Limitations of the UNAIDS 90-90-90 metrics: a simulation-based comparison of cross-sectional and longitudinal metrics for the HIV care continuum

HIV epidemiology, prevention, treatment, and implementation strategies for public health

The global HIV response has made tremendous progress but is entering a new phase with additional challenges. Scientific innovations have led to multiple safe, effective, and durable options for treatment and prevention, and long-acting formulations for 2-monthly and 6-monthly dosing are becoming available with even longer dosing intervals possible on the horizon. The scientific agenda for HIV cure and remission strategies is moving forward but faces uncertain thresholds for success and acceptability. Nonetheless, innovations in prevention and treatment have often failed to reach large segments of the global population (eg, key and marginalised populations), and these major disparities in access and uptake at multiple levels have caused progress to fall short of their potential to affect public health. Moving forward, sharper epidemiologic tools based on longitudinal, person-centred data are needed to more accurately characterise remaining gaps and guide continued progress against the HIV epidemic. We should also increase prioritisation of strategies that address socio-behavioural challenges and can lead to effective and equitable implementation of existing interventions with high levels of quality that better match individual needs. We review HIV epidemiologic trends; advances in HIV prevention, treatment, and care delivery; and discuss emerging challenges for ending the HIV epidemic over the next decade that are relevant for general practitioners and others involved in HIV care.

Health systems performance for hypertension control using a cascade of care approach in South Africa, 2011-2017

Hypertension is a major contributor to global morbidity and mortality. In South Africa, the government has employed a whole systems approach to address the growing burden of non-communicable diseases. We used a novel incident care cascade approach to measure changes in the South African health system's ability to manage hypertension between 2011 and 2017. We used data from Waves 1-5 of the National Income Dynamics Study (NIDS) to estimate trends in the hypertension care cascade and unmet treatment need across four successive cohorts with incident hypertension. We used a negative binomial regression to identify factors that may predict higher rates of hypertension control, controlling for socio-demographic and healthcare factors. In 2011, 19.6% (95%CI 14.2, 26.2) of individuals with incident hypertension were diagnosed, 15.4% (95%CI 10.8, 21.4) were on treatment and 7.1% had controlled blood pressure. By 2017, the proportion of individuals with diagnosed incident hypertension had increased to 24.4% (95%CI 15.9, 35.4). Increases in treatment (23.3%, 95%CI 15.0, 34.3) and control (22.1%, 95%CI 14.1, 33.0) were also observed, translating to a decrease in unmet need for hypertension care from 92.9% in 2011 to 77.9% in 2017. Multivariable regression showed that participants with incident hypertension in 2017 were 3.01 (95%CI 1.77, 5.13) times more likely to have a controlled blood pressure compared to those in 2011. Our data show that while substantial improvements in the hypertension care cascade occurred between 2011 and 2017, a large burden of unmet need remains. The greatest losses in the incident hypertension care cascades came before diagnosis. Nevertheless, whole system programming will be needed to sufficiently address significant morbidity and mortality related to having an elevated blood pressure.

Alcohol use and the longitudinal HIV care continuum for people with HIV who enrolled in care between 2011 and 2019

PURPOSE

We described the impact of alcohol use on longitudinal engagement in HIV care including loss to follow-up, durability of viral suppression, and death.

METHODS

We followed a cohort of 1781 people with HIV from enrolled in care at one of seven US clinics, 2011-2019 through 102 months. We used a multistate, time-varying Markov process and restricted mean time to summarize engagement in HIV care over follow-up according to baseline self-reported alcohol use (none, moderate, or unhealthy).

RESULTS

Our sample (86% male, 54% White) had median age of 35 years. Over 102 months, people with no, moderate, and unhealthy alcohol use averaged 62.3, 61.1, and 59.5 months virally suppressed, respectively. People who reported unhealthy or moderate alcohol use spent 5.1 (95% confidence intervals (CI): 0.8, 9.3) and 7.6 (95%CI: 3.1, 11.7) more months lost to care than nondrinkers. Compared to no use, unhealthy alcohol use was associated with 3.4 (95%CI: -5.6, -1.6) fewer months in care, not virally suppressed. There were no statistically significant differences after adjustment for demographic and clinical characteristics.

