CD4 decline in seroconverter and seroprevalent individuals in the precombination of antiretroviral therapy era

Immediate and long-term outcomes after treat-all among people living with HIV in China: an interrupted time series analysis

BACKGROUND

In 2003, China implemented free antiretroviral therapy (ART) for people living with HIV (PLHIV), establishing an eligibility threshold of CD4 < 200 cells/μl. Subsequently, the entry criteria were revised in 2012 (eligibility threshold: CD4 ≤ 350 cells/μl), 2014 (CD4 ≤ 500 cells/μl), and 2016 (treat-all). However, the impact of treat-all policy on HIV care and treatment indicators in China is unknown. We aimed to elucidate the immediate and long-term impact of the implementation of treat-all policy in China.

METHODS

Anonymized programmatic data on ART initiation and collection in PLHIV who newly started ART were retrieved between 1 January 2015 and 31 December 2019, from two provincial and municipal Centers for Disease Control and Prevention and ten major infectious disease hospitals specialized in HIV care in China. We used Poisson and quasi-Poisson segmented regression models to estimate the immediate and long-term impact of treat-all on three key indicators: monthly proportion of 30-day ART initiation, mean CD4 counts (cells/μl) at ART initiation, and mean estimated time from infection to diagnosis (year). We built separate models according to gender, age, route of transmission and region.

RESULTS

Monthly data on ART initiation and collection were available for 75,516 individuals [gender: 83.8% males; age: median 39 years, interquartile range (IQR): 28-53; region: 18.5% Northern China, 10.9% Northeastern China, 17.5% Southern China, 49.2% Southwestern China]. In the first month of treat-all, compared with the contemporaneous counterfactual, there was a significant increase in proportion of 30-day ART initiation [+ 12.6%, incidence rate ratio (IRR) = 1.126, 95% CI: 1.033-1.229; P = 0.007] and mean estimated time from infection to diagnosis (+ 7.0%, IRR = 1.070, 95% CI: 1.021-1.120; P = 0.004), while there was no significant change in mean CD4 at ART initiation (IRR = 0.990, 95% CI: 0.956-1.026; P = 0.585). By December 2019, the three outcomes were not significantly different from expected levels. In the stratified analysis, compared with the contemporaneous counterfactual, mean CD4 at ART initiation showed significant increases in Northern China (+ 3.3%, IRR = 1.033, 95% CI: 1.001-1.065; P = 0.041) and Northeastern China (+ 8.0%, IRR = 1.080, 95% CI: 1.003-1.164; P = 0.042) in the first month of treat-all; mean estimated time from infection to diagnosis showed significant increases in male (+ 5.6%, IRR = 1.056, 95% CI: 1.010-1.104; P = 0.016), female (+ 14.8%, IRR = 1.148, 95% CI: 1.062-1.240; P < 0.001), aged 26-35 (+ 5.3%, IRR = 1.053, 95% CI: 1.001-1.109; P = 0.048) and > 50 (+ 7.8%, IRR = 1.078, 95% CI: 1.000-1.161; P = 0.046), heterosexual transmission (+ 12.4%, IRR = 1.124, 95% CI: 1.042-1.213; P = 0.002) and Southwestern China (+ 12.9%, IRR = 1.129, 95% CI: 1.055-1.208; P < 0.001) in the first month of treat-all.

CONCLUSIONS

The implementation of treat-all policy in China was associated with a positive effect on HIV care and treatment outcomes. To advance the work of rapid ART, efforts should be made to streamline the testing and ART initiation process, provide comprehensive support services, and address the issue of uneven distribution of medical resources.

Time From HIV Infection to Diagnosis in the U.S., 2014-2018

INTRODUCTION

Understanding the role of sociologic, structural, and biomedical factors that influence the length of time from HIV infection to diagnosis and reducing the time from infection to diagnosis are critical for achieving the goals of the Ending the HIV Epidemic initiative. In a retrospective analysis, the length of time from HIV infection to diagnosis and its association with individual- and facility-level attributes are determined.

METHODS

Data reported by December 2019 to the U.S. National HIV Surveillance System for people with HIV diagnosed during 2014-2018 were analyzed during December 2020. A CD4 depletion model was used to estimate the time from HIV infection to diagnosis.

RESULTS

During 2018, the median time from HIV infection to diagnosis was shorter for those infections diagnosed using the rapid testing algorithm (30.3 months, 95% CI=25.5, 34.5) than those diagnosed using the recommended (41.0 months, 95% CI=39.5, 42.0), traditional (37.0 months, 95% CI=29.5, 43.5), or other (35.5 months, 95% CI=32.5, 38.0) diagnostic testing algorithms. From 2014 to 2018, the time from HIV infection to diagnosis remained stable overall for all testing methods except for the traditional diagnostic testing algorithm. In multivariate analyses, those more likely to have HIV diagnosed closer to the time of infection were younger, were White, had transmission risk factors of injection drug use or heterosexual contact (for female individuals) or male-to-male sexual contact and injection drug use, or had HIV diagnosed at a correctional or screening facility (p<0.01).

CONCLUSIONS

Providing access to expanded testing, including rapid testing in nonclinical settings, is likely to result in a decrease in the length of time a person is unaware of their HIV infection and thus reduce onward transmission of HIV infection.

Estimated time from HIV infection to diagnosis and diagnosis to first viral suppression during 2014-2018

OBJECTIVE

To examine changes in the lengths of time from HIV infection to diagnosis (Infx-to-Dx) and from diagnosis to first viral suppression (Dx-to-VS), two periods during which HIV can be transmitted.

