Immune recovery among Romanian HIV/AIDS patients receiving darunavir/ritonavir or darunavir/cobicistat regimens in cART management: A three-year study

Approximately two-thirds of Romanian HIV patients were parenterally infected with the F subtype of HIV in early childhood. They are now in the context of immunological aging, with immunosuppression posing an additional challenge in developing the most effective and well-tolerated regimens. The risk of an improper immune recovery is higher in these patients than in newly diagnosed patients. The primary goal of this retrospective study was to conduct a comparative analysis of the immune recovery, measured at three time points, on 462 HIV-infected patients who were registered at the "Matei Balş National Institute of Infectious Diseases", Bucharest, Romania, between 2018 and 2021, as follows: darunavir (DRV) 600 mg plus ritonavir (RTV) 100 mg (twice daily) was given to 384 patients, while DRV 800 mg plus cobicistat (COBI) 150 mg was given to 78 patients (once daily). The immune response was assessed by counting T lymphocytes, CD4 count cells/mm³, and the CD4/CD8 lymphocyte count ratio. Additionally, the study assessed the relationship between the immune and virological responses to therapy. Using various statistical tests, the results revealed that the immune response is normal in both groups, but with a statistically significant difference (p < 0.05) for the DRV/c group. Statistical associations between RNA viral plasma load and immune response (CD4 count and CD4/CD8 ratio) were assessed at all three visits and showed an insignificant association for the first two time points; however, at the final visit, the outcomes changed and reached statistical significance for both groups.

Is immune recovery different depending on the use of integrase strand transfer inhibitor-, non-nucleoside reverse transcriptase- or boosted protease inhibitor-based regimens in antiretroviral-naive HIV-infected patients?

OBJECTIVES

To analyse whether integrase inhibitor (InSTI)-based regimens achieve better immunological recovery than NNRTI- or boosted PI (bPI)-based regimens as initial ART.

METHODS

In a retrospective analysis, we selected patients who initiated ART with two NRTIs plus an InSTI, an NNRTI or a bPI and maintained both the same 'third drug' and an HIV-RNA <50 copies/mL in ≥95% of determinations once undetectable viral load had been achieved. We compared CD4+ count, %CD4+ and CD4+/CD8+ ratio recovery over 2 years. Data were analysed using mixed-effects regression models for repeated measures.

RESULTS

Of the 836 patients included, 208, 481 and 147 initiated with InSTI, NNRTI and bPI, respectively. For CD4+, %CD4+ and CD4+/CD8+ two main slopes were identified: from month 0 to month 6, with the highest increments; and from month 6 to month 24, with smaller increases every semester. Although the patients on InSTI achieved undetectable viral load faster, for CD4+ and %CD4+ there were no differences in the slopes of change according to the third drug either for the first phase (P=0.137 and P=0.393, respectively) or from month 6 onwards (P=0.834 and P=0.159, respectively). The increase in CD4+/CD8+ was slightly higher for bPI compared with InSTI (difference of 0.0119, 95% CI 0.0020-0.0205; P=0.018), but clinically negligible. From month 6 onwards, no differences were found between treatment groups (P=0.176).

CONCLUSIONS

Immune restoration measured as CD4+ count, %CD4+ and CD4+/CD8+ increases was independent of the third antiretroviral drug class used when given with two NRTIs.

Cell-Associated HIV-1 Unspliced-to-Multiply-Spliced RNA Ratio at 12 Weeks of ART Predicts Immune Reconstitution on Therapy

Human immunodeficiency virus (HIV) infection is currently managed by antiretroviral drugs, which block virus replication and promote immune restoration. However, the latter effect is not universal, with a proportion of infected individuals failing to sufficiently reconstitute their immune function despite a successful virological response to antiretroviral therapy (ART).

