CD4+ T-Cell Count at Antiretroviral Therapy Initiation in the "Treat-All" Era in Rural South Africa: An Interrupted Time Series Analysis

Impact of increasing CD4 count threshold eligibility for antiretroviral therapy initiation on advanced HIV disease and tuberculosis prevalence and incidence in South Africa: an interrupted time series analysis

INTRODUCTION

We investigated the impact of increasing CD4 count eligibility for antiretroviral therapy (ART) initiation on advanced HIV disease (AHD) and tuberculosis (TB) prevalence and incidence among people living with HIV (PLHIV) in South Africa.

METHODS

We conducted an interrupted time series analysis with de-identified data of PLHIV aged ≥15 years initiating ART between April 2012 and February 2020 at 65 primary healthcare clinics in KwaZulu-Natal, South Africa. Outcomes included monthly proportions of new ART initiators presenting with AHD (CD4 count <200 cells/µL) and TB disease. We created a cohort of monthly ART initiators without TB and evaluated the cumulative incidence of TB within 12 months follow-up. We used segmented binomial regression models to estimate relative risks (RR) of outcomes, allowing for a step and slope change after expanding the ART initiation CD4 count eligibility from <350 to <500 cells/µL in January 2015 and following Universal Test and Treat (UTT) implementation in September 2016.

RESULTS

Among 209 984 participants, median age was 32 (range: 26-38), and 141 499 (67.4%) were female. After January 2015, the risk of AHD at initiation decreased in step by 25.0% (RR=0.750, 95% CI 0.688 to 0.812) and further reduced by 26.9% following UTT implementation (RR=0.731, 95% CI 0.681 to 0.781). The risk of TB at initiation also decreased in step by 27.6% after January 2015 (RR=0.724, 95% CI 0.651 to 0.797) and further decreased by 17.4% after UTT implementation (RR=0.826, 95% CI 0.711 to 0.941) but remained stable among initiators with AHD. Among the incidence cohort, we saw a step decrease in the risk of new TB by 31.4% (RR=0.686, 95% CI 0.465 to 0.907) following UTT implementation. Among the incidence cohort with AHD, there was weak evidence of a step decrease in the risk of new TB (RR=0.755, 95% CI 0.489 to 1.021), but the slope decreased by 9.7% per month (RR=0.903, 95% CI 0.872 to 0.934) following UTT implementation.

CONCLUSIONS

Our data support the added benefit of decreased TB co-burden with expanded ART access. Early diagnosis and immediate linkage to care should be prioritised among PLHIV.

Monitoring for advanced disease in the universal test and treat era: trends in CD4 count testing in South Africa

BACKGROUND

Under South Africa's Universal Test and Treat (UTT) policy, CD4 counts are no longer required to determine HIV treatment eligibility. However, CD4 count at presentation remains an important marker of disease progression. We assessed whether CD4 testing declined in the UTT era and, if so, by how much.

METHODS

We analysed CD4 count data from the National Health Laboratory Service (NHLS) National HIV Cohort and TIER.Net database for individuals in HIV care across five South African provinces. "First CD4 count" was defined as the first CD4 test recorded for each patient. In TIER.Net, "date of presentation" was the earliest date of HIV testing, CD4 measurement, or clinic visit. Trends in first CD4 testing volumes (2004-2018) were analyzed, with interrupted time-series analyses assessing the impact of UTT (September 2016).

RESULTS

Data included 5,274,218 (NHLS) and 2,265,557 (TIER.Net) individuals with a first CD4 count. In NHLS, first CD4 counts increased from 47,604 in 2004 to 383,705 in 2010 and then declined. Lower volumes were recorded in TIER.Net. Adjusting for prior trends, first CD4 counts increased slightly after UTT, by 32 individuals/day in NHLS (95% CI: - 6 to 61) and 88 individuals/day in TIER.Net (95% CI: 30 to 148). Among TIER.Net patients, the percentage with a CD4 count decreased by 4.3% (95% CI: - 5.2 to - 3.0%).