DESIGN

Data from the National HIV Surveillance System (NHSS) for persons who were aged at least 13 years at the time of HIV diagnosis during 2014-2018 and resided in one of 33 United States jurisdictions with complete laboratory reporting.

METHODS

The date of HIV infection was estimated based on a CD4+-depletion model. Date of HIV diagnosis, and dates and results of first CD4+ test and first viral suppression (<200 copies/ml) after diagnosis were reported to NHSS through December 2019. Trends for Infx-to-Dx and Dx-to-VS intervals were examined using estimated annual percentage change.

RESULTS

During 2014-2018, among persons aged at least 13 years, 133 413 HIV diagnoses occurred. The median length of infx-to-Dx interval shortened from 43 months (2014) to 40 months (2018), a 1.5% annual decrease (7% relative change over the 5-year period). The median length of Dx-to-VS interval shortened from 7 months (2014) to 4 months (2018), an 11.4% annual decrease (42.9% relative change over the 5-year period). Infx-to-Dx intervals shortened in only some subgroups, whereas Dx-to-VS intervals shortened in all groups by sex, transmission category, race/ethnicity, age, and CD4+ count at diagnosis.

CONCLUSION

The shortened Infx-to-Dx and Dx-to-VS intervals suggest progress in promoting HIV testing and earlier treatment; however, diagnosis delays continue to be substantial. Further shortening both intervals and eliminating disparities are needed to achieve Ending the HIV Epidemic goals.

Discriminating Between Premigration and Postmigration HIV Acquisition Using Surveillance Data

BACKGROUND

Migrant populations are overrepresented among persons diagnosed with HIV in the European Union and the European Economic Area. Understanding the timing of HIV acquisition (premigration or postmigration) is crucial for developing public health interventions and for producing reliable estimates of HIV incidence and the number of people living with undiagnosed HIV infection. We summarize a recently proposed method for determining the timing of HIV acquisition and apply it to both real and simulated data.

METHODS

The considered method combines estimates from a mixed model, applied to data from a large seroconverters' cohort, with biomarker measurements and individual characteristics to derive probabilities of premigration HIV acquisition within a Bayesian framework. The method is applied to a subset of data from the European Surveillance System (TESSy) and simulated data.

FINDINGS

Simulation study results showed good performance with the probabilities of correctly classifying a premigration case or a postmigration case being 87.4% and 80.4%, respectively. Applying the method to TESSy data, we estimated the proportions of migrants who acquired HIV in the destination country were 31.9%, 37.1%, 45.3%, and 45.2% for those originating from Africa, Europe, Asia, and other regions, respectively.

CONCLUSIONS

Although the considered method was initially developed for cases with multiple biomarkers' measurements, its performance, when applied to data where only one CD4 count per individual is available, remains satisfactory. Application of the method to TESSy data, estimated that a substantial proportion of HIV acquisition among migrants occurs in destination countries, having important implications for public health policy and programs.

Post-migration acquisition of HIV: Estimates from four European countries, 2007 to 2016

BackgroundThe assumption that migrants acquire human immunodeficiency virus (HIV) before migration, particularly those from high prevalence areas, is common.AimWe assessed the place of HIV acquisition of migrants diagnosed in four European countries using surveillance data.MethodsUsing CD4+ T-cell count trajectories modelled to account for seroconversion bias, we estimated infection year of newly HIV-diagnosed migrants residing in the United Kingdom (UK), Belgium, Sweden and Italy with a known arrival year and CD4+ T-cell count at diagnosis. Multivariate analyses identified predictors for post-migration acquisition.ResultsBetween 2007 and 2016, migrants constituted 56% of people newly diagnosed with HIV in the UK, 62% in Belgium, 72% in Sweden and 29% in Italy. Of 23,595 migrants included, 60% were born in Africa and 70% acquired HIV heterosexually. An estimated 9,400 migrants (40%; interquartile range (IQR): 34-59) probably acquired HIV post-migration. This proportion was similar by risk group, sex and region of birth. Time since migration was a strong predictor of post-migration HIV acquisition: 91% (IQR: 87-95) among those arriving 10 or more years prior to diagnosis; 30% (IQR: 21-37) among those 1-5 years prior. Younger age at arrival was a predictor: 15-18 years (81%; IQR: 74-86), 19-25 years (53%; IQR: 45-63), 26-35 years (37%; IQR: 30-46) and 36 years and older (25%; IQR: 21-33).ConclusionsMigrants, regardless of origin, sex and exposure to HIV are at risk of acquiring HIV post-migration to Europe. Alongside accessible HIV testing, prevention activities must target migrant communities.

Estimates of the Time From Seroconversion to Antiretroviral Therapy Initiation Among People Newly Diagnosed With Human Immunodeficiency Virus From 2006 to 2015, New York City

BACKGROUND

We estimated the time from human immunodeficiency virus (HIV) seroconversion to antiretroviral therapy (ART) initiation during an era of expanding HIV testing and treatment efforts.

METHODS

Applying CD4 depletion parameters from seroconverter cohort data to our population-based sample, we related the square root of the first pretreatment CD4 count to time of seroconversion through a linear mixed model and estimated the time from seroconversion.

RESULTS

Among 28 162 people diagnosed with HIV during 2006-2015, 89% initiated ART by June 2017. The median CD4 count at diagnosis increased from 326 (interquartile range [IQR], 132-504) cells/µL to 390 (IQR, 216-571) cells/µL from 2006 to 2015. The median time from estimated seroconversion to ART initiation decreased by 42% from 6.4 (IQR, 3.3-11.4) years in 2006 to 3.7 (IQR, 0.5-8.3) years in 2015. The time from estimated seroconversion to diagnosis decreased by 28%, from a median of 4.6 (IQR, 0.5-10.5) years to 3.3 (IQR, 0-8.1) years from 2006 to 2015, and the time from diagnosis to ART initiation reduced by 60%, from a median of 0.5 (IQR, 0.2-2.1) years to 0.2 (IQR, 0.1-0.3) years from 2006 to 2015.

