. Similarities with the theoretical domains of the instrument were found. Items from the conceptually derived OHIP-14 domains formed separated clusters or blended with other items in a single dimension. Most dimensions across all samples showed an acceptable structural consistency. Item stability revealed some discrepancies among items of dimensions of both Indigenous networks.

CONCLUSION

The psychometric network perspective adopted in this study provides validation of the OHIP-14 structure in Indigenous and non-Indigenous populations. The structural consistency and item stability analyses showed that both Indigenous networks present a higher number of cross-domain items and less defined boundaries between dimensions. These findings indicate that OHIP-14 does not measure attributes in the same extent among different cultures.

KNOWLEDGE TRANSFER STATEMENT

This study demonstrates a new analytical framework from which to conceptualize and interpret the construct oral health-related quality of life using the Oral Health Impact Profile (OHIP-14). Network graphs facilitate knowledge translation of findings to professionals with no expertise in psychometric methods. OHIP-14 is a valuable tool to oral health research and clinical practice. Differences in conceptions of health may influence the extent that the instrument measures oral health impacts. Consequently, dimension scores do not always provide appropriate measures and should be avoided in research reports and assessments of treatment outcomes.

Incidence Trends of Lip, Oral Cavity, and Pharyngeal Cancers: Global Burden of Disease 1990–2017

The worldwide incidence trends of the lip, oral cavity, and pharyngeal cancers (LOCPs) need to be updated. This study aims to examine the temporal incidence trends of LOCPs from 1990 to 2017, using the latest Global Burden of Disease (GBD) study data to explore sex, age, and regional differences. GBD incidence data for LOCPs were driven by population cancer registries and were estimated from mortality data. Age-standardized incidence rates (ASIRs) were directly extracted from the 2017 GBD database to calculate the estimated annual percentage change (EAPC) over the study period. Incidence trends are mapped and compared separately by sex (females vs. males), age groups (15–49, 50–69, and 70+ y), regions (21 geographical and 5 sociodemographic regions), and countries. Among 678,900 incident cases of LOCPs notified in 2017, more than half were lip and oral cavity cancers. From 1990 to 2017, the estimated global incidence for nasopharyngeal cancers decreased dramatically (EAPC = −1.52; 95% confidence interval [CI], –1.70 to −1.34), while the incidence for lip and oral cavity cancers (EAPC = 0.26; 95% CI, 0.16–0.37) and other pharyngeal cancers (EAPC = 0.62; 95% CI, 0.54–0.71) increased. Higher ASIRs were observed among males than females across all age groups. However, females had larger EAPC variation when compared to males. Population groups aged 15 to 49 y presented the lowest ASIRs, with larger values of EAPC than those aged 50 to 69 and 70+ y. While high-income countries had higher ASIRs with little EAPC variation, ASIRs varied across low/middle-income regions with larger EAPC variations. South Asia and East Asia had the highest ASIRs and EAPC for lip and oral cavity cancers, respectively. In conclusion, the global incidence of LOCPs has increased among females, those aged 15 to 49 y, and people from low/middle-income countries over the study period, excepting nasopharyngeal cancers, which had a decreasing worldwide trend.

Data quality of drug-resistant tuberculosis and antiretroviral therapy electronic registers in South Africa

Background

To assess the quality and completeness of treatment and outcome data in the electronic tuberculosis (TB) and antiretroviral treatment (ART) registers in drug-resistant (DR-) TB patients at three treatment facilities in South Africa.

Methods

We did a retrospective cohort study using routinely-collected data from DR-TB registers of rifampicin resistant adults (≥18 years old), on ART, initiating DR-TB treatment between January 2012 and December 2013. We linked patient information from the DR-TB register to the ART register using patient identifiers and an algorithm based on string edit distance and date of birth. We describe data gaps and discrepancies found.

