The effect of churn on "community viral load" in a well-defined regional population

Association between population viral load surrogate indicator and HIV transmission potential: a prospective cohort study in Xinjiang, China

BACKGROUND

New indicators of potential human immunodeficiency virus (HIV) transmission are being actively explored. We aim to categorical testing of the viral load (VL) of persons living with HIV (PLWH) in order to explore new indicators to measure the intensity of the epidemic and the effectiveness of the response in the community.

METHODS

A dynamic cohort study was conducted in Yining to monitor the VL of all persons living with HIV from 2017 to 2019. Different population VL (PVL) surrogate indicators were measured and the strength of the associations of different PVL surrogates with HIV incidence, antiretroviral therapy (ART) coverage, virus unsuppression, and viremia prevalence was assessed. PVL surrogate indicators were used to describe the current status of HIV transmission in different populations and communities.

RESULTS

All PVL indicators decreased from 2017 to 2019 (P < 0.05). Arithmetic mean community viral load (CVL) (r = 1.000, P = 0.006) and geometric mean CVL (r = 1.000, P = 0.001) were positively associated with HIV incidence, ART coverage and viral unsuppression (P < 0.05). CVL was higher in the male, ≤ 25 years of age, primary school or below, other household registration, other medical insurance types, other source of sample, nonmarital and noncommercial heterosexual contact, and nonmarital and commercial heterosexual contact subgroups. Community-based cross-sectional analyses showed that CVL in community 10 was positively correlated with viral unsuppression rate and viremia prevalence but negatively correlated with ART coverage rate, suggesting that the community was a hotspot for HIV epidemics.

CONCLUSIONS

CVL can be used as an indicator for assessing HIV transmission and identifying high-risk populations and hotspot communities.

Modeling the HIV Cascade of Care Using Routinely Collected Clinical Data to Guide Programmatic Interventions and Policy Decisions

BACKGROUND

The HIV care cascade is a framework to examine effectiveness of HIV programs and progress toward global targets to end the epidemic but has been conceptualized as a unidirectional process that ignores cyclical care patterns. We present a dynamic cascade that accounts for patient "churn" and apply novel analytic techniques to readily available clinical data to robustly estimate program outcomes and efficiently assess progress toward global targets.

METHODS

Data were assessed for 35,649 people living with HIV and receiving care at 78 clinics in East Africa between 2014 and 2020. Patients were aged ≥15 years and had ≥1 viral load measurements. We used multi-state models to estimate the probability of being in 1 of 5 states of a dynamic HIV cascade: (1) in HIV care but not on antiretroviral therapy (ART), (2) on ART, (3) virally suppressed, (4) in a gap-in-care, and (5) deceased and compared these among subgroups. To assess progress toward global targets, we summed those probabilities across patients and generated population-level proportions of patients on ART and virally suppressed in mid-2020.

RESULTS

One year after enrollment, 2.8% of patients had not initiated ART, 86.7% were receiving ART, 57.4% were virally suppressed, 10.2% were disengaged from care, and 0.3% had died. At 5 years, the proportion on ART remained steady but viral suppression increased to 77.2%. Of those aged 15-25, >20% had disengaged from care and <60% were virally suppressed. In mid-2020, 90.1% of the cohort was on ART, 90.7% of whom had suppressed virus.

CONCLUSIONS

Novel analytic approaches can characterize patient movement through a dynamic HIV cascade and, importantly, by capitalizing on readily available data from clinical cohorts, offer an efficient approach to estimate population-level proportions of patients on ART and virally suppressed. Significant progress toward global targets was observed in our cohort but challenges remain among younger patients.

The Impact of Churn on HIV Outcomes in a Southern United States Clinical Cohort

Background

Persons with human immunodeficiency virus (PWH) may experience a cycle of engaging and disengaging in care referred to as “churn.” While human immunodeficiency virus (HIV) churn is predicted to be more prevalent in the southern United States (US), it has not been well characterized in this region.

Methods

We conducted a retrospective cohort study involving PWH newly establishing care at a large urban clinic in Atlanta, Georgia, from 2012 to 2017, with follow-up data collected through 2019. The primary exposure was churn, defined as a ≥12-month gap between routine clinic visits or viral load (VL) measurements. We compared HIV metrics before and after churn and assessed the risk of future churn or loss to follow-up.