CONCLUSIONS

Moderate or unhealthy drinking at enrollment in HIV care was associated with poor retention in care. Alcohol use was not associated with time spent virally suppressed.

Achieving the UNAIDS 90-90-90 targets: a comparative analysis of four large community randomised trials delivering universal testing and treatment to reduce HIV transmission in sub-Saharan Africa

BACKGROUND

Four large community-randomized trials examining universal testing and treatment (UTT) to reduce HIV transmission were conducted between 2012-2018 in Botswana, Kenya, Uganda, Zambia and South Africa. In 2014, the UNAIDS 90-90-90 targets were adopted as a useful metric to monitor coverage. We systematically review the approaches used by the trials to measure intervention delivery, and estimate coverage against the 90-90-90 targets. We aim to provide in-depth understanding of the background contexts and complexities that affect estimation of population-level coverage related to the 90-90-90 targets.

METHODS

Estimates were based predominantly on "process" data obtained during delivery of the interventions which included a combination of home-based and community-based services. Cascade coverage data included routine electronic health records, self-reported data, survey data, and active ascertainment of HIV viral load measurements in the field.

RESULTS

The estimated total adult populations of trial intervention communities included in this study ranged from 4,290 (TasP) to 142,250 (Zambian PopART Arm-B). The estimated total numbers of PLHIV ranged from 1,283 (TasP) to 20,541 (Zambian PopART Arm-B). By the end of intervention delivery, the first-90 target (knowledge of HIV status among all PLHIV) was met by all the trials (89.2%-94.0%). Three of the four trials also achieved the second- and third-90 targets, and viral suppression in BCPP and SEARCH exceeded the UNAIDS target of 73%, while viral suppression in the Zambian PopART Arm-A and B communities was within a small margin (~ 3%) of the target.

CONCLUSIONS

All four UTT trials aimed to implement wide-scale testing and treatment for HIV prevention at population level and showed substantial increases in testing and treatment for HIV in the intervention communities. This study has not uncovered any one estimation approach which is superior, rather that several approaches are available and researchers or policy makers seeking to measure coverage should reflect on background contexts and complexities that affect estimation of population-level coverage in their specific settings. All four trials surpassed UNAIDS targets for universal testing in their intervention communities ahead of the 2020 milestone. All but one of the trials also achieved the 90-90 targets for treatment and viral suppression. UTT is a realistic option to achieve 95-95-95 by 2030 and fast-track the end of the HIV epidemic.

A two-day workshop reviewing Canadian provincial and national HIV care cascade indicators, reporting, challenges, and recommendations

BACKGROUND

The HIV care cascade is an indicators-framework used to assess achievement of HIV clinical targets including HIV diagnosis, HIV care initiation and retention, initiation of antiretroviral therapy, and attainment of viral suppression for people living with HIV.

METHODS

The HIV Care Cascade Research Development Team at the CIHR Canadian HIV Trials Network Clinical Care and Management Core hosted a two-day virtual workshop to present HIV care cascade data collected nationally from local and provincial clinical settings and national cohort studies. The article summarizes the workshop presentations including the indicators used and available findings and presents the discussed challenges and recommendations.

RESULTS

Identified challenges included (1) inconsistent HIV care cascade indicator definitions, (2) variability between the use of nested UNAIDS's targets and HIV care cascade indicators, (3) variable analytic approaches based on differing data sources, (4) reporting difficulties in some regions due to a lack of integration across data platforms, (5) lack of robust data on the first stage of the care cascade at the sub-national level, and (6) inability to integrate key socio-demographic data to estimate population-specific care cascade shortfalls.

CONCLUSION

There were four recommendations: standardization of HIV care cascade indicators and analyses, additional funding for HIV care cascade data collection, database maintenance and analyses at all levels, qualitative interviews and case studies characterizing the stories behind the care cascade findings, and employing targeted positive-action programs to increase engagement of key populations in each HIV care cascade stage.