CONCLUSIONS

We found no major decline in CD4 testing at presentation following UTT, contrasting findings from resource-constrained settings with greater reliance on external donors.

The impact of tobacco smoking and smoking cessation on lung cancer and stroke incidence among people with HIV on antiretroviral therapy in South Africa: a simulation modeling study

INTRODUCTION

With declining HIV-related mortality, over 20% of people with HIV (PWH) in South Africa are now over age 50 years, and tobacco-related non-communicable disease burden is increasing. We quantified the impact of smoking and smoking cessation on lung cancer and stroke incidence among PWH in South Africa.

METHODS

Using a microsimulation model, we simulated 18 cohorts of initially virologically suppressed PWH over their lifetime, categorised by sex, initial age (35 years/45 years/55 years) and smoking status (current/former/never). Smoking status remains constant throughout the simulation; individuals with former smoking status quit at model start. PWH can disengage from HIV care and experience virological rebound. We modelled the relative risk of lung cancer for females (males) with current versus never smoking status as 16.69 (15.83), and for females (males) with former versus never smoking status as 1.99-8.80 (1.90-6.18), depending on age at cessation. Corresponding modelled relative risks of stroke were 1.79 (1.54) for current versus never smoking, and 1.00-1.29 (1.00-1.12) for former versus never smoking. We varied HIV-related and smoking-related parameters in sensitivity analyses.

RESULTS

Modelled female (male) PWH who stop smoking at age 45 years experience 61.3% (70.9%) and 35.6% (18.6%) lower cumulative lung cancer and stroke incidence over 25 years compared with people who continue smoking. The proportion alive and lung cancer-free or alive and stroke-free over 25 years would increase by 10.4 (9.5) or 10.5 (8.5) percentage points. In sensitivity analysis, smoking and smoking cessation have a greater impact on lung cancer and stroke cumulative incidence if competing HIV-related mortality risks are lower or if PWH experience higher lung cancer and stroke risk compared with people without HIV apart from smoking.

CONCLUSION

Smoking cessation could substantially reduce lung cancer and stroke risk among PWH in South Africa. To reduce the rising non-communicable disease burden among PWH, smoking cessation should become part of routine care of PWH.

Global trends in CD4 count measurement and distribution at first antiretroviral treatment initiation

BACKGROUND

While people with HIV (PWH) start antiretroviral treatment (ART) regardless of CD4 count, CD4 measurement remains crucial for detecting advanced HIV disease and evaluating ART programmes. We explored CD4 measurement (proportion of PWH with a CD4 result available) and prevalence of CD4 <200 cells/µL at ART initiation within the International epidemiology Databases to Evaluate AIDS (IeDEA) global collaboration.

METHODS

We included PWH at participating ART programmes who first initiated ART at age 15-80 years during 2005-2019. We described proportions of PWH (i) with CD4 (measured within 6 months before to 2 weeks after ART initiation); and (ii) among those with a CD4, with CD4 <200; by year of ART initiation and region.

RESULTS

We included 1,355,104 PWH from 42 countries in 7 regions; 63% were female. Median (interquartile range) age at ART initiation was 37 (31-44) in men and 32 (26-39) in women. CD4 measurement initially increased, or remained stable over time until around 2013, but then declined to low levels in some regions (Southern Africa, except South Africa: from 54 to 13%; East Africa 85 to 31%; Central Africa 72 to 20%; West Africa: 91 to 53%; and Latin America: 87 to 56%). Prevalence of CD4<200 declined over time in all regions, but plateaued after 2015 at ≥30%.

CONCLUSIONS

CD4 measurement has declined sharply in recent years, especially in sub-Saharan Africa. Among those with a CD4, the prevalence of CD4 <200 remains concerningly high. Scaling up CD4 testing and securing adequate funding are urgent priorities.