Results

Overall, 2852 DR-TB patients met our inclusion criteria based on the DR-TB register data, and of these, 1685 (59%) could be matched to the ART registers. An additional 253 patients from the DR-TB registers were found in the ART registers, having initiated ART, despite the DR-TB register indicating that they were not on ART (or this data was missing). 11% of matched patients did not have TB treatment status recorded in the ART register despite being recorded as being on TB treatment in the DR-TB register, and 78% did not have an ART start date recorded in DR-TB register despite being on ART treatment as per the ART register. 11% of matched patients had a death recorded in one register but not the other, and of those with death recorded in both, 15% of dates differed by > 1 month.

Conclusions

The underreporting of death and the lack of ART or TB status in the electronic DR-TB and ART registers could negatively impact monitoring efforts by downplaying the state of the TB/HIV epidemic. Improved recording of these data sources, and data integration across systems, could improve the accuracy of reporting for the national HIV/ART and TB programs.

Private Dental Care Benefits Non-Indigenous Children More Than Indigenous Children

INTRODUCTION

Various arrangements for funding health care facilities can have different levels of performance of care provision on different groups of people. Such differential performance of oral care is not previously known concerning Indigenous communities.

OBJECTIVE

This study aimed to assess the effect of visiting a public or private dental care facility on the performance of oral care experienced by Indigenous versus non-Indigenous children in Australia.

METHODS

Data from the National Child Oral Health Survey were used with a representative sample of children from all the states and territories of Australia. The performance of oral care was measured with the Child Oral Care Performance Assessment Scale (COPAS), which contains 37 items from 9 domains (Effective, Appropriate, Efficient, Responsive, Accessible, Safe, Continuous, Capable, and Sustainable) with a score ranging from 0 to 148. Mixed effects models that accounted for stratum and sampling weights were used for the stratified analyses (Indigenous vs. non-Indigenous) that assessed the effect of public versus private care on the COPAS. Relative excess risk due to interaction was calculated to assess effect modification.

RESULTS

Among the Indigenous children, private care was similar to public care (regression coefficient [RC] = -1.27, 95% CI = -9.5 to 6.97), whereas private care was higher than public care among non-Indigenous children (RC = 4.60, 95% CI = 3.67 to 6.18). This trend was similar among the 9 domains of the COPAS as well, except for Effectiveness, which was similar for private and public facilities among non-Indigenous children (RC = -0.03, 95% CI = -0.29 to 0.23). Based on the continuous COPAS score, effect modification was 4.46 (95% CI = 0.11 to 8.82) on the additive scale and 1.06 (1.01, 1.13) on the multiplicative scale. The relative excess risk due to interaction reported an excess chance of 1.17 (95% CI = 0.01 to 0.33), which was consistent with the stratified analyses and effect modification measured with the continuous score.

CONCLUSION

Thus, this study found a higher performance of oral care in private care locations among non-Indigenous children versus Indigenous children.

KNOWLEDGE TRANSFER STATEMENT

The findings caution policy makers and other stakeholders that moving oral care from public to private care facilities can increase the inequity faced by Indigenous children in Australia.

Political economy, trade relations and health inequalities: lessons from general health

OBJECTIVES

This article argues that health outcomes, specifically nutrition related health outcomes, are socially determined, and can be linked to a wider political economy in which peoples' dietary consumption is structurally determined, evolving from political, economic and social forces. The article examines trade and investment agreements as regulatory vehicles that cultivate poor dietary consumption and inequalities in health outcomes between and within countries. How does this happen? The liberalization of trade and investment, and unfettered influence of powerful economic interests including transnational food and beverage companies has resulted in trade agreements that enable excess availability, affordability and acceptability of highly processed, nutrient poor foods worldwide, ultimately resulting in poor nutrition and consequently oral and other non-communicable diseases. These trade and nutrition policy tensions shine a spotlight on the challenges ahead for global health and development policies, including achievement of the Sustainable Development Goals.