Global Health Facility-Based Interventions to Achieve UNAIDS 90-90-90: A Systematic Review and Narrative Analysis

To evaluate whether health facility-based HIV interventions align with UNAIDS 90-90-90 targets, we performed a systematic review through the lens of UNAIDS targets. We searched 11 databases, retrieving 5201 citations with 26 eligible studies classified by country income and UNAIDS target. We analyzed whether reporting of study outcome metrics was in line with UNAIDS targets using a standardized extraction form and results were summarized in a narrative synthesis given data heterogeneity. We also assessed the quality of randomized trials with the Cochrane Risk of Bias Tool and observational studies with the Newcastle-Ottawa Scale. Stratification of interventions by country income level revealed themes in successful interventions that provide insight for scale-up in similar resource contexts. Few studies reported outcomes using metrics according to UNAIDS targets. Standardization of reporting according to the UNAIDS framework could facilitate comparability of interventions and inform country-level progress on an international scale.

HIV continuum of care: bridging cross-sectional and longitudinal analyses

OBJECTIVE

The aim of this study was to propose a unified continuum-of-care (CoC) analysis combining cross-sectional and longitudinal elements, incorporating time spent between stages.

DESIGN

The established 90-90-90 target follows a cross-sectional four-stage CoC analysis, lacking information on timing of diagnosis, antiretroviral therapy (ART) initiation, and viral suppression durability.

METHODS

Data were derived from the Athens Multicenter AIDS Cohort Study (AMACS). In the cross-sectional CoC, we added stratification of diagnosed people with HIV (PWH) by estimated time from infection to diagnosis; of those who ever initiated ART or achieved viral suppression by corresponding current status (in 2018); and cumulative incidence function (CIF) of ART initiation and viral suppression, treating loss-to-follow-up (LTFU) as competing event. Viral suppression was defined as viral load less than 500 copies/ml. Viral suppression durability was assessed by the CIF of viral load rebound.

FINDINGS

About 89.1% of PWH in 2018 were diagnosed (range of diagnoses: 1980-2018). Median time to diagnosis was 3.5 years (IQR: 1.1-7.0). Among diagnosed, 89.1% were ever treated, of whom 86.7% remained on ART. CIF of ART initiation and LTFU before ART initiation were 80.9 and 6.0% at 5 years since diagnosis, respectively. Among treated, 89.4% achieved viral suppression, of whom 87.4% were currently virally suppressed. The CIF of viral load rebound was 24.2% at 5 years since first viral suppression but substantially reduced in more recent years.

INTERPRETATION

The proposed analysis highlights time gaps in CoC not evident by the standard cross-sectional approach. Our analysis highlights the need for early diagnosis and identifies late presenters as a key population for interventions that could decrease gaps in the CoC.

Global, regional, and national sex-specific burden and control of the HIV epidemic, 1990-2019, for 204 countries and territories: the Global Burden of Diseases Study 2019

BACKGROUND

The sustainable development goals (SDGs) aim to end HIV/AIDS as a public health threat by 2030. Understanding the current state of the HIV epidemic and its change over time is essential to this effort. This study assesses the current sex-specific HIV burden in 204 countries and territories and measures progress in the control of the epidemic.

METHODS

To estimate age-specific and sex-specific trends in 48 of 204 countries, we extended the Estimation and Projection Package Age-Sex Model to also implement the spectrum paediatric model. We used this model in cases where age and sex specific HIV-seroprevalence surveys and antenatal care-clinic sentinel surveillance data were available. For the remaining 156 of 204 locations, we developed a cohort-incidence bias adjustment to derive incidence as a function of cause-of-death data from vital registration systems. The incidence was input to a custom Spectrum model. To assess progress, we measured the percentage change in incident cases and deaths between 2010 and 2019 (threshold >75% decline), the ratio of incident cases to number of people living with HIV (incidence-to-prevalence ratio threshold <0·03), and the ratio of incident cases to deaths (incidence-to-mortality ratio threshold <1·0).