CONCLUSIONS

The estimated time from seroconversion to ART initiation was reduced in tandem with expanded HIV testing and treatment efforts. While the time from diagnosis to ART initiation decreased to 0.2 years, the time from seroconversion to diagnosis was 3.3 years among people diagnosed in 2015, highlighting the need for more effective strategies for earlier HIV diagnosis.

Asymptomatic Adolescent HIV: Identifying a Role for Universal HIV Screening in the Pediatric Emergency Department

Adolescents account for most undiagnosed HIV infections in the United States. Although the Centers for Disease Control and Prevention (CDC) recommends universal HIV screening for all patients ≥13 years, <10% of adolescents have been tested for HIV. To identify earlier opportunities for adolescent HIV prevention and diagnosis in a region of high HIV prevalence, we sought to describe pediatric emergency department (PED) visits made by a retrospective cohort of adolescents who were later diagnosed with HIV as young adults (<25 years) through an adult emergency department (ED) universal HIV screening program. CD4+ count was used to estimate the time of HIV infection before diagnosis and all PED visits in the 10 years before diagnosis were analyzed. Universal HIV screening in the adult ED diagnosed 193 young adults (median 22 years; 90% men; 29% stage 3); 70% had CD4+ at diagnosis that was used to estimate time of infection (mean 3.8 years). Thirty-eight HIV-infected young adults had a total of 109 PED visits in the 10 years before HIV diagnosis. Sexual history was documented in 12% of PED visits and a sexually transmitted infection test was sent in 6%. Ten HIV-infected young adults had 26 PED visits during the time in which they were likely already infected with HIV, each a potential missed opportunity for earlier diagnosis. HIV-infected and at-risk adolescents are underrecognized in PED visits. Implementation of CDC-recommended universal screening may lead to earlier diagnoses and improve outcomes; the PED may also be critical in identifying adolescents eligible for preexposure prophylaxis.

How to Evolve the Response to the Global HIV Epidemic With New Metrics and Targets Based on Pre-Treatment CD4 Counts

PURPOSE OF THE REVIEW

Early diagnosis and treatment of HIV following seroconversion improves individual and population health. Using published data on pre-treatment CD4 cell counts, we benchmarked the level of immunodeficiency at HIV diagnosis and ART initiation in the "real world" against those of the treatment and control arms of landmark controlled trials that successfully reduced HIV-related deaths (INSIGHT/START) and onward HIV transmission (HPTN 052).

RECENT FINDINGS

The median CD4 count in the treatment vs. control arms of the INSIGHT/START trial and HPTN 052 were 650 vs. 408 cells/μL and 442 vs. 221 cells/μL, respectively. In the real world, recent global estimates of the median CD4 count at start of ART range from 234 to 350 cells/μL, and only 25% of those initiating ART do so early (i.e., with CD4 > 500 cells/μL). Recent global data on trends in the median CD4 count at diagnosis and ART initiation are not encouraging. We identify a critical need for new targets and metrics for persons newly diagnosed with HIV, newly enrolling in HIV care, and newly initiating ART, based on pre-treatment CD4 counts, to help increase the focus of implementation efforts on achieving earlier diagnosis, linkage to care, and ART initiation.

Determining the likely place of HIV acquisition for migrants in Europe combining subject-specific information and biomarkers data

In most HIV-positive individuals, infection time is only known to lie between the time an individual started being at risk for HIV and diagnosis time. However, a more accurate estimate of infection time is very important in certain cases. For example, one of the objectives of the Advancing Migrant Access to Health Services in Europe (aMASE) study was to determine if HIV-positive migrants, diagnosed in Europe, were infected pre- or post-migration. We propose a method to derive subject-specific estimates of unknown infection times using information from HIV biomarkers' measurements, demographic, clinical, and behavioral data. We assume that CD4 cell count (CD4) and HIV-RNA viral load trends after HIV infection follow a bivariate linear mixed model. Using post-diagnosis CD4 and viral load measurements and applying the Bayes' rule, we derived the posterior distribution of the HIV infection time, whereas the prior distribution was informed by AIDS status at diagnosis and behavioral data. Parameters of the CD4-viral load and time-to-AIDS models were estimated using data from a large study of individuals with known HIV infection times (CASCADE). Simulations showed substantial predictive ability (e.g. 84% of the infections were correctly classified as pre- or post-migration). Application to the aMASE study (n = 2009) showed that 47% of African migrants and 67% to 72% of migrants from other regions were most likely infected post-migration. Applying a Bayesian method based on bivariate modeling of CD4 and viral load, and subject-specific information, we found that the majority of HIV-positive migrants in aMASE were most likely infected after their migration to Europe.

Modeling HIV disease progression and transmission at population-level: The potential impact of modifying disease progression in HIV treatment programs

INTRODUCTION

Mathematical models that incorporate HIV disease progression dynamics can estimate the potential impact of strategies that delay HIV disease progression and reduce infectiousness for persons not on antiretroviral therapy (ART). Suppressive treatment of HIV-positive persons co-infected with herpes simplex virus-2 (HSV-2) with valacyclovir, an HSV-2 antiviral, can lower HIV viral load, but the impact of partially-suppressive valacyclovir relative to fully-suppressive ART on population HIV transmission has not been estimated.