The per-patient costs of HIV services in South Africa: Systematic review and application in the South African HIV Investment Case

Background

In economic analyses of HIV interventions, South Africa is often used as a case in point, due to the availability of good epidemiological and programme data and the global relevance of its epidemic. Few analyses however use locally relevant cost data. We reviewed available cost data as part of the South African HIV Investment Case, a modelling exercise to inform the optimal use of financial resources for the country’s HIV programme.

Methods

We systematically reviewed publication databases for published cost data covering a large range of HIV interventions and summarised relevant unit costs (cost per person receiving a service) for each. Where no data was found in the literature, we constructed unit costs either based on available information regarding ingredients and relevant public-sector prices, or based on expenditure records.

Results

Only 42 (5%) of 1,047 records included in our full-text review reported primary cost data on HIV interventions in South Africa, with 71% of included papers covering ART. Other papers detailed the costs of HCT, MMC, palliative and inpatient care; no papers were found on the costs of PrEP, social and behaviour change communication, and PMTCT. The results informed unit costs for 5 of 11 intervention categories included in the Investment Case, with the remainder costed based on ingredients (35%) and expenditure data (10%).

Conclusions

A large number of modelled economic analyses of HIV interventions in South Africa use as inputs the same, often outdated, cost analyses, without reference to additional literature review. More primary cost analyses of non-ART interventions are needed.

Prevalence, incidence, predictors, treatment, and control of hypertension among HIV-positive adults on antiretroviral treatment in public sector treatment programs in South Africa

BACKGROUND

One of the key risk factors for cardiovascular disease is hypertension. Hypertension, which leads to heart attacks and strokes, already affects one billion people worldwide, making it a global public health issue. Incidence and prevalence of the condition is on the rise in low- and middle-income countries, with the biggest increase in sub-Saharan Africa and South Africa at the forefront. We examined the prevalence, incidence, predictors, treatment, and control of hypertension among HIV-positive patients on ART in a large South African observational cohort.

METHODS

We conducted a prospective study of ART naïve adults initiating ART at a public sector HIV clinic in South Africa between April 2004-2017. Patients with diagnosed hypertension at ART initiation were excluded from the incidence analysis. Log-binomial regression was used to estimate predictors of hypertension at ART initiation, while competing risks regression was used to evaluate the relationship between predictors of incident hypertension, accounting for death as a competing risk.

RESULTS

Among 77,696 eligible patients, 22.0% had prevalent hypertension at ART initiation. Of the remaining patients with no hypertension at ART initiation, 8,125 incident hypertension cases were diagnosed over the period of follow-up, corresponding to an incident rate of 5.4 per 100 person-years (95% confidence interval (CI): 5.3-5.6). We found patients ≥40 years of age and patients with a body mass index (BMI) ≥25kg/m2 were at increased risk of both prevalent and incident hypertension. Male patients and those with pre-hypertension at ART initiation had increased hazards of hypertension over the period of follow-up. When assessing the choice of antiretroviral drug in first-line ART, patients initiated on nevirapine were at 27% increased risk of developing hypertension compared to those initiated on efavirenz, while patients who initiated on either zidovudine or stavudine had a 40% increased risk of developing hypertension compared to patients initiated on tenofovir. Patientswith poorer health status at ART initiation (i.e. WHO III/IV stage, low CD4 count, low hemoglobin levels and low BMI) had a decrease risk of prevalent hypertension. We found an inverse relationship in patients with a CD4 count <50 cells/mm3 at ART initiation who had a 25% increased risk of incident hypertension compared to those with a CD4 count ≥350 cells/mm3.

CONCLUSION

Over 20% of patients in our cohort had hypertension at ART initiation, and 13% of those with normal blood pressure at ART initiation developed hypertension while on ART. Older patients, males, those on nevirapine, zidovudine or stavudine, and those who are overweight/obese should be targeted for frequent blood pressure monitoring and the identification of other cardiovascular risk factors to encourage lifestyle modifications. Additionally, these groups should be offered pharmaceutical therapy to help prevent myocardial infarction, heart failure, stroke, and kidney disease. Further research is needed to determine the level of access and adherence to pharmaceutical treatment for hypertension in this population. Additionally, an HIV-negative comparison population is needed to assess the association of the HIV virus itself with hypertension.