FINDINGS

In 2019, there were 36·8 million (95% uncertainty interval [UI] 35·1-38·9) people living with HIV worldwide. There were 0·84 males (95% UI 0·78-0·91) per female living with HIV in 2019, 0·99 male infections (0·91-1·10) for every female infection, and 1·02 male deaths (0·95-1·10) per female death. Global progress in incident cases and deaths between 2010 and 2019 was driven by sub-Saharan Africa (with a 28·52% decrease in incident cases, 95% UI 19·58-35·43, and a 39·66% decrease in deaths, 36·49-42·36). Elsewhere, the incidence remained stable or increased, whereas deaths generally decreased. In 2019, the global incidence-to-prevalence ratio was 0·05 (95% UI 0·05-0·06) and the global incidence-to-mortality ratio was 1·94 (1·76-2·12). No regions met suggested thresholds for progress.

INTERPRETATION

Sub-Saharan Africa had both the highest HIV burden and the greatest progress between 1990 and 2019. The number of incident cases and deaths in males and females approached parity in 2019, although there remained more females with HIV than males with HIV. Globally, the HIV epidemic is far from the UNAIDS benchmarks on progress metrics.

FUNDING

The Bill & Melinda Gates Foundation, the National Institute of Mental Health of the US National Institutes of Health (NIH), and the National Institute on Aging of the NIH.

HIV continuum of care: expanding scope beyond a cross-sectional view to include time analysis: a systematic review

INTRODUCTION

The continuum of care (CoC) model has been used to describe the main pillars of HIV care. This study aims to systematically review methods and elucidate gaps in the CoC analyses, especially in terms of the timing of the progression through steps, recognized nowadays as a critical parameter for an effective response to the epidemic.

METHODS

A PubMed and EMBASE databases search up to December 2019 resulted in 1918 articles, of which 209 were included in this review; 84 studies presented in major HIV conferences were also included. Studies that did not provide explicit definitions, modelling studies and those reporting only on metrics for subpopulations or factors affecting a CoC stage were excluded. Included articles reported results on 1 to 6 CoC stages.

RESULTS

Percentage treated and virally suppressed was reported in 78%, percentage diagnosed and retained in care in 58%, percentage linked to care in 54% and PLHIV in 36% of the articles. Information for all stages was provided in 23 studies. Only 6 articles use novel CoC estimates: One presents a dynamic CoC based on multistate analysis techniques, two base their time-to-next-stage estimates on a risk estimation method based on the cumulative incidence function, weighted for confounding and censoring and three studies estimated the HIV infection time based on mathematical modelling.

CONCLUSION

A limited number of studies provide elaborated time analyses of the CoC. Although time analyses lack the straightforward interpretation of the cross-sectional CoC, they provide valuable insights for the timely response to the HIV epidemic. A future goal would be to develop a model that retains the simplicity of the cross-sectional CoC but also incorporates timing between stages.

Improvements in transition times through the HIV cascade of care among gay and bisexual men with a new HIV diagnosis in New South Wales and Victoria, Australia (2012-19): a longitudinal cohort study

BACKGROUND

Most studies assessing the HIV care cascade have typically been cross-sectional analyses, which do not capture the transition time to subsequent stages. We aimed to assess the longitudinal HIV cascade of care in Australia, and changes over time in transition times and associated factors.

METHODS

In this longitudinal cohort study, we included linked data for gay and bisexual men (GBM) with a new HIV diagnosis who attended clinics participating in the Australian Collaboration for Coordinated Enhanced Sentinel Surveillance in New South Wales and Victoria between Jan 1, 2012, and Dec 31, 2019. We assessed three cascade transition periods: diagnosis to linkage to care (stage 1 transition); linkage to care to antiretroviral therapy (ART) initiation (stage 2 transition); and ART initiation to virological suppression (viral load ≤200 copies per mL; stage 3 transition). We also calculated the probability of remaining virologically suppressed after the first recorded viral load of less than 200 copies per mL. We used the Kaplan-Meier method to estimate transition times and cumulative probability of stage transition.