METHODS

We modeled HIV disease progression as a function of changes in viral load and CD4 count over time among ART naïve persons. The disease progression Markov model was nested within a dynamic model of HIV transmission at population level. We assumed that valacyclovir reduced HIV viral load by 1.23 log copies/μL, and that persons treated with valacyclovir initiated ART more rapidly when their CD4 fell below 500 due to retention in HIV care. We estimated the potential impact of valacyclovir on onward transmission of HIV in three scenarios of different ART and valacyclovir population coverage.

RESULTS

The average duration of HIV infection was 9.5 years. The duration of disease before reaching CD4 200cells/μL was 2.53 years longer for females than males. Relative to a baseline of ART initiation at CD4≤500cells/μL, the valacyclovir scenario resulted in 167,000 fewer HIV infections over ten years, with an incremental cost-effectiveness ratio (ICER) of $5276 per HIV infection averted. A Test and Treat scenario with 70% ART coverage and no valacyclovir resulted in 350,000 fewer HIV infections at an ICER of $2822 and $812 per HIV infection averted and QALY gained, respectively.

CONCLUSION

Even when compared with valacyclovir suppression, a drug that reduces HIV viral load, universal treatment for HIV is the optimal strategy for averting new infections and increasing public health benefit. Universal HIV treatment would most effectively and efficiently reduce the HIV burden.

Impact of CD4 and CD8 dynamics and viral rebounds on loss of virological control in HIV controllers

Objective

HIV controllers (HICs) spontaneously maintain HIV viral replication at low level without antiretroviral therapy (ART), a small number of whom will eventually lose this ability to control HIV viremia. The objective was to identify factors associated with loss of virological control.

Methods

HICs were identified in COHERE on the basis of ≥5 consecutive viral loads (VL) ≤500 copies/mL over ≥1 year whilst ART-naive, with the last VL ≤500 copies/mL measured ≥5 years after HIV diagnosis. Loss of virological control was defined as 2 consecutive VL >2000 copies/mL. Duration of HIV control was described using cumulative incidence method, considering loss of virological control, ART initiation and death during virological control as competing outcomes. Factors associated with loss of virological control were identified using Cox models. CD4 and CD8 dynamics were described using mixed-effect linear models.

Results

We identified 1067 HICs; 86 lost virological control, 293 initiated ART, and 13 died during virological control. Six years after confirmation of HIC status, the probability of losing virological control, initiating ART and dying were 13%, 37%, and 2%. Current lower CD4/CD8 ratio and a history of transient viral rebounds were associated with an increased risk of losing virological control. CD4 declined and CD8 increased before loss of virological control, and before viral rebounds.

Discussion

Expansion of CD8 and decline of CD4 during HIV control may result from repeated low-level viremia. Our findings suggest that in addition to superinfection, other mechanisms, such as low grade viral replication, can lead to loss of virological control in HICs.

Estimating HIV Incidence, Time to Diagnosis, and the Undiagnosed HIV Epidemic Using Routine Surveillance Data

BACKGROUND

Estimates of the size of the undiagnosed HIV-infected population are important to understand the HIV epidemic and to plan interventions, including "test-and-treat" strategies.

METHODS

We developed a multi-state back-calculation model to estimate HIV incidence, time between infection and diagnosis, and the undiagnosed population by CD4 count strata, using surveillance data on new HIV and AIDS diagnoses. The HIV incidence curve was modelled using cubic splines. The model was tested on simulated data and applied to surveillance data on men who have sex with men in The Netherlands.

RESULTS

The number of HIV infections could be estimated accurately using simulated data, with most values within the 95% confidence intervals of model predictions. When applying the model to Dutch surveillance data, 15,400 (95% confidence interval [CI] = 15,000, 16,000) men who have sex with men were estimated to have been infected between 1980 and 2011. HIV incidence showed a bimodal distribution, with peaks around 1985 and 2005 and a decline in recent years. Mean time to diagnosis was 6.1 (95% CI = 5.8, 6.4) years between 1984 and 1995 and decreased to 2.6 (2.3, 3.0) years in 2011. By the end of 2011, 11,500 (11,000, 12,000) men who have sex with men in The Netherlands were estimated to be living with HIV, of whom 1,750 (1,450, 2,200) were still undiagnosed. Of the undiagnosed men who have sex with men, 29% (22, 37) were infected for less than 1 year, and 16% (13, 20) for more than 5 years.

CONCLUSIONS

This multi-state back-calculation model will be useful to estimate HIV incidence, time to diagnosis, and the undiagnosed HIV epidemic based on routine surveillance data.

Does rapid HIV disease progression prior to combination antiretroviral therapy hinder optimal CD4+ T-cell recovery once HIV-1 suppression is achieved?

Objective:

This article compares trends in CD4⁺ T-cell recovery and proportions achieving optimal restoration (≥500 cells/μl) after viral suppression following combination antiretroviral therapy (cART) initiation between rapid and nonrapid progressors.

Methods:

We included HIV-1 seroconverters achieving viral suppression within 6 months of cART. Rapid progressors were individuals experiencing at least one CD4⁺ less than 200 cells/μl within 12 months of seroconverters before cART. We used piecewise linear mixed models and logistic regression for optimal restoration.

Results:

Of 4024 individuals, 294 (7.3%) were classified as rapid progressors. At the same CD4⁺ T-cell count at cART start (baseline), rapid progressors experienced faster CD4⁺ T-cell increases than nonrapid progressors in first month [difference (95% confidence interval) in mean increase/month (square root scale): 1.82 (1.61; 2.04)], which reversed to slightly slower increases in months 1–18 [−0.05 (−0.06; −0.03)] and no significant differences in 18–60 months [−0.003 (−0.01; 0.01)]. Percentage achieving optimal restoration was significantly lower for rapid progressors than nonrapid progressors at months 12 (29.2 vs. 62.5%) and 36 (47.1 vs. 72.4%) but not at month 60 (70.4 vs. 71.8%). These differences disappeared after adjusting for baseline CD4⁺ T-cell count: odds ratio (95% confidence interval) 0.86 (0.61; 1.20), 0.90 (0.38; 2.17) and 1.56 (0.55; 4.46) at months 12, 36 and 60, respectively.