Incomplete restoration of CD4⁺ T-cell counts on antiretroviral therapy (ART) is a major predictor of HIV-related morbidity and mortality. To understand the possible mechanisms behind this poor immunological response despite viral suppression, we longitudinally measured more than 50 virological and immunological biomarkers in a cohort of HIV-infected individuals at several time points during the first 96 weeks of virologically suppressive ART. No baseline virological or immunological marker was predictive of the degree of immune reconstitution. However, the cell-associated HIV-1 unspliced-to-multiply-spliced (US/MS) RNA ratio at 12 weeks of ART positively correlated with markers of CD4⁺ T-cell activation and apoptosis and negatively predicted both the absolute and relative CD4⁺ T-cell counts at 48 and 96 weeks. A higher US/MS RNA ratio may reflect the higher frequency of productively infected cells that could exert pressure on the immune system, contributing to persistent immune activation and apoptosis and subsequently to a poor immunological response to ART.

Immune recovery in HIV-1 infected patients with sustained viral suppression under long-term antiretroviral therapy in Ethiopia

BACKGROUND

There is very little data on long-term immune recovery responses in patients on suppressive antiretroviral therapy (ART) in the setting of sub-Saharan Africa (SSA). Thus, we sought to determine CD4+ T-cell, CD8+ T-cell and CD4/CD8 ratio responses in a cohort of HIV infected individuals on sustained suppressive ART followed up for more than a decade.

METHODS

The cohort comprised adult patients who started ART between 2001 and 2007 and followed for up to 14 years. Trends in median CD4+ T-cells, CD8+ T-cells and CD4/CD8 ratio were reviewed retrospectively. Poisson regression models were used to identify factors associated with achieving normalized T-cell biomarkers. Kaplan-Meier curves were used to estimate the probability of attaining normalized counts while on suppressive ART.

RESULTS

A total of 227 patients with a median duration of follow-up on ART of 12 (IQR: 10.5-13.0) years were included. CD4 cell count increased from baseline median of 138 cells (IQR: 70-202) to 555 cells (IQR: 417-830). CD4 cell increased continuously up until 5 years, after which it plateaued up until 14 years of follow up. Only 69.6% normalized their CD4 cell count within a median of 6.5 (IQR: 3.0-10.5) years. In addition, only 15.9% of the cohort were able to achieve the median reference CD4+ T-cell threshold count in Ethiopians (≈760 cells/μL). CD8+ T-cell counts increased initially until year 1, after which continuous decrease was ascertained. CD4/CD8 ratio trend revealed continuous increase throughout the course of ART, and increased from a median baseline of 0.14 (IQR: 0.09-0.22) to a median of 0.70 (IQR: 0.42-0.95). However, only 12.3% normalized their ratio (≥ 1.0) after a median of 11.5 years. In addition, only 8.8% of the cohort were able to achieve the median reference ratio of healthy Ethiopians.

CONCLUSION

Determination of both CD4+ and CD8+ T-cells, along with CD4/CD8 ratio is highly relevant in long-term follow-up of patients to assess immune recovery. Monitoring ratio levels may serve as a better biomarker risk for disease progression among patients on long-term ART. In addition, the findings emphasize the relevance of initiation of ART at the early stage of HIV-1 infection.

Risk Factors for Low CD4+ Count Recovery Despite Viral Suppression Among Participants Initiating Antiretroviral Treatment With CD4+ Counts > 500 Cells/mm3: Findings From the Strategic Timing of AntiRetroviral Therapy (START) Trial

BACKGROUND

Low CD4 recovery among HIV-positive individuals who achieve virologic suppression is common but has not been studied among individuals initiating treatment at CD4 counts of >500 cells/mm.

SETTING

United States, Africa, Asia, Europe and Israel, Australia, Latin America.

METHODS

Among participants randomized to immediate antiretroviral therapy (ART) in the Strategic Timing of AntiRetroviral Therapy trial, low CD4 recovery was defined as a CD4 increase of <50 cells/mm from baseline after 8 months despite viral load of ≤200 copies/mL. Risk factors for low recovery were investigated with logistic regression.

RESULTS

Low CD4 recovery was observed in 39.7% of participants. Male sex [odds ratio (OR), 1.53; P = 0.007], lower screening CD4 cell counts (OR, 1.09 per 100 fewer cells/mm; P = 0.004), higher baseline CD8 cell counts (OR, 1.05 per 100 more cells/mm; P < 0.001), and lower HIV RNA levels (OR, 1.93 per log10 decrease; P < 0.001) were associated with low CD4 recovery. D-dimer had a quadratic association with low CD4 recovery, with lowest odds occurring at 0.32 μg/mL. At lower HIV RNA levels, the odds of low CD4 recovery were elevated across the levels of screening CD4 count; but at higher HIV RNA levels, the odds of low CD4 recovery were higher among those with lower vs. higher screening CD4.