Immunologic, virologic and drug resistance outcomes in an HIV-infected prospective cohort on treatment in South Africa

BACKGROUND

In September 2016, South Africa introduced the Universal Test and Treat (UTT) programme to manage HIV infection. However, the development of drug resistance and sustaining viral suppression are challenges to the success of treatment programmes. This prospective observational study describes virologic, immunologic, and drug resistance profiles in a test and treat cohort in north-eastern South Africa.

METHODS

Five hundred and thirty-four HIV-1 positive antiretroviral naïve adults entering treatment programmes were enrolled between January 2016 and February 2018. Trends in CD4+ cell count, viral load, and drug resistance by examination of deep sequences were assessed at baseline and every three months, for 24 months.

RESULTS

Seventy-five percent were late initiators into ART (that is baseline CD4+ cell counts < 500 cells/microliter) and 16% were early initiators into ART and baseline CD4 was not available for 9%. Eleven percent (12/104) achieved immunological response after 6 months, 39.4% (41 /104) after 12 months, and 97.5% (101/104) after 24 months. Seventy-one percent (381/534) had baseline viral loads >1000 RNA copies/ml. Nine percent (22/246) achieved viral suppression after 3 months, 50% (122/246) after 6 months and 73.6% (181/246) after 12 months. A slower viral suppression was observed for males than females (p value = 0.012). A total of 45.6% (52/114) individuals had at least one drug resistance mutation (DRM) detected at >20% threshold in any of the time points, and the number increased to 55% (63/114) when minor variants were accounted for. Forty-eight percent (14/29) had drug resistance mutations at >5% threshold as early as 3 months into treatment.

CONCLUSION

The UNAIDS target of 95% viral suppression in individuals under treatment was not observed after 12 months of treatment, and this was less successful for males. Adherence and drug resistance monitoring could be beneficial for individuals harbouring resistant viruses early into treatment.

Tobacco smoking, smoking cessation and life expectancy among people with HIV on antiretroviral therapy in South Africa: a simulation modelling study

INTRODUCTION

As access to effective antiretroviral therapy (ART) has improved globally, tobacco-related illnesses, including cardiovascular disease, cancer and chronic respiratory conditions, account for a growing proportion of deaths among people with HIV (PWH). We estimated the impact of tobacco smoking and smoking cessation on life expectancy among PWH in South Africa.

METHODS

In a microsimulation model, we simulated 18 cohorts of PWH with virologic suppression, each homogenous by sex, initial age (35y/45y/55y) and smoking status (current/former/never). Input parameters were from data sources published between 2008 and 2022. We used South African data to estimate age-stratified mortality hazard ratios: 1.2-2.3 (females)/1.1-1.9 (males) for people with current versus never smoking status; and 1.0-1.3 (females)/1.0-1.5 (males) for people with former versus never smoking status, depending on age at cessation. We assumed smoking status remains unchanged during the simulation; people who formerly smoked quit at model start. Simulated PWH face a monthly probability of disengagement from care and virologic non-suppression. In sensitivity analysis, we varied smoking-associated and HIV-associated mortality risks. Additionally, we estimated the total life-years gained if a proportion of all virologically suppressed PWH stopped smoking.

RESULTS

Forty-five-year-old females/males with HIV with virologic suppression who smoke lose 5.3/3.7 life-years compared to PWH who never smoke. Smoking cessation at age 45y adds 3.4/2.4 life-years. Simulated PWH who continue smoking lose more life-years from smoking than from HIV (females, 5.3 vs. 3.0 life-years; males, 3.7 vs. 2.6 life-years). The impact of smoking and smoking cessation increase as smoking-associated mortality risks increase and HIV-associated mortality risks, including disengagement from care, decrease. Model results are most sensitive to the smoking-associated mortality hazard ratio; varying this parameter results in 1.0-5.1 life-years gained from cessation at age 45y. If 10-25% of virologically suppressed PWH aged 30-59y in South Africa stopped smoking now, 190,000-460,000 life-years would be gained.