Conclusion:

Among people on suppressive antiretroviral therapy, rapid progressors experience faster initial increases of CD4⁺ T-cell counts than nonrapid progressors, but are less likely to achieve optimal restoration during the first 36 months after cART, mainly because of lower CD4⁺ T-cell counts at cART initiation.

Inferring HIV incidence from case surveillance with CD4+ cell counts

BACKGROUND

In some countries, HIV surveillance is based on case-reporting of newly diagnosed infections. We present a new back-projection method for estimating HIV-incidence trends using individuals' CD4 cell counts at diagnosis.

METHODS

On the basis of a review of CD4 cell count distributions among HIV-uninfected people, CD4 cell count following primary infection, and rates of CD4 cell count decline over time among people with HIV, we simulate the expected distribution in time between infection and diagnosis. Applying this to all diagnosed individuals provides a distribution of likely infection times and estimates for population incidence, level of undiagnosed HIV, and the average time from infection to diagnosis each year. We applied this method to the national HIV case surveillance data of Australia for 1983-2013.

RESULTS

The estimated number of new HIV infections in Australia in 2013 was 912 (95% uncertainty bound 835-1002). We estimate that 2280 (95% uncertainty bound 1900-2830) people were living with undiagnosed HIV at the end of 2013, corresponding to approximately 9.4% (95% uncertainty bound 7.8-10.1%) of all people living with HIV. With increases in the average CD4 count at diagnosis, the inferred HIV testing rate has been increasing over time and the estimated mean and median times between infection and diagnosis have decreased substantially. However, the estimated mean time between infection and diagnosis is considerably greater than the median, indicating that some people remain undiagnosed for long periods. Differences were found between cases attributable to male homosexual exposure versus other cases.

CONCLUSION

This methodology provides a novel way of estimating population incidence by combining diagnosis dates and CD4 cell counts at diagnosis.

Late presentation to HIV testing is overestimated when based on the consensus definition

Objectives

In 2011, a consensus was reached defining “late presenters” (LPs) as individuals presenting for care with a CD4 count < 350 cells/μL or with an AIDS‐defining event, regardless of CD4 count. However, a transient low CD4 count is not uncommon in recent infections. The objective of this study was to investigate how measurements of late presentation change if the clinical stage at the time of diagnosis is taken into account.

Methods

Case surveillance data for newly diagnosed patients in Belgium in 1998–2012 were analysed, including CD4 count at diagnosis, the presence of AIDS‐defining events, and recent infections (< 6 months) as reported by clinicians in the case of acute illness or a recent negative test. First, proportions of LPs were calculated according to the consensus definition. Secondly, LPs were reclassified as “nonlate” if infections were reported as recent.

Results

A total of 7949 HIV diagnoses were included in the study. Recent infections were increasingly reported over time, accounting for 8.2% of new infections in 1998 and 37.5% in 2012. The consideration of clinical stage significantly modified the proportion of LPs: 18.2% of men who have sex with men (MSM) diagnosed in 2012 would be classified as LPs instead of 30.9% using the consensus definition (P < 0.001). The proportion of patients misclassified as LPs increased significantly over time: 5% in MSM in 1998 vs. 41% in 2012.

Conclusions

This study suggests that low CD4 counts in recent infections may lead to overestimation of late presentation when applying the consensus definition. The impact of transient CD4 count on late presentation estimates should be assessed and, if relevant, the introduction of clinical stage in the definition of late presentation should be considered.

Impact of exposure to intimate partner violence on CD4+ and CD8+ T cell decay in HIV infected women: longitudinal study

Intimate partner violence (IPV) is a risk factor for HIV acquisition in many settings, but little is known about its impact on cellular immunity especially in HIV infected women, and if any impact differs according to the form of IPV. We tested hypotheses that exposure to IPV, non-partner rape, hunger, pregnancy, depression and substance abuse predicted change in CD4+ and CD8+ T-cell count in a dataset of 103 HIV infected young women aged 15-26 enrolled in a cluster randomised controlled trial. Multiple regression models were fitted to measure rate of change in CD4 and CD8 and including terms for age, person years of CD4+/CD8+ T-cell observation, HIV positivity at baseline, and stratum. Exposure variables included drug use, emotional, physical or sexual IPV exposure, non-partner rape, pregnancy and food insecurity. Mean CD4+ T cell count at baseline (or first HIV+ test) was 567.6 (range 1121-114). Participants were followed for an average of 1.3 years. The magnitude of change in CD4 T-cells was significantly associated with having ever experienced emotional abuse from a current partner at baseline or first HIV+ test (Coeff -132.9 95% CI -196.4, -69.4 p<0.0001) and drug use (Coeff -129.9 95% CI -238.7, -21.2 p=0.02). It was not associated with other measures. The change in CD8 T-cells was associated with having ever experienced emotional abuse at baseline or prior to the first HIV+ test (Coeff -178.4 95%CI -330.2, -26.5 p=0.02). In young ART-naive HIV positive women gender-based violence exposure in the form of emotional abuse is associated with a faster rate of decline in markers of cellular immunity. This highlights the importance of attending to emotional abuse when studying the physiological impact of IPV experience and the mechanisms of its impact on women's health.