Cost-Effectiveness of Cervical Cancer Screening in Women Living With HIV in South Africa: A Mathematical Modeling Study

BACKGROUND

Women with HIV face an increased risk of human papillomavirus (HPV) acquisition and persistence, cervical intraepithelial neoplasia, and invasive cervical cancer. Our objective was to determine the cost-effectiveness of different cervical cancer screening strategies among women with HIV in South Africa.

METHODS

We modified a mathematical model of HPV infection and cervical disease to reflect coinfection with HIV. The model was calibrated to epidemiologic data from HIV-infected women in South Africa. Clinical and economic data were drawn from in-country data sources. The model was used to project reductions in the lifetime risk of cervical cancer and incremental cost-effectiveness ratios (ICERs) of Pap and HPV DNA screening and management algorithms beginning at HIV diagnosis, at 1-, 2-, or 3-year intervals. Strategies with an ICER below South Africa's 2016 per capita gross domestic product (US$5270) were considered "cost-effective."

RESULTS

HPV testing followed by treatment (test-and-treat) at 2-year intervals was the most effective strategy that was also cost-effective, reducing lifetime cancer risk by 56.6% with an ICER of US$3010 per year of life saved. Other cost-effective strategies included Pap (referral threshold: HSIL+) at 1-, 2-, and 3-year intervals, and HPV test-and-treat at 3-year intervals. Pap (ASCUS+), HPV testing with 16/18 genotyping, and HPV testing with Pap or visual triage of HPV-positive women were less effective and more costly than alternatives.

CONCLUSIONS

Considering per capita gross domestic product as the benchmark for cost-effectiveness, HPV test-and-treat is optimal in South Africa. At lower cost-effectiveness benchmarks, Pap (HSIL+) would be optimal.

Implementation of Option B and a fixed-dose combination antiretroviral regimen for prevention of mother-to-child transmission of HIV in South Africa: A model of uptake and adherence to care

INTRODUCTION

Initiating and retaining pregnant women on antiretroviral therapy (ART) to prevent mother-to-child HIV transmission (PMTCT) remains a major challenge facing African HIV programs, particularly during the critical final months prior to delivery. In 2013, South Africa implemented its "Option B" PMTCT regimen (three-drug ART throughout pregnancy and breastfeeding, regardless of maternal CD4 count) and introduced once-daily fixed-dose combinations and lifelong ART. Currently, the uptake of Option B and its possible impact on adherence to PMTCT during the critical final months of pregnancy is unclear.

MATERIALS AND METHODS

We prospectively collected visit data from a cohort of adult, HIV-infected, pregnant women between July 2013-August 2014 to estimate three models of adherence to PMTCT during the final 16 weeks immediately preceding delivery. Adherence was defined according to possession of antiretroviral drugs, which was inferred from clinic visit records under varying assumptions in each model. We describe uptake of the PMTCT regimen, gestational age at initiation, and model possible scenarios of adherence through delivery after the implementation of Option B.

RESULTS

Among 138 women enrolled (median (IQR) age 28 years (24-32), median CD4 count 378 cells/mm3), median (IQR) gestational age at initiation was 22 weeks (16-26). Estimates of adherence during the final 16 weeks of pregnancy prior to delivery ranged from 75% (52-89%) under the best case scenario assumptions to 52% (30-75%) under the worst case scenario assumptions. Estimates of the proportion of women who would achieve 80% adherence to PMTCT were <50% across all models.

CONCLUSIONS

Despite the switch to Option B and once-daily dosing, South African women continue to initiate PMTCT late in pregnancy, and estimations of regimen adherence, as modelled using PMTCT visit attendance data, is poor, with <50% of women reaching 80% adherence during final months of pregnancy across all models. Further guideline changes and interventions are needed to achieve vertical transmission goals.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01710397 South African National Clinical Trials Register DOH-27-0213-4177.