CONCLUSIONS

Among virologically suppressed PWH in South Africa, tobacco smoking decreases life expectancy more than HIV. Integrating tobacco cessation interventions into HIV care, as endorsed by the World Health Organization, could substantially improve life expectancy.

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.

Sensitivity and specificity of CRP and symptom screening as tuberculosis screening tools among HIV-positive and negative outpatients at a primary healthcare facility in Lusaka, Zambia: a prospective cross-sectional study

OBJECTIVES

To evaluate the performance of point-of-care C-reactive protein (CRP) as a screening tool for tuberculosis (TB) using a threshold of 10 mg/L in both people living with HIV (PLHIV) and HIV-negative individuals and compare it to symptom screening using a composite reference for bacteriological confirmation of TB.

METHODS

Prospective cross-sectional study.

SETTING

A primary healthcare facility in Lusaka, Zambia.

PARTICIPANTS

Consecutive adults (≥18 years) presenting for routine outpatient healthcare were enrolled. Of the 816 individuals approached to participate in the study, 804 eligible consenting adults were enrolled into the study, of which 783 were included in the analysis.

PRIMARY OUTCOME MEASURES

Sensitivity, specificity, positive predictive value and negative predictive value (NPV) of CRP and symptom screening.

RESULTS

Overall, sensitivity of WHO-recommended four-symptom screen (W4SS) and CRP were 87.2% (80.0-92.5) and 86.6% (79.6-91.8) while specificity was 30.3% (26.7-34.1) and 34.8% (31.2-38.6), respectively. Among PLHIV, sensitivity of W4SS and CRP was 92.2% (81.1-97.8) and 94.8% (85.6-98.9) while specificity was 37.0% (31.3-43.0) and 27.5% (22.4-33.1), respectively. Among those with CD4≥350, the NPV for CRP was 100% (92.9-100). In the HIV negative, sensitivity of W4SS and CRP was 83.8% (73.4-91.3) and 80.3% (69.5-88.5) while specificity was 25.4% (20.9-30.2) and 40.5% (35.3-45.6), respectively. Parallel use of CRP and W4SS yielded a sensitivity and NPV of 100% (93.8-100) and 100% (91.6-100) among PLHIV and 93.3% (85.1-97.8) and 90.0% (78.2-96.7) among the HIV negatives, respectively.

CONCLUSION

Sensitivity and specificity of CRP were similar to symptom screening in HIV-positive outpatients. Independent use of CRP offered limited additional benefit in the HIV negative. CRP can independently accurately rule out TB in PLHIV with CD4≥350. Parallel use of CRP and W4SS improves sensitivity irrespective of HIV status and can accurately rule out TB in PLHIV, irrespective of CD4 count.

Tuberculosis-Associated Immune Reconstitution Inflammatory Syndrome-An Extempore Game of Misfiring with Defense Arsenals

The lethal combination involving TB and HIV, known as "syndemic" diseases, synergistically act upon one another to magnify the disease burden. Individuals on anti-retroviral therapy (ART) are at risk of developing TB-associated immune reconstitution inflammatory syndrome (TB-IRIS). The underlying inflammatory complication includes the rapid restoration of immune responses following ART, eventually leading to exaggerated inflammatory responses to MTB antigens. TB-IRIS continues to be a cause of morbidity and mortality among HIV/TB coinfected patients initiating ART, and although a significant quantum of knowledge has been acquired on the pathogenesis of IRIS, the underlying pathomechanisms and identification of a sensitive and specific diagnostic marker still remain a grey area of investigation. Here, we reviewed the latest research developments into IRIS immunopathogenesis, and outlined the modalities to prevent and manage strategies for better clinical and diagnostic outcomes for IRIS.