CONCLUSIONS

Low CD4 recovery is frequent among participants starting ART at high CD4 counts. Risk factors include male sex, lower screening CD4 cell counts, higher CD8 cell counts, and lower HIV RNA levels. More follow-up is required to determine the impact of low CD4 recovery on clinical outcomes.

Factors influencing harmonized health data collection, sharing and linkage in Denmark and Switzerland: A systematic review

INTRODUCTION

The digitalization of medicine has led to a considerable growth of heterogeneous health datasets, which could improve healthcare research if integrated into the clinical life cycle. This process requires, amongst other things, the harmonization of these datasets, which is a prerequisite to improve their quality, re-usability and interoperability. However, there is a wide range of factors that either hinder or favor the harmonized collection, sharing and linkage of health data.

OBJECTIVE

This systematic review aims to identify barriers and facilitators to health data harmonization-including data sharing and linkage-by a comparative analysis of studies from Denmark and Switzerland.

METHODS

Publications from PubMed, Web of Science, EMBASE and CINAHL involving cross-institutional or cross-border collection, sharing or linkage of health data from Denmark or Switzerland were searched to identify the reported barriers and facilitators to data harmonization.

RESULTS

Of the 345 projects included, 240 were single-country and 105 were multinational studies. Regarding national projects, a Swiss study reported on average more barriers and facilitators than a Danish study. Barriers and facilitators of a technical nature were most frequently reported.

CONCLUSION

This systematic review gathered evidence from Denmark and Switzerland on barriers and facilitators concerning data harmonization, sharing and linkage. Barriers and facilitators were strictly interrelated with the national context where projects were carried out. Structural changes, such as legislation implemented at the national level, were mirrored in the projects. This underlines the impact of national strategies in the field of health data. Our findings also suggest that more openness and clarity in the reporting of both barriers and facilitators to data harmonization constitute a key element to promote the successful management of new projects using health data and the implementation of proper policies in this field. Our study findings are thus meaningful beyond these two countries.

Determinants of Restoration of CD4 and CD8 Cell Counts and Their Ratio in HIV-1-Positive Individuals With Sustained Virological Suppression on Antiretroviral Therapy

BACKGROUND

An increasing number of HIV-positive individuals now start antiretroviral therapy (ART) with high CD4 cell counts. We investigated whether this makes restoration of CD4 and CD8 cell counts and the CD4:CD8 ratio during virologically suppressive ART to median levels seen in HIV-uninfected individuals more likely and whether restoration depends on gender, age, and other individual characteristics.

METHODS

We determined median and quartile reference values for CD4 and CD8 cell counts and their ratio using cross-sectional data from 2309 HIV-negative individuals. We used longitudinal measurements of 60,997 HIV-positive individuals from the Antiretroviral Therapy Cohort Collaboration in linear mixed-effects models.

RESULTS

When baseline CD4 cell counts were higher, higher long-term CD4 cell counts and CD4:CD8 ratios were reached. Highest long-term CD4 cell counts were observed in middle-aged individuals. During the first 2 years, median CD8 cell counts converged toward median reference values. However, changes were small thereafter and long-term CD8 cell count levels were higher than median reference values. Median 8-year CD8 cell counts were higher when ART was started with <250 CD4 cells/mm. Median CD4:CD8 trajectories did not reach median reference values, even when ART was started at 500 cells/mm.

DISCUSSION

Starting ART with a CD4 cell count of ≥500 cells/mm makes reaching median reference CD4 cell counts more likely. However, median CD4:CD8 ratio trajectories remained below the median levels of HIV-negative individuals because of persisting high CD8 cell counts. To what extent these subnormal immunological responses affect specific clinical endpoints requires further investigation.