Results

Of 1303 PWH newly establishing care, 81.7% were male and 84.9% were Black; 200 (15.3%) experienced churn in 3.3 years of median follow-up time. The transmissible viremia (TV) rate increased from 28.6% prechurn to 66.2% postchurn (P < .0001). The 122 PWH having TV on reengagement had delayed time to subsequent viral suppression (adjusted hazard ratio, 0.59 [95% confidence interval {CI}, .48–.73]), and PWH returning to care contributed disproportionately to the community viral load (CVL) (proportion of CVL/proportion of patients, 1.96). Churn was not associated with an increased risk of subsequent churn (adjusted odds ratio [aOR], 1.53 [95% CI, .79–2.97]) or loss to follow-up (aOR, 1.04 [95% CI, .60–1.79]).

Conclusions

The rate of churn in a southern US clinic was high, and those who experienced churn had increased TV at reentry and disproportionately contributed to the CVL and likely contributing to ongoing HIV transmission.

Hepatitis C Virus (HCV) Care Continuum Outcomes and HCV Community Viral Loads Among Patients in an Opioid Treatment Program

BACKGROUND

Hepatitis C virus (HCV) remains endemic among people who use drugs (PWUD). Measures of HCV community viral load (CVL) and HCV care continuum outcomes may be valuable for ascertaining unmet treatment need and for HCV surveillance and control.

METHODS

Data from patients in an opioid treatment program during 2013-2016 were used to (1) identify proportions of antibody and viral load (VL) tested, linked-to-care, and treated, in 2013-2014 and 2015-2016, and pre- and postimplementation of qualitative reflex VL testing; (2) calculate engaged-in-care HCV CVL and "documented" and "estimated" unmet treatment need; and (3) examine factors associated with linkage-to-HCV-care.

RESULTS

Among 11 267 patients, proportions of HCV antibody tested (52.5% in 2013-2014 vs 73.3% in 2015-2016), linked-to-HCV-care (15.7% vs 51.8%), and treated (12.0% vs 44.7%) all increased significantly. Hispanic ethnicity was associated with less linkage-to-care, and Manhattan residence was associated with improved linkage-to-care. The overall engaged-in-care HCV CVL was 4 351 079 copies/mL (standard deviation = 7 149 888); local HCV CVLs varied by subgroup and geography. Documented and estimated unmet treatment need decreased but remained high.

CONCLUSIONS

After qualitative reflex VL testing was implemented, care continuum outcomes improved, but gaps remained. High rates of unmet treatment need suggest that control of the HCV epidemic among PWUD will require expansion of HCV treatment coverage.

Impact of three decades of antiretroviral therapy in a longitudinal population cohort study

BACKGROUND

We have used a comprehensive HIV population to characterize antiretroviral therapy (ART), drug class selection, pill burden, drug costs and health outcomes over the entire span of the HIV epidemic.

METHODS

Antiretroviral (ARV) use (drugs, classes, formulations) and both the laboratory and clinical outcomes (HIV-1 RNA, CD4⁺ T-cell count and mortality) were determined for all patients in Southern Alberta, Canada, at each year-end between 1986 and 2017. Pill burden, cumulative drug exposure and costs were calculated for each year.

RESULTS

The number of ARV-treated patients increased from 29.6% (77/260) in 1989 to 93.4% (1,814/1,943) in 2017. Regimen selection showed continuous adjustments for toxicity, resistance, pill burden and adherence. Dramatic improvements in outcomes were seen. In 1997, 22.4% of treated patients had an undetectable viral load, this has been consistently around 90% since 2010 (92.7% in 2017). While HIV-related annual mortality rate declined from 11.0% in 1994 to 0.1% in 2017, all-cause mortality remained relatively stable from 1997 onwards. ART pill burden escalated in 1997 (12.4/day), then decreased to 2.1/day in 2016. Mean ART cost increased in 1997 (CAN$905/month/regimen in 1997, $1,223 in 2016). Mean cumulative lifetime exposure to protease inhibitors is 5.98 ±4.9 and to nucleoside reverse transcriptase inhibitors 8.8 ±6.2 years.

CONCLUSIONS

Our findings demonstrate not only the immense burden that HIV has imposed on both patients and society, but also the substantial benefit of ART on patient outcomes. They show that research, patient engagement and programme support can with time minimize the harmful long-term effects of HIV-infection.