Confirmatory factor analysis of the health literacy in dentistry scale (HeLD) in the Australian population

OBJECTIVE

To determine the psychometric properties of both the long- and short-form versions of the Health Literacy in Dentistry (HeLD) instrument in a large sample of the Australian adult population.

METHODS

Data were from a subset of the National Dental Telephone Interview Survey 2013. Both the long (HeLD-29) and short-form (HeLD-14) were utilised, each of which comprises items from 7 conceptual domains: access, understanding, support, utilization, economic barriers, receptivity and communication. Confirmatory Factor Analysis was performed through structural equation modelling to determine factorial validity, where the Χ²/df, comparative fit, goodness of fit and root mean square error of approximation were used as indices of goodness of fit. Convergent validity was estimated from the average variance extracted (AVE) and composite reliability (CR), while internal consistency was estimated by Cronbach standardized alpha.

RESULTS

The dataset comprised 2,936 Australian adults aged 18+ years. The kurtosis and skewness values indicated an approximation to a normal distribution. Adequate fit was demonstrated for HeLD-14, but not for HeLD-29. Estimates of ≥ 0.50 for AVE and ≥ 0.70 for CR were demonstrated across all factors for both HeLD-29 and HeLD-14, indicating acceptable convergent validity for both forms. Discriminant validity was also demonstrated for both forms. Internal consistency was adequate in the seven conceptual domains for both HeLD forms, with Cronbach's alpha for all subscales being ≥0.70.

CONCLUSIONS

The psychometric properties of the HeLD instrument in a large sample of the Australian adult population were confirmed. The short form HeLD-14 was more parsimonious than the long-form (HeLD-29).

Reducing Indigenous Oral Health Inequalities: A Review from 5 Nations

Indigenous populations around the world experience a disproportionate burden in terms of oral diseases and conditions. These inequalities are likely due to a complex web of social determinants that includes poverty, historical consequences of colonialism, social exclusion, government policies of assimilation, cultural annihilation, and racism in all its forms (societal, institutional). Despite documented oral health disparities, prevention interventions have been scarce in Indigenous communities. This review describes oral health interventions and their outcomes conducted for Indigenous populations of the United States, Canada, Brazil, Australia, and New Zealand. The review includes research published since 2006 that are available in English in electronic databases, including MEDLINE. A total of 13 studies were included from the United States, Canada, Brazil, and Australia. The studies reviewed provide a wide range of initiatives, including interventions for prevention and treatment of dental disease, as well as interventions that improve oral health knowledge, behaviors, and other psychosocial factors. Overall, 6 studies resulted in improved oral health in the study participants, including improvements in periodontal health, caries reduction, and oral health literacy. Preferred intervention methodologies included community-based research approaches, culturally tailored strategies, and use of community workers to deliver the initiative. Although these studies were conducted with discrete Indigenous populations, investigators reported similar challenges in research implementation. Recommendations for future work in reducing oral health disparities include addressing social determinants of health in various Indigenous populations, training future generations of dental providers in cultural competency, and making Indigenous communities true partners in research.

The relationship between maternal smoking during pregnancy and parental-reported experience of dental caries in Indigenous Australian children

Objective

This study aimed to test the association between maternal smoking during pregnancy and parental-reported experience of dental caries in Indigenous Australian children.

Methods

Data were from the Longitudinal Study of Indigenous Children (LSIC); a population-based cohort study in Australia. Participants were 1,687 Indigenous Australian children aged 5 or less. Biological, social and behavioural variables were tested using log-linear modelling with binomial regression to determine the association with parental-reported experience of dental caries. Markov Chain Monte Carlo methods were used for multiple imputation of missing data.