CD4/CD8 ratio and CD8 counts predict CD4 response in HIV-1-infected drug naive and in patients on cART

Plasma HIV viral load is related to declining CD4 lymphocytes. The extent to which CD8 cells, in addition to RNA viral load, predict the depletion of CD4 cells is not well characterized so far. We examine if CD8 cell count is a prognostic factor for CD4 cell counts during an HIV infection.A longitudinal analysis is conducted using data from the Swiss HIV cohort study collected between January 2000 and October 2014. Linear mixed regression models were applied to observations from HIV-1-infected treatment naive patients (NAIVE) and cART-treated patients to predict the short-term evolution of CD4 cell counts. For each subgroup, it was quantified to which extent CD8 cell counts or CD4/CD8 ratios are prognostic factors for disease progression.In both subgroups, 2500 NAIVE and 8902 cART patients, past CD4 cells are positively (P < 0.0001) and past viral load is negatively (P < 0.0001) associated with the outcome. Including additionally past CD8 cell counts improves the fit significantly (P < 0.0001) and increases the marginal explained variation 31.7% to 40.7% for the NAIVE and from 44.1% to 50.7% for the cART group. The past CD4/CD8 ratio (instead of the past CD8 level) is positively associated with the outcome, increasing the explained variation further to 41.8% for NAIVE and 51.9% for cART.

CD4 Count Recovery After Initiation of Antiretroviral Therapy in Patients Infected With Human Immunodeficiency Virus

BACKGROUND

Prognosis for patients infected with human immunodeficiency virus (HIV) correlates with levels of CD4+ T cells. Initiation of antiretroviral therapy (ART) interrupts multiple points in the virus life cycle, causing an increase in CD4 cells. The rate at which the CD4 count recovers is highly variable and subject to influence by many factors.

METHODS

We performed a deidentified data review to determine factors influencing the rate of CD4 count recovery after ART initiation. The associations between the changes in CD4 count from baseline at 5 time points, and factors including age, race, weight, baseline CD4 count, baseline viral load, specific ART medications and various comorbidities, were evaluated with univariate and multivariate analyses, using t-test, analysis of variance and multiple regressions.

RESULTS

CD4 count continued to rise even up to 10 years after ART initiation, with the steepest increase in the first 3 months. High baseline viral load and low baseline CD4 count had the most consistent positive influence on CD4 count recovery rate across the 5 measured time points. Other factors that were significantly positively associated with CD4 recovery rate included younger baseline age, higher baseline weight and female gender.

CONCLUSIONS

CD4 counts in HIV positive patients who consistently take ART continue to increase out to at least 10 years. Patients with a more advanced HIV infection at baseline, as indicated by high viral loads or low CD4 counts, have a greater rate of CD4 count recovery after starting ART, possibly because their CD4 counts have more room for improvement.

Dynamic Perturbations of the T-Cell Receptor Repertoire in Chronic HIV Infection and following Antiretroviral Therapy

HIV infection profoundly affects many parameters of the immune system and ultimately leads to AIDS, yet which factors are most important for determining resistance, pathology, and response to antiretroviral treatment – and how best to monitor them – remain unclear. We develop a quantitative high-throughput sequencing pipeline to characterize the TCR repertoires of HIV-infected individuals before and after antiretroviral therapy, working from small, unfractionated samples of peripheral blood. This reveals the TCR repertoires of HIV⁺ individuals to be highly perturbed, with considerably reduced diversity as a small proportion of sequences are highly overrepresented. HIV also causes specific qualitative changes to the repertoire including an altered distribution of V gene usage, depletion of public TCR sequences, and disruption of TCR networks. Short-term antiretroviral therapy has little impact on most of the global damage to repertoire structure, but is accompanied by rapid changes in the abundance of many individual TCR sequences, decreases in abundance of the most common sequences, and decreases in the majority of HIV-associated CDR3 sequences. Thus, high-throughput repertoire sequencing of small blood samples that are easy to take, store, and process can shed light on various aspects of the T-cell immune compartment and stands to offer insights into patient stratification and immune reconstitution.