Early HIV treatment and survival over six years of observation in the ANRS 12249 Treatment as Prevention Trial

OBJECTIVES

Population-based universal test and treat (UTT) trials have shown an impact on population-level virological suppression. We followed the ANRS 12249 TasP trial population for 6 years to determine whether the intervention had longer-term survival benefits.

METHODS

The TasP trial was a cluster-randomized trial in South Africa from 2012 to 2016. All households were offered 6-monthly home-based HIV testing. Immediate antiretroviral therapy (ART) was offered through trial clinics to all people living with HIV (PLHIV) in intervention clusters and according to national guidelines in control clusters. After the trial, individuals attending the trial clinics were transferred to the public ART programme. Deaths were ascertained through annual demographic surveillance. Random-effects Poisson regression was used to estimate the effect of trial arm on mortality among (i) all PLHIV; (ii) PLHIV aware of their status and not on ART at trial entry; and (iii) PHLIV who started ART during the trial.

RESULTS

Mortality rates among PLHIV were 9.3/1000 and 10.4/1000 person-years in the control and intervention arms, respectively. There was no evidence that the intervention decreased mortality among all PLHIV [adjusted rate ratio (aRR) = 1.10, 95% confidence interval (CI) = 0.85-1.43, p = 0.46] or among PLHIV who were aware of their status but not on ART. Among individuals who initiated ART, the intervention decreased mortality during the trial (aRR = 0.49, 95% CI = 0.28-0.85, p = 0.01), but not after the trial ended.

CONCLUSIONS

The 'treat all' strategy reduced mortality among individuals who started ART but not among all PLHIV. To achieve maximum benefit of immediate ART, barriers to ART uptake and retention in care need to be addressed.

Characteristics and clinical outcomes of patients presenting with advanced HIV disease in the "treat all" era: a retrospective cohort study from rural Rwanda

Background

In 2016 Rwanda adopted “treat all” where all patients with HIV are immediately eligible for ART regardless of disease progression. Despite widespread availability of treatment, it is unknown whether presentation with advanced HIV persists.

Methods

We conducted a retrospective cohort among patients aged ≥ 15 who enrolled in care between July 2016 and July 2018 in three rural Rwandan districts. We estimated the prevalence of advanced HIV, defined as presenting with CD4 count < 200 cells/mm³ or WHO stage 3 or 4, and compared baseline characteristics of patients with and without advanced HIV. We compared cumulative incidences and time to events using Chi squared tests and Cox proportional hazards models, respectively, for (a) viral load tests; (b) viral suppression; (c) death; and (d) treatment failure (a composite of death, lost to follow up, or virologic failure).

Results

Among 957 patients, 105 (11.0%) presented with advanced HIV. These patients were significantly more likely to have low body mass index, come from Burera district, be older, and be identified through inpatient settings rather than through voluntary or prenatal testing. Patients with advanced HIV had significantly higher risks of death at 12-months (9.5% vs 1.5%, p < 0.001) and 18-months (10.5% vs 1.9%, p < 0.001) and significantly higher risk of treatment failure at 12-months (21.9% vs. 14.2%, p = 0.037). After adjusting for confounders, patients with advanced HIV had still higher rates of death (adjusted Hazard ratio [aHR] = 4.4, 95% CI: 1.9, 10.2, p < 0.001) and treatment failure (aHR = 1.7, 95% CI: 1.1, 2.5, p = 0.017), but no difference in viral load testing (aHR = 1.1, 95% CI: 0.8, 1.5, p = 0.442) or viral suppression (aHR = 1.0, 95% CI: 0.8, 1.4, p = 0.949). When allowing for the hazard ratio to vary over time, patients with advanced HIV experienced elevated rates of treatment failure in the first six of enrollment, but not after nine months.

Conclusion

Presenting with advanced HIV remains common and is still associated with poor patient outcomes. Sensitization of the community to the benefits of early ART initiation, identification of patients with advanced HIV, and holistic support programs for the first 6 months of treatment may be needed to improve outcomes.