Evaluation of rapid progressors in HIV infection as an extreme phenotype

DESIGN

Rapid CD4 cell loss represents an HIV phenotype used to identify causal variants of accelerated disease progression. The optimal rate and threshold for identifying this extreme phenotype in recently infected individuals is unclear.

METHODS

Using a cohort of patients with known dates of HIV-1 seroconversion (SC), CASCADE (Concerted Action on SeroConversion on AIDS and Death in Europe), we identified proportions experiencing nadir CD4 cell levels within 1 year of SC, and assessed their mean AIDS-free survival time at 10-year follow-up and hazard of AIDS/death, compared with those whose CD4 remained >500 cells per cubic millimeter. Follow-up was censored at December 31, 1996 to avoid bias due to combination antiretroviral therapy initiation.

RESULTS

Of 4876 individuals, 2.8%, 7.3%, and 24.9% experienced ≥1 CD4 <100, 200, and 350 cells per cubic millimeter, respectively, within 1 year of SC. Minimum CD4 levels of 30, 166, 231, and 506 cells per cubic millimeter were experienced during this period by 1%, 5%, 10%, and 50% of individuals, respectively. Mean (95% confidence interval) AIDS-free survival at 10 years follow-up was 2.9 (2.3 to 3.6), 5.5 (5.0 to 6.1), 6.7 (6.5 to 7.0), 7.4 (7.2 to 7.6), and 8.1 (7.9 to 8.3), for those with minimum counts ≤100, 100-200, 200-350, 350-500, >500 cells per cubic millimeter, respectively. Using counts of >500 cells per cubic millimeter as reference, the hazard ratios (95% confidence interval) of AIDS/death were 15.0 (11.9 to 18.9), 3.6 (2.9 to 4.5), 2.1 (1.8 to 2.4), and 1.5 (1.3 to 1.7), respectively. The hazard ratio increased to 37.5 (26.5 to 53.1) when a minimum CD4 count <100 was confirmed within 1 year of SC.

CONCLUSION

At least 1 CD4 ≤100 cells per cubic millimeter within the first year of SC identifies a rare group of individuals at high risk of disease progression and could form the basis for defining the rapid progressor phenotype.

Delayed HIV diagnosis common in Sweden, 2003-2010

Background

Early diagnosis of HIV is important for the prognosis of individual patients, because antiretroviral treatment can be started at the appropriate time, and for public health, because transmission can be prevented.

Methods

Data were collected from 767 HIV patients who were diagnosed in Sweden during 2003–2010 and were infected in Sweden or born in Sweden and infected abroad. A recent infection testing algorithm (RITA) was applied to BED-EIA test results (OD-n < 0.8), CD4 counts (≥ 200 cells/μl), and clinical information. A recent infection classification was used as indicator for early diagnosis. Time trends in early diagnosis were investigated to detect population changes in HIV testing behavior. Patients with early diagnosis were compared to patients with delayed diagnosis with respect to age, gender, transmission route, and country of infection (Sweden or abroad).

Results

Early diagnosis was observed in 271 patients (35%). There was no statistically significant time trend in the yearly percentage of patients with early diagnosis in the entire study group (p = 0.836) or in subgroups. Early diagnosis was significantly more common in men who have sex men (MSM) (45%) than in heterosexuals (21%) and injecting drug users (27%) (p < 0.001 and p = 0.001, respectively) in both univariate and multivariable analyses. The only other factor that remained associated with early diagnosis in multivariable analysis was young age group.

Conclusion

Approximately one-third of the study patients were diagnosed early with no significant change over time. Delayed HIV diagnosis is a considerable problem in Sweden, which does not appear to diminish.

The undiagnosed HIV epidemic in France and its implications for HIV screening strategies

BACKGROUND

Describing the undiagnosed HIV-infected population is essential for guiding HIV screening policy, implementing interventions, and resource planning.

METHODS

We used French national HIV surveillance data and a back-calculation approach to estimate the number of undiagnosed HIV-infected individuals in France and the distribution of time since HIV infection among undiagnosed individuals. We also used data on CD4⁺ cell count decline to assess the CD4⁺ cell count distribution among undiagnosed individuals.

RESULTS

We estimated that 29,000 [95% confidence interval (CI): 24,200-33,900] individuals were living with undiagnosed HIV infection at the end of 2010. Of these, 28.7% (95% CI: 27.1-30.4) were infected less than a year ago, 16.4% (95% CI: 15.0-17.8) more than 5 years ago, and 59.6% (95% CI: 59.2-59.8) were eligible for antiretroviral treatment (CD4⁺ cell count less than 500 cells/μl) according to the 2010 French guidelines. Men represented 70.0% of the undiagnosed HIV-infected individuals and had lower CD4⁺ cell counts than women. The numbers of undiagnosed infections in MSM, non-French national heterosexuals, and French national heterosexuals were similar (9200, 9300, 10,000, respectively). However, because of differences in group size, undiagnosed HIV prevalence varied significantly between these groups (2.95, 0.36, 0.03%, respectively; P less than 0.001).

CONCLUSION

Our findings suggest that many undiagnosed HIV-infected individuals were eligible for treatment and, thus, lack of HIV diagnosis is a lost chance for them; many more heterosexuals than MSM will need to be tested to find those undiagnosed; and universal screening of men may be cost-effective, especially in the areas most affected by the epidemic, such as the Paris region.

Predicting the population impact of increased HIV testing and treatment in Australia

Introduction The treatment as prevention strategy has gained popularity as a way to reduce the incidence of HIV by suppressing viral load such that transmission risk is decreased. The effectiveness of the strategy also requires early diagnosis.