Timing of antiretroviral therapy initiation after diagnosis of recent human immunodeficiency virus infection and CD4(+) T-cell recovery

We retrospectively examined the timing of antiretroviral therapy (ART) initiation and CD4(+) T-cell recovery over 36 months among recent human immunodeficiency virus (HIV) infections using BED (HIV-1 subtypes B, E and D) immunoglobulin G capture enzyme immunoassay (BED-CEIA). Regardless of baseline CD4(+) counts, individuals (n = 393) who initiated ART >2 months after diagnosis had significantly decreased probability and rate of achieving CD4(+) counts ≥900 cells/μL or ≥600 cells/μL than those individuals (n = 135) who started ART earlier (≤2 months). But the mean CD4(+) counts in two groups converged after 30 months of treatment. Early ART initiation leads to accelerated CD4(+) recovery, but does not offer a long-term advantage in CD4(+) counts.

Management of HIV/AIDS in older patients-drug/drug interactions and adherence to antiretroviral therapy

Patients with human immunodeficiency virus (HIV) are living longer with their disease, as HIV has become a chronic illness managed with combination antiretroviral therapy (cART). This has led to an increasing number of patients greater than 50 years old living successfully with HIV. As the number of older adults with HIV has increased, there are special considerations for the management of HIV. Older adults with HIV must be monitored for drug side effects and toxicities. Their other non-HIV comorbidities should also be considered when choosing a cART regimen. Older adults with HIV have unique issues related to medication compliance. They are more likely than the younger HIV patients to have vision loss, cognitive impairment, and polypharmacy. They may have lower expectations of their overall health status. Depression and financial concerns, especially if they are on a fixed income, may also contribute to noncompliance in the aging HIV population.

Implementation and Operational Research: Effects of CD4 Monitoring Frequency on Clinical End Points in Clinically Stable HIV-Infected Patients With Viral Suppression

BACKGROUND

Current treatment guidelines for HIV infection recommend routine CD4 lymphocyte (CD4) count monitoring in patients with viral suppression. This may have a limited impact on influencing care as clinically meaningful CD4 decline rarely occurs during viral suppression.

METHODS

In a regional HIV observational cohort in the Asia-Pacific region, patients with viral suppression (2 consecutive viral loads <400 copies/mL) and a CD4 count ≥200 cells per microliter who had CD4 testing 6 monthly were analyzed. Main study end points were occurrence of 1 CD4 count <200 cells per microliter (single CD4 <200) and 2 CD4 counts <200 cells per microliter within a 6-month period (confirmed CD4 <200). A comparison of time with single and confirmed CD4 <200 with biannual or annual CD4 assessment was performed by generating a hypothetical group comprising the same patients with annual CD4 testing by removing every second CD4 count.

RESULTS

Among 1538 patients, the rate of single CD4 <200 was 3.45/100 patient-years and of confirmed CD4 <200 was 0.77/100 patient-years. During 5 years of viral suppression, patients with baseline CD4 200-249 cells per microliter were significantly more likely to experience confirmed CD4 <200 compared with patients with higher baseline CD4 [hazard ratio, 55.47 (95% confidence interval: 7.36 to 418.20), P < 0.001 versus baseline CD4 ≥500 cells/μL]. Cumulative probabilities of confirmed CD4 <200 was also higher in patients with baseline CD4 200-249 cells per microliter compared with patients with higher baseline CD4. There was no significant difference in time to confirmed CD4 <200 between biannual and annual CD4 measurement (P = 0.336).

CONCLUSIONS

Annual CD4 monitoring in virally suppressed HIV patients with a baseline CD4 ≥250 cells per microliter may be sufficient for clinical management.

CD4 Response Up to 5 Years After Combination Antiretroviral Therapy in Human Immunodeficiency Virus-Infected Patients in Latin America and the Caribbean

We describe CD4 counts at 6-month intervals for 5 years after combination antiretroviral therapy initiation among 12 879 antiretroviral-naive human immunodeficiency virus-infected adults from Latin America and the Caribbean. Median CD4 counts increased from 154 cells/mm³ at baseline (interquartile range [IQR], 60–251) to 413 cells/mm³ (IQR, 234–598) by year 5.