Loss to follow-up and opportunities for reengagement in HIV care in rural Mozambique: A prospective cohort study

Patients lost to follow-up (LTFU) over the human immunodeficiency virus (HIV) cascade have poor clinical outcomes and contribute to onward HIV transmission. We assessed true care outcomes and factors associated with successful reengagement in patients LTFU in southern Mozambique.Newly diagnosed HIV-positive adults were consecutively recruited in the Manhiça District. Patients LTFU within 12 months after HIV diagnosis were visited at home from June 2015 to July 2016 and interviewed for ascertainment of outcomes and reasons for LTFU. Factors associated with reengagement in care within 90 days after the home visit were analyzed by Cox proportional hazards model.Among 1122 newly HIV-diagnosed adults, 691 (61.6%) were identified as LTFU. Of those, 557 (80.6%) were approached at their homes and 321 (57.6%) found at home. Over 50% had died or migrated, 10% had been misclassified as LTFU, and 252 (78.5%) were interviewed. Following the visit, 79 (31.3%) reengaged in care. Having registered in care and a shorter time between LTFU and visit were associated with reengagement in multivariate analyses: adjusted hazards ratio of 3.54 [95% confidence interval (CI): 1.81-6.92; P < .001] and 0.93 (95% CI: 0.87-1.00; P = .045), respectively. The most frequently reported barriers were the lack of trust in the HIV-diagnosis, the perception of being in good health, and fear of being badly treated by health personnel and differed by type of LTFU.Estimates of LTFU in rural areas of sub-Saharan Africa are likely to be overestimated in the absence of active tracing strategies. Home visits are resource-intensive but useful strategies for reengagement for at least one-third of LTFU patients when applied in the context of differentiated care for those LTFU individuals who had already enrolled in HIV care at some point.

Validation of Retention in HIV Care Status Using the New York City HIV Surveillance Registry and Clinical Care Data From a Large HIV Care Center

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Context:

Improving retention in care is a key element of the National HIV/AIDS Strategy (NHAS). However, definitions for measuring retention in care are not standardized.

Objective:

To compare measures of retention based on both clinic visit data and HIV laboratory surveillance data.

Design:

Retrospective cohort study.

Setting:

New York City (NYC), New York.

Participants:

We matched adult patients with HIV infection seen at the Spencer Cox Center for Health (SCC) in 2010 or 2011 with the NYC HIV Surveillance Registry.

Main Outcome Measures:

Retention in care was measured on the basis of SCC electronic medical record (EMR) data (≥1 medical visits in 2012) and Surveillance Registry data (≥2 CD4/viral load [VL] tests ≥90 days apart in 2012).

Results:

There were 5746 adult HIV-infected patients seen at SCC between 2010 and 2011 who matched with the Surveillance Registry. Seventy-eight percent (n = 4469) had 1 or more medical visits at SCC in 2012 and were considered retained on the basis of the EMR definition, among which 3831 (86%) met the surveillance definition for retention in care. Patients who did not have a medical visit at SCC in 2012 (n = 1277) were lost to care in NYC (n = 485; 36%), engaged in care at an alternate provider (n = 622; 49%), or died after their last SCC visit (n = 197; 15%).

Implications:

This study is an important comparison of laboratory surveillance versus clinic visit-based measures of retention in care in an urban setting with the largest HIV epidemic in the country. Collaborative projects between local health departments and clinical care providers can help validate the care status of patients and inform the allocation of resources to reengage patients who are lost to care.

Conclusion:

The combined use of laboratory and clinic visit–based data to measure retention in care provides a more accurate representation of the care status of HIV-infected patients than use of a single data source alone. Routine sharing of data by public health institutions and clinical care providers would help target resources toward reengaging patients who are lost to care in jurisdictions with universal HIV-related laboratory reporting.

Reduction in HIV community viral loads following the implementation of a "Treatment as Prevention" strategy over 2 years at a population-level among men who have sex with men in Hangzhou, China

Background

Previous studies have shown that the increased coverage of antiretroviral therapy (ART) could reduce the community viral load (CVL) and reduce the occurrence of new HIV infections. However, the impact on the reduction of HIV transmission among men who have sex with men (MSM) is much less certain. The frequency of HIV infections in MSM have been rapidly increasing in recent years in Hangzhou, China. The “Treatment as Prevention” strategy was implemented at a population-level for HIV-infected MSM from January 2014 to June 2016 in Hangzhou; it aimed to increase the ART coverage, reduce the CVL, and reduce HIV transmission.

Methods

We investigated a subset of MSM diagnosed with HIV pre- and post-implementation of the strategy, using random sampling methods. Viral load (VL) testing was performed for all enrolled individuals; the lower limits of detection were 20 and 50 copies/mL. The data on infections were collected from the national epidemiology database of Hangzhou. Logistic regression analyses were conducted to identify factors associated with the differences in social demographic characteristics and available VL data.