FINDINGS

We included 2196 GBM newly diagnosed with HIV between 2012 and 2019 contributing 6747 person-years of follow-up in our analysis. Median time from HIV diagnosis to linkage to care (stage 1 transition) was 2 days (IQR 1-3). Median time from linkage to care to ART initiation (stage 2 transition) was 33 days (30-35). Median time from ART initiation to first recorded virological suppression (stage 3 transition) was 49 days (47-52). The cumulative probability of ART initiation within 90 days of linkage to care increased from 36·9% (95% CI 32·9-40·6) in the 2012-13 calendar period to 94·1% (91·2-96·0) in the 2018-19 calendar period and cumulative probability of virological suppression within 90 days of ART initiation increased from 54·3% (48·8-59·3) in the 2012-13 calendar period to 82·9% (78·4-86·4) in the 2018-19 calendar period. 91·6% (90·1-93·1) of GBM remained virologically supressed up to 2 years after their first recorded virological suppression event.

INTERPRETATION

In countries with high cross-sectional cascade estimates such as Australia, the impact of treatment as prevention is better estimated using longitudinal cascade analyses.

FUNDING

National Health and Medical Research Council Australia.

Novel Longitudinal Methods for Assessing Retention in Care: a Synthetic Review

PURPOSE OF REVIEW

Retention in care is both dynamic and longitudinal in nature, but current approaches to retention often reduce these complex histories into cross-sectional metrics that obscure the nuanced experiences of patients receiving HIV care. In this review, we discuss contemporary approaches to assessing retention in care that captures its dynamic nature and the methodological and data considerations to do so.

RECENT FINDINGS

Enhancing retention measurements either through patient tracing or "big data" approaches (including probabilistic matching) to link databases from different sources can be used to assess longitudinal retention from the perspective of the patient when they transition in and out of care and access care at different facilities. Novel longitudinal analytic approaches such as multi-state and group-based trajectory analyses are designed specifically for assessing metrics that can change over time such as retention in care. Multi-state analyses capture the transitions individuals make in between different retention states over time and provide a comprehensive depiction of longitudinal population-level outcomes. Group-based trajectory analyses can identify patient subgroups that follow distinctive retention trajectories over time and highlight the heterogeneity of retention patterns across the population. Emerging approaches to longitudinally measure retention in care provide nuanced assessments that reveal unique insights into different care gaps at different time points over an individuals' treatment. These methods help meet the needs of the current scientific agenda for retention and reveal important opportunities for developing more tailored interventions that target the varied care challenges patients may face over the course of lifelong treatment.

Social Networks and HIV Care Outcomes in Rural Kenya and Uganda

BACKGROUND

Social isolation among HIV-positive persons might be an important barrier to care. Using data from the SEARCH Study in rural Kenya and Uganda, we constructed 32 community-wide, sociocentric networks and evaluated whether less socially connected HIV-positive persons were less likely to know their status, have initiated treatment, and be virally suppressed.

METHODS

Between 2013 and 2014, 168,720 adult residents in the SEARCH Study were census-enumerated, offered HIV testing, and asked to name social contacts. Social networks were constructed by matching named contacts to other residents. We characterized the resulting networks and estimated risk ratios (aRR) associated with poor HIV care outcomes, adjusting for sociodemographic factors and clustering by community with generalized estimating equations.

RESULTS

The sociocentric networks contained 170,028 residents (nodes) and 362,965 social connections (edges). Among 11,239 HIV-positive persons who named ≥1 contact, 30.9% were previously undiagnosed, 43.7% had not initiated treatment, and 49.4% had viral nonsuppression. Lower social connectedness, measured by the number of persons naming an HIV-positive individual as a contact (in-degree), was associated with poorer outcomes in Uganda, but not Kenya. Specifically, HIV-positive persons in the lowest connectedness tercile were less likely to be previously diagnosed (Uganda-West aRR: 0.89 [95% confidence interval (CI): 0.83, 0.96]; Uganda-East aRR: 0.85 [95% CI: 0.76, 0.96]); on treatment (Uganda-West aRR: 0.88 [95% CI: 0.80, 0.98]; Uganda-East aRR: 0.81 [0.72, 0.92]), and suppressed (Uganda-West aRR: 0.84 [95% CI: 0.73, 0.96]; Uganda-East aRR: 0.74 [95% CI: 0.58, 0.94]) than those in the highest connectedness tercile.

CONCLUSIONS

HIV-positive persons named as a contact by fewer people may be at higher risk for poor HIV care outcomes, suggesting opportunities for targeted interventions.