CD4 recovery on antiretroviral therapy is associated with decreased progression to liver disease among hepatitis C virus-infected injecting drug users

Background.  Human immunodeficiency virus (HIV) coinfection accelerates liver disease progression in individuals with chronic hepatitis C. We evaluated the associations of CD4, HIV RNA, and antiretroviral therapy (ART)-induced CD4 recovery with liver diagnoses in a prospective cohort of injecting drug users (IDUs). Methods.  We evaluated 383 coinfected IDUs in the Boston area, prospectively observed for a median of 1.8 years. Liver disease progression included the first occurrence of hepatocellular carcinoma, variceal bleeding, ascites, encephalopathy, or death due to hepatic failure. Multivariable-adjusted extended Cox models were specified to estimate hazard ratios (HRs) for comparisons of CD4, change in CD4 (from nadir), and HIV RNA with respect to liver disease progression events. Results.  Twenty-four persons experienced a liver disease progression event over 1155 person-years (2.1 per 100 person-years), including 20 deaths attributed to end-stage liver disease (1.7 per 100 person-years). CD4 at baseline and over follow-up strongly predicted liver disease progression (baseline CD4 <200 vs ≥200: HR = 5.23, 95% confidence interval [CI], 2.30-11.92; time-updated CD4 <200 vs ≥200: HR = 11.79, 95% CI, 4.47-31.07). Nadir CD4 was also a strong indicator (<100 vs ≥100: HR = 3.52, 95% CI, 1.54-8.06). A lack of CD4 recovery (failure to increase 100 cells over nadir) among ART initiators was associated with increased risk (HR = 7.69; 95% CI, 2.60-22.69). Human immunodeficiency virus RNA was not significantly associated with liver disease progression. Conclusions.  Impaired immune function was highly predictive of liver disease progression in this cohort of IDUs, and a lack of CD4 recovery on ART was associated with increased risk of progression to HCV-associated liver disease.

Long-term mortality in HIV-positive individuals virally suppressed for >3 years with incomplete CD4 recovery

BACKGROUND

Some human immunodeficiency virus (HIV)-infected individuals initiating combination antiretroviral therapy (cART) with low CD4 counts achieve viral suppression but not CD4 cell recovery. We aimed to identify (1) risk factors for failure to achieve CD4 count >200 cells/µL after 3 years of sustained viral suppression and (2) the association of the achieved CD4 count with subsequent mortality.

METHODS

We included treated HIV-infected adults from 2 large international HIV cohorts, who had viral suppression (≤500 HIV type 1 RNA copies/mL) for >3 years with CD4 count ≤200 cells/µL at start of the suppressed period. Logistic regression was used to identify risk factors for incomplete CD4 recovery (≤200 cells/µL) and Cox regression to identify associations with mortality.

RESULTS

Of 5550 eligible individuals, 835 (15%) did not reach a CD4 count >200 cells/µL after 3 years of suppression. Increasing age, lower initial CD4 count, male heterosexual and injection drug use transmission, cART initiation after 1998, and longer time from initiation of cART to start of the virally suppressed period were risk factors for not achieving a CD4 count >200 cells/µL. Individuals with CD4 ≤200 cells/µL after 3 years of viral suppression had substantially increased mortality (adjusted hazard ratio, 2.60; 95% confidence interval, 1.86-3.61) compared with those who achieved CD4 count >200 cells/µL. The increased mortality was seen across different patient groups and for all causes of death.

CONCLUSIONS

Virally suppressed HIV-positive individuals on cART who do not achieve a CD4 count >200 cells/µL have substantially increased long-term mortality.

Composition and function of T cell subpopulations are slow to change despite effective antiretroviral treatment of HIV disease