METHODS

Informed by data on the influence of diagnosis and treatment on reducing transmission risk, a model simulated the impact of increasing testing and treatment rates on the expected incidence of HIV in Australia under varying assumptions of treatment efficacy and risk compensation. The model utilises Australia's National HIV Registry data, and simulates disease progression, testing, treatment, transmission and mortality.

RESULTS

Decreasing the average time between infection and diagnosis by 30% is expected to reduce population incidence by 12% (~126 cases per year, 95% confidence interval (CI): 82-198). Treatment of all people living with HIV with CD4 counts <500cellsμL(-1) is expected to reduce new infections by 30.9% (95% CI: 15.9-37.6%) at 96% efficacy if no risk compensation occurs. The number of infections could increase up to 12.9% (95% CI: 20.1-7.4%) at 26% efficacy if a return to prediagnosis risk levels occur.

CONCLUSION

Treatment as prevention has the potential to prevent HIV infections but its effectiveness depends on the efficacy outside trial settings among men who have sex with men and the level of risk compensation. If antiretroviral therapy has high efficacy, risk compensation will not greatly change the number of infections. If the efficacy of antiretroviral therapy is low, risk compensation could lead to increased infections.

Modeling the impact of interventions along the HIV continuum of care in Newark, New Jersey

BACKGROUND

The human immunodeficiency virus (HIV) epidemic in Newark, New Jersey, is among the most severe in the United States. Prevalence ranges up to 3.3% in some groups. The aim of this study is to use a mathematical model of the epidemic in Newark to assess the impact of interventions along the continuum of care, leading to virologic suppression.

METHODS

A model was constructed of HIV infection including specific care-continuum steps. The model was calibrated to HIV/AIDS cases in Newark among different populations over a 10-year period. Interventions applied to model fits were increasing proportions tested, linked and retained in care, linked and adherent to treatment, and increasing testing frequency, high-risk-group testing, and adherence. Impacts were assessed by measuring incidence and death reductions 10 years postintervention.

RESULTS

The most effective interventions for reducing incidence were improving treatment adherence and increasing testing frequency and coverage. No single intervention reduced incidence in 2023 by >5%, and the most effective combination of interventions reduced incidence by approximately 16% (2%-24%). The most efficacious interventions for reducing deaths were increasing retention, linkage to care, testing coverage, and adherence. Increasing retention reduced deaths by approximately 27% (24%-29%); the most efficacious combination of interventions reduced deaths in 2023 by approximately 52% (46%-57%).

CONCLUSIONS

Reducing HIV deaths in Newark over a 10-year period may be a realizable goal, but reducing incidence is less likely. Our results highlight the importance of addressing leaks across the entire continuum of care and reinforcing efforts to prevention new HIV infections with additional interventions.

Role of HIV infection duration and CD4 cell level at initiation of combination anti-retroviral therapy on risk of failure

BACKGROUND

The development of HIV drug resistance and subsequent virological failure are often cited as potential disadvantages of early cART initiation. However, their long-term probability is not known, and neither is the role of duration of infection at the time of initiation.

METHODS

Patients enrolled in the UK Register of HIV seroconverters were followed-up from cART initiation to last HIV-RNA measurement. Through survival analysis we examined predictors of virologic failure (2HIV-RNA ≥400 c/l while on cART) including CD4 count and HIV duration at initiation. We also estimated the cumulative probabilities of failure and drug resistance (from the available HIV nucleotide sequences) for early initiators (cART within 12 months of seroconversion).

RESULTS

Of 1075 starting cART at a median (IQR) CD4 count 272 (190,370) cells/mm(3) and HIV duration 3 (1,6) years, virological failure occurred in 163 (15%). Higher CD4 count at initiation, but not HIV infection duration at cART initiation, was independently associated with lower risk of failure (p=0.033 and 0.592 respectively). Among 230 patients initiating cART early, 97 (42%) discontinued it after a median of 7 months; cumulative probabilities of resistance and failure by 8 years were 7% (95% CI 4,11) and 19% (13,25), respectively.

CONCLUSION

Although the rate of discontinuation of early cART in our cohort was high, the long-term rate of virological failure was low. Our data do not support early cART initiation being associated with increased risk of failure and drug resistance.

Effect of HCV infection on cause-specific mortality after HIV seroconversion, before and after 1997

BACKGROUND & AIMS

Individuals with human immunodeficiency virus (HIV) infection frequently also are infected with hepatitis C virus (HCV) (co-infection), but little is known about its effects on the progression of HIV-associated disease. We aimed to determine the effects of co-infection on mortality from HIV and/or acquired immune deficiency syndrome (AIDS), and hepatitis or liver disease, adjusting for the duration of HIV infection.

METHODS

We analyzed data from the 16 cohorts of the Concerted Action on Seroconversion to AIDS and Death in Europe (CASCADE) collaboration, which included information on HCV infection and cause of death. A competing-risks proportional subdistribution hazards model was used to evaluate the effect of HCV infection on the following causes of death: HIV- and/or AIDS-related, hepatitis- or liver-related, natural, and non-natural.

RESULTS

Of 9164 individuals with HIV infection and a known date of seroconversion, 2015 (22.0%) also were infected with HCV. Of 718 deaths, 395 (55.0%) were caused by HIV infection and/or AIDS, and 39 (5.4%) were caused by hepatitis or liver-related disease. Among individuals infected with only HIV or with co-infection, the mortality from HIV infection and/or AIDS-related causes and hepatitis or liver disease decreased significantly after 1997, when combination antiretroviral therapy became widely available. However, after 1997, HIV and/or AIDS-related mortality was higher among co-infected individuals than those with only HIV infection in each risk group: injection drug use (adjusted hazard ratio [aHR], 2.43; 95% confidence interval [CI], 1.14-5.20), sex between men and women or hemophilia (aHR, 3.43; 95% CI, 1.70-6.93), and sex between men (aHR, 3.11; 95% CI, 1.49-6.48). Compared with individuals infected with only HIV, co-infected individuals had a higher risk of death from hepatitis or liver disease.