Results

Overall 25.8% of Indigenous Australian children had dental caries as reported by a carer. In the multivariable model, increased prevalence of parental-reported caries was significantly associated with low maternal education levels (RR=1.60, 95%CI 1.17,2.20) and high sugar consumption (RR= 1.60, 95%CI 1.26,2.02). In the group of children whose mothers smoked tobacco during pregnancy, the association with parent-reported dental caries approached the threshold of significance, but was not significantly associated with caries status in children (RR=1.19, 95%CI 0.99,1.43). After multiple imputation, the most significant association was evident in children of the least educated mothers (RR=1.57, 95%CI 1.25,1.95), breastfeeding more than 12 months (RR=1.26, 95%CI 1.01,1.56), sweet intake more than 30% (RR=1.42, 95%CI 1.15,1.74) and 20-30% (RR=1.29 95%CI 1.04,1.59) and residing in outer regional (RR=1.56, 95%CI 1.19,2.05) or inner regional locations (RR=1.50, 95%CI 1.19,1.88). Mothers' tobacco smoking status showed a weak association with parent-reported dental decay (RR=1.42, 95%CI 1.20,1.68).

Conclusion

This study suggests there is a weak association between maternal smoking during pregnancy and prevalence of parentally-reported dental caries in Indigenous Australian children.

Revealed willingness-to-pay versus standard cost-effectiveness thresholds: Evidence from the South African HIV Investment Case

BACKGROUND

The use of cost-effectiveness thresholds based on a country's income per capita has been criticized for not being relevant to decision making, in particular in middle-income countries such as South Africa. The recent South African HIV Investment Case produced an alternative cost-effectiveness threshold for HIV prevention and treatment interventions based on estimates of life years saved and the country's committed HIV budget.

METHODS

We analysed the optimal mix of HIV interventions over a baseline of the current HIV programme under the committed HIV budget for 2016-2018. We calculated the incremental cost-effectiveness ratio (ICER) as cost per life-year saved (LYS) of 16 HIV prevention and treatment interventions over 20 years (2016-2035). We iteratively evaluated the most cost effective option (defined by an intervention and its coverage) over a rolling baseline to which the more cost effective options had already been added, thereby allowing for diminishing marginal returns to interventions. We constrained the list of interventions to those whose combined cost was affordable under the current HIV budget. Costs are presented from the government perspective, unadjusted for inflation and undiscounted, in 2016 USD.

RESULTS

The current HIV budget of about $1.6 billion per year was sufficient to pay for the expansion of condom availability, medical male circumcision, universal treatment, and infant testing at 6 weeks to maximum coverage levels, while also implementing a social and behavior change mass media campaign with a message geared at increasing testing uptake and reducing the number of sexual partners. The combined ICER of this package of services was $547/ LYS. The ICER of the next intervention that was above the affordability threshold was $872/LYS.

CONCLUSIONS

The results of the South African HIV Investment Case point to an HIV cost-effectiveness threshold based on affordability under the current budget of $547-872 per life year saved, a small fraction of the country's GDP per capita of about $6,000.

Cesarean birth is not associated with early childhood body mass index

Cesarean birth leads to a markedly different microbiome compared to vaginal birth, and the microbiome has been implicated in childhood obesity. Among mothers who had a previous cesarean, we compared anthropometry of 3- to 6-year-old children who were subsequently born by cesarean section versus vaginal birth. This large population-based study involved linking de-identified administrative perinatal and anthropometric data. Children's weight and height were collected at community-based clinics and converted to age- and sex-adjusted z-scores of height-for-age (HFAz), weight-for-age (WFAz) and BMI-for-age (BMIz). The average treatment effect (ATE) of cesarean versus vaginal birth was calculated from augmented inverse probability weighted analyses accounting for a wide range of confounding variables. There was little evidence of an effect of cesarean birth on HFAz (ATE = 0.26 95%CI -0.35, 0.87, n = 3993), WFAz (ATE = 0.35, 95%CI -0.19, 0.89, n = 4817) or BMIz (ATE = 0.11, 95%CI -0.25, 0.46, n = 3909). Cesarean section was not associated with anthropometry among children aged 3-6 years.