The ability to reconstitute a normal immune system with antiretroviral therapy in the setting of HIV infection remains uncertain. This study aimed to characterize quantitative and qualitative aspects of various T cell subpopulations that do not improve despite effective ART. CD4∶CD8 ratio was evaluated in HIV-infected subjects with viral loads >10,000 copies/µl (“non-controllers”, n = 42), those with undetectable viral loads on ART (“ART-suppressed”, n = 53), and HIV-uninfected subjects (n = 22). In addition, T cell phenotype and function were examined in 25 non-controllers, 18 ART-suppressed, and 7 HIV-uninfected subjects. CD4∶CD8 ratio in non-controllers, ART-suppressed, and HIV-uninfected subjects was 0.25, 0.48, and 1.95 respectively (P<0.0001 for all comparisons). The increased ratio in ART-suppressed compared to non-controllers was driven by an increase of CD4+ T cells, with no change in the expanded CD8+ T cell population. Expansion of differentiated (CD28−CD27−CD45RA+/−CCR7−) T cell subpopulations persisted despite ART and minimal changes were noted in naïve T cell frequencies over time. Increased number of CD8+CD28− T cells and increased CD8+ CMV-specific T cell responses were associated with a decreased CD4∶CD8 ratio. Measures of T cell function demonstrated persistence of high frequencies of CD8+ T cells producing IFN–γ. Lastly, though all CD8+ subpopulations demonstrated significantly lower Ki67 expression in ART-suppressed subjects, CD4+ T cell subpopulations did not consistently show this decrease, thus demonstrating different proliferative responses in the setting of T cell depletion. In summary, this study demonstrated that CD4∶CD8 ratios remained significantly decreased and naïve T cell numbers were slow to increase despite long-term viral suppression on ART. In addition, there is a evidence of differential regulation of the CD4+ and CD8+ T cell subpopulations, suggesting independent homeostatic regulation of the two compartments.

HIV and Menopause: A Systematic Review of the Effects of HIV Infection on Age at Menopause and the Effects of Menopause on Response to Antiretroviral Therapy

More than half of persons living with HIV infection in the United States (U.S.) will be ≥50 years of age by 2020, including postmenopausal women. We conducted a systematic literature review about the effects of (1) HIV infection on age at menopause and (2) menopause on antiretroviral therapy (ART) response, in order to inform optimal treatment strategies for menopausal women living with HIV infection. We used the Ovid Medline database from 1980 to 2012. We included studies that focused on HIV-infected persons, included postmenopausal women, and reported outcome data for either age at menopause or response to ART across menopause. We identified six original research articles for age at menopause and five for response to ART across menopause. Our review revealed that current data were conflicting and inconclusive; more rigorous studies are needed. Disentangling the effects of menopause requires well-designed studies with adequate numbers of HIV-infected and HIV-uninfected women, especially disproportionately affected women of color. Future studies should follow women from premenopause through menopause, use both surveys and laboratory measurements for menopause diagnoses, and control for confounders related to normal aging processes, in order to inform optimal clinical management for menopausal women living with HIV.

Prevalence of discordant immunologic and virologic responses in patients with AIDS under antiretroviral therapy in a specialized care center in Brazil

Some patients under antiretroviral therapy (ART) do not reach immune recovery when the viral load becomes undetectable. This is called discordant immunologic and virologic responses. Its prevalence varies between 8% and 24%. This study describes its prevalence and the characteristics of the affected subjects in the outpatient clinic of a Brazilian specialized-care center. Of 934 patients on ART, 536 had undetectable viral loads. Prevalence was 51/536 or 9% (95% confidence interval: 6.6% to 11.4%). Median age at the beginning of ART was 37 years (interquartile range - IQR: 31 to 45). Male gender and mixed race predominated (76.5% and 47.1% respectively). AIDS-defining illnesses were absent at the beginning of ART in 60.8%. Fifty-one percent were taking protease inhibitors, 43.2% Efavirenz and 5.8% both. Median time on ART was 36 months (IQR: 17-81 months). Irregular treatment was recorded for 21.6%. ART had been modified for 63% prior to the study, and 15.7% had used monotherapy or double therapy. Median CD4 count was 255 cells/mm³ (IQR: 200-284). Median viral load before ART was 4.7 log10 copies/mL (IQR: 4.5-5.2). Discordant responders were not different from AIDS patients in general, but there was a high frequency of multiple schedules of treatment.

Long-term complications in patients with poor immunological recovery despite virological successful HAART in Dutch ATHENA cohort

OBJECTIVE

We investigated the risk of AIDS and serious non-AIDS-defining diseases (non-ADDs) according to the degree of immunological recovery after 2 years of virological successful antiretroviral therapy (HAART).