Results

The ART coverage increased from 60.7% (839/1383) during the pre-implementation period to 92.3% (2183/2365) during the post-implementation period in Hangzhou. A total of 940 HIV-infected MSM were selected for inclusion in this study: 490 (52.1%) and 450 (47.9%) MSM in the pre- and post-implementation periods, respectively. In total, 89.5% (841/940) of patients had data available on VL rates. The mean CVL was 579 copies/mL pre-implementation and this decreased to 33 copies/mL post-implementation (Kruskal-Wallis < 0.001). The mean CVL decreased for all variables investigated post-implementation of the treatment strategy (P < 0.05). The undetectable VL (≤400 copies/mL) rate pre-implementation period was 50.0% which increased to 84.7% post-implementation (P < 0.001). The mean CVL at the county level significantly decreased in each county post-implementation (Kruskal-Wallis < 0.05).

Conclusion

Our study confirmed a population-level association between increased ART coverage and decreased mean CVL; overall 84.7% of HIV infected MSM had an undetectable VL and were no longer infectious.

Community viral load of HIV in Brazil, 2007 - 2011: potential impact of highly active antiretroviral therapy (HAART) in reducing new infections

Objectives:

To estimate the human immunodeficiency virus (HIV) viral load in the Brazilian population and to assess the potential impact of highly active antiretroviral therapy (HAART) in reducing new infections to build evidences and to gather information to support health policies.

Methods:

Spatial analysis and modeling tools were used to describe the existing patterns of the viral load density, using the Kernel method. Data on viral load and treatment were retrieved from the databases Laboratory Tests Control System (SISCEL), which contains information on the individual's history of viral load, and Medication Logistics Control System (SICLOM), which controls the dispensing of drugs used for antiretroviral therapy.

Results:

It was observed that the community viral load (CVL) decreased progressively from 2007 to 2011, accompanied by a decrease of more than 32% in the mean CVL (CVLM) - 22,900 copies/mL in 2007 versus 15,418 copies/mL in 2011. During this period, there was a reduction of CVLM in all regions of Brazil, although North and Northeast showed, respectively, CVLM 1.7 and 1.5 times higher than that in the Southeast region. A comparison between the individuals who underwent and who did not undergo HAART showed an increase of up to 3.9 times in 2011 in the viral load among those who did not undergo the therapy.

Conclusion:

The approach presented in this study indicates the existence of clusters with high concentrations. The use of Kernel in the identification of clusters proved to be a good tool for exploratory analysis, enabling the risk identification in certain geographic areas without the usual political and administrative divisions.

Comparing viral load metrics and evaluating their use for HIV surveillance

OBJECTIVES

To investigate the value of in-care viral load (ICVL) and other viral load (VL) metrics for HIV surveillance by comparing time trends and associations with numbers of new HIV diagnoses.

METHODS

Data from 20,740 HIV patients registered in the Dutch ATHENA-cohort between 2002 and 2013 were used. We compared: six ICVL metrics (i.e. mean of the mean/first/last/highest log VL, median of the median log VL, first log VL for newly diagnosed combined with mean log VL for all others), log VL at diagnosis, proportion of patients with transmission risk (>400 copies/ml) or suppressed VL (≤200 copies/ml). Subgroup differences were assessed using Kruskal-Wallis and chi-square tests. Negative binomial regression was used for studying associations between VL metrics and numbers of new diagnoses 1-4 years later.

RESULTS

Most ICVL metrics showed similar decreasing trends over time. Differences in covariables were found for all VL metrics. Mean ICVL showed the strongest association with new diagnoses: a decrease of one log unit in mean ICVL was associated with a 21% decrease in new diagnoses two years later.

CONCLUSIONS

VL metrics may be of value for enhancing HIV surveillance by identifying subgroup differences in impact of treatment on viral suppression, and by predicting numbers of new diagnoses in subsequent years.

An Exploratory Study to Assess Individual and Structural Level Barriers Associated With Poor Retention and Re-engagement in Care Among Persons Living With HIV/AIDS

BACKGROUND

Retention in care is the most challenging step along the HIV care continuum. Many patients who engage in care and achieve viral suppression have care interruptions, characterized by moving in and out of care ("churn"). Poor retention has clinical consequences and contributes to new HIV transmissions, but how to predict or prevent it remains elusive. This study sought to understand the relationship between individual- and structural-level barriers, and poor retention for persons living with HIV/AIDS in Atlanta, GA.