CONCLUSIONS

Based on analysis of data from the CASCADE collaboration, since 1997, when combination antiretroviral therapy became widely available, individuals co-infected with HIV and HCV have had a higher risk of death from HIV and/or AIDS, and from hepatitis or liver disease, than patients infected with only HIV. It is necessary to evaluate the effects of HCV therapy on HIV progression.

Characterizing sexual histories of women before formal sex-work in south India from a cross-sectional survey: implications for HIV/STI prevention

Background

Interventions designed to prevent HIV and STIs in female sex-workers (FSWs) reach women after they formally enter the sex-trade. We aimed to characterize the pattern of sexual behaviour among FSWs from first-sex to when they identify as sex-workers (transition period) in a region with traditional (historically characterized by dedication into sex-work at first-sex) and non-traditional forms of sex-work.

Methods

We conducted a cross-sectional survey of 246 traditional and 765 non-traditional FSWs across three districts in Karnataka, India. We performed univariate and multivariate logistic regression to profile FSWs most likely to engage in a commercial first-sex before identifying as a sex-worker. Sexual life-course patterns were distinguished using univariate and multivariate linear regression based on key events associated with length of transition period.

Results

Overall, 266 FSWs experienced a commercial first-sex, of whom 45.9% (95% CI: 38.2,53.7) continued a long-term relationship with the first partner. In adjusted analysis, traditional FSWs were more likely to experience a commercial first-sex (AOR 52.5, 95% CI: 27.4,100.7). The average transition time was 8.8 years (SD 3.9), but there was considerable variability between respondents. Among women who experienced a commercial first-sex, a slower transition was independently associated with non-traditional sex-work, the presence of long-term partnerships during the transition period, and ongoing partnerships at time of entry into sex-work. In the absence of a commercial first-sex, a faster transition was associated with traditional sex-work and the dissolution of long-term partnerships, while a slower transition was associated with the presence of long-term partnerships and widowhood. Only 18.5% (95% CI: 12.7,26.2) and 47.3% (95% CI: 32.7,62.3) of women reported ‘always’ condom use with their long-term and occasional partners during the transition period, respectively.

Conclusions

FSWs identify as sex-workers several years after becoming sexually active, even when the first-sex is commercial in nature. Long-term partnerships are common after a commercial first-sex, and are associated with a delay in formally entering the sex-trade. The findings call for a better understanding of HIV/STI risk before FSWs identify as sex-workers, and an adaptive programme to reach this period of vulnerability.

Differences in HIV natural history among African and non-African seroconverters in Europe and seroconverters in sub-Saharan Africa

Introduction

It is unknown whether HIV treatment guidelines, based on resource-rich country cohorts, are applicable to African populations.

Methods

We estimated CD4 cell loss in ART-naïve, AIDS-free individuals using mixed models allowing for random intercept and slope, and time from seroconversion to clinical AIDS, death and antiretroviral therapy (ART) initiation by survival methods. Using CASCADE data from 20 European and 3 sub-Saharan African (SSA) cohorts of heterosexually-infected individuals, aged ≥15 years, infected ≥2000, we compared estimates between non-African Europeans, Africans in Europe, and Africans in SSA.

Results

Of 1,959 (913 non-Africans, 302 Europeans - African origin, 744 SSA), two-thirds were female; median age at seroconversion was 31 years. Individuals in SSA progressed faster to clinical AIDS but not to death or non-TB AIDS. They also initiated ART later than Europeans and at lower CD4 cell counts. In adjusted models, Africans (especially from Europe) had lower CD4 counts at seroconversion and slower CD4 decline than non-African Europeans. Median (95% CI) CD4 count at seroconversion for a 15–29 year old woman was 607 (588–627) (non-African European), 469 (442–497) (European - African origin) and 570 (551–589) (SSA) cells/µL with respective CD4 decline during the first 4 years of 259 (228–289), 155 (110–200), and 199 (174–224) cells/µL (p<0.01).

Discussion

Despite differences in CD4 cell count evolution, death and non-TB AIDS rates were similar across study groups. It is therefore prudent to apply current ART guidelines from resource-rich countries to African populations.

The Sydney Blood Bank Cohort: implications for viral fitness as a cause of elite control

PURPOSE OF REVIEW

The Sydney Blood Bank Cohort comprised eight individuals who were infected with an attenuated, nef/LTR-deleted strain of HIV-1 from a single donor. All six recipients with sufficient follow-up, as well as the donor, were long-term nonprogressors. Only three recipients have maintained undetectable plasma viral loads, allowing investigation of factors that determined elite control of attenuated HIV-1 infection.

RECENT FINDINGS

Follow-up of recipients showed that infection with this attenuated HIV-1 strain resulted in either low or absent viral replication in vivo for up to 29 years. The three patients without detectable viraemia have been studied for virological, genetic and immunological correlates of elite control. CD4 proliferation in vitro in response to p24 provided the clearest distinction of elite controllers from the slow progressors. Host factors are believed to differentiate the three elite controllers; only one, C135, has identifiable genetic polymorphisms that probably contributed to nonprogression: Δ32 CCR5 heterozygosity, HLA-B57 and HLA-DR13 alleles, in addition to infection with nef-defective HIV-1.

SUMMARY

Even nef-defective HIV-1 can lead to sufficient replication in vivo to enable viral evolution and eventual progression to immunodeficiency. Host factors modified the outcome of infection with attenuated HIV-1, as exemplified by the unique patient C135.