METHODS

We administered a survey, through interviews, with HIV-infected patients continuously retained in care for 6 years ("continuously retained," n = 32) and patients with recent gaps in care ("unretained" n = 27). We assessed individual-level protective factors for successful engagement (self-efficacy, resilience, perceived social support, and disclosure), risk factors for poor engagement (substance use, mental illness, and stigma), and structural/systemic-level barriers (financial and housing instability, transportation, food insecurity, communication barriers, and incarceration history). Chi-square and Mann-Whitney U tests were used to compare the 2 populations.

RESULTS

Both continuously retained and unretained populations had high rates of prior viral suppression but few unretained patients were virologically suppressed upon return to care (11%). Younger age, crack cocaine use, food insecurity, financial instability, housing instability, and phone number changes in the past year were significantly more likely to be present in the unretained population.

CONCLUSIONS

Our findings suggest the need for targeted risk assessment tools to predict the highest-risk patients for poor retention whereby public health interventions can be directed to those individuals.

Reduced community viral load does not coincide with a reduction in the rate of new HIV diagnoses and recent infections: data from a region of southern Italy

OBJECTIVES

We assessed whether changes in community viral load (CVL) over time were associated with the rate of new HIV diagnoses (NDs).

METHODS

HIV-1-positive individuals referred to our institute and permanently residing in our province were considered for inclusion in the study. A total of 861 HIV-infected adults with at least one HIV RNA measurement (12 530 measurements in total) between 2008 and 2014 were included. Viraemia copy-years were calculated from all HIV RNA values for each patient using the trapezoidal rule; multiple CVL indicators were considered. Total NDs and recent infections (< 1 year) were analysed separately. The association between NDs and CVL was tested by means of mixed Poisson models, with CVL as a fixed effect and year as a random effect.

RESULTS

The incidence of NDs was 2.28 per 100 000 residents in 2008 and 2.52 per 100 000 residents in 2014. Total numbers of NDs and recent infections did not vary significantly over time (P for trend 0.879 and 0.39, respectively). Mean HIV RNA decreased from 31 095.8 HIV-1 RNA copies/mL in 2008 to 21 231.5 copies/mL in 2014 (P < 0.001); a downward trend was always observed regardless of the CVL indicator considered. Depending on the indicator, there were some differences in CVL by patient characteristics. The most substantial contributors to CVL appeared to be male individuals, men who have sex with men (MSM), non-Italians, and untreated subjects (all P < 0.05). The relative risk of ND increased among Italians and MSM with an increasing proportion of subjects having an undetectable HIV RNA, and decreased in the same population with increasing levels of CVL.

CONCLUSIONS

In our setting, CVL represented a good marker of access to care and treatment; however, reduced CVL did not coincide with a reduction in the rate of NDs.

Trends in Incidences and Risk Factors for Hepatocellular Carcinoma and Other Liver Events in HIV and Hepatitis C Virus-coinfected Individuals From 2001 to 2014: A Multicohort Study

BACKGROUND

While liver-related deaths in human immunodeficiency virus (HIV) and hepatitis C virus (HCV)-coinfected individuals have declined over the last decade, hepatocellular carcinoma (HCC) may have increased. We describe the epidemiology of HCC and other liver events in a multicohort collaboration of HIV/HCV-coinfected individuals.

METHODS

We studied HCV antibody-positive adults with HIV in the EuroSIDA study, the Southern Alberta Clinic Cohort, the Canadian Co-infection Cohort, and the Swiss HIV Cohort study from 2001 to 2014. We calculated the incidence of HCC and other liver events (defined as liver-related deaths or decompensations, excluding HCC) and used Poisson regression to estimate incidence rate ratios.

RESULTS

Our study comprised 7229 HIV/HCV-coinfected individuals (68% male, 90% white). During follow-up, 72 cases of HCC and 375 other liver events occurred, yielding incidence rates of 1.6 (95% confidence interval [CI], 1.3, 2.0) and 8.6 (95% CI, 7.8, 9.5) cases per 1000 person-years of follow-up, respectively. The rate of HCC increased 11% per calendar year (95% CI, 4%, 19%) and decreased 4% for other liver events (95% CI, 2%, 7%), but only the latter remained statistically significant after adjustment for potential confounders. Older age, cirrhosis, and low current CD4 cell count were associated with a higher incidence of both HCC and other liver events.

CONCLUSIONS

In HIV/HCV-coinfected individuals, the crude incidence of HCC increased from 2001 to 2014, while other liver events declined. Individuals with cirrhosis or low current CD4 cell count are at highest risk of developing HCC or other liver events.