DESIGN

Retrospective observational cohort study including HIV-infected patients treated with HAART resulting in viral suppression (<500 copies/ml).

METHODS

Patients were grouped according to their CD4 cell count after 2 years of HAART: CD4 cell count less than 200 cells/μl (group A), 200-350 cells/μl (group B), 351-500 cells/μl (group C) or more than 500 cells/μl (group D). Analysis was done to assess predictors for poor immunological recovery and the occurrence of a composite endpoint [death, AIDS, malignancies, liver cirrhosis and cardiovascular events (CVEs)], non-ADDs, CVEs and non-AIDS-defining malignancies (non-ADMs).

RESULTS

Three thousand and sixty-eight patients were included. Older age, lower CD4 cell nadir and lower plasma HIV-RNA at the start of HAART were independent predictors for a poor immunological recovery. The composite endpoint, non-ADDs and CVE were observed most frequently in group A (overall log rank, P < 0.0001, P = 0.002 and P = 0.01). In adjusted analyses, age was a strong independent predictor for all endpoints. Compared with group A, patients in group D had a lower risk for the composite endpoint [hazard ratio 0.54 (95% confidence interval [CI] 0.33-0.87]; patients in group B had a lower risk for CVEs [hazard ratio 0.34 (95% CI 0.14-0.86)].

CONCLUSION

Poor immunological recovery despite virological successful HAART is associated with a higher risk for overall morbidity and mortality and CVEs in particular. This study underlines the importance of starting HAART at higher CD4 cell counts, particularly in older patients.

Factors predicting discordant virological and immunological responses to antiretroviral therapy in HIV-1 clade C infected Zulu/Xhosa in South Africa

Factors predicting suboptimal CD4 cell recovery have been studied in HIV clade-B infected US and European populations. It is, however, uncertain to what extent these results are applicable to HIV clade-C infected African populations. Multivariate analysis using logistic regression and longitudinal analyses using mixed models were employed to assess the impact of age, gender, baseline CD4 cell count, hemoglobin, body mass index (BMI), tuberculosis and other opportunistic co-infections, and frequencies of regimen change on CD4 cell recovery at 12 and 30 months and on overtime change in CD4 cells among 442 virologically suppressed South Africans. Despite adequate virological response 37% (95% CI:32%–42%) and 83% (95% CI:79%–86%) of patients on antiretroviral therapy failed to restore CD4 cell counts ≥200 cells/mm³ after 12 and ≥500 cells/mm³ after 30 months, respectively, in this South African cohort. Critical risk factors for inadequate recovery were older age (p = 0.001) and nadir CD4 cell count at ART initiation (p<0.0001), while concurrent TB co-infection, BMI, baseline hemoglobin, gender and antiretroviral regimen were not significant risk factors. These data suggest that greater efforts are needed to identify and treat HAART-eligible patients prior to severe CD4 cell decline or achievement of advanced age.

Factors associated with paradoxical immune response to antiretroviral therapy in HIV infected patients: a case control study

Background

A paradoxical immunologic response (PIR) to Highly Active Antiretroviral Therapy (HAART), defined as viral suppression without CD4 cell-count improvement, has been reported in the literature as 8 to 42%, around 15% in most instances. The present study aims to determine, in a cohort of HIV infected patients in Brazil, what factors were independently associated with such a discordant response to HAART.

Methods

A case-control study (1:4) matched by gender was conducted among 934 HIV infected patients on HAART in Brazil. Cases: patients with PIR, defined as CD4 < 350 cells/mm³ (hazard ratio for AIDS or death of at least 8.5) and undetectable HIV viral load on HAART for at least one year. Controls: similar to cases, but with CD4 counts ≥ 350 cells/mm³. Eligibility criteria were applied. Data were collected from medical records using a standardized form. Variables were introduced in a hierarchical logistic regression model if a p-value < 0.1 was determined in a bivariate analysis.

Results

Among 934 patients, 39 cases and 160 controls were consecutively selected. Factors associated with PIR in the logistic regression model were: total time in use of HAART (OR 0.981; CI 95%: 0.96-0.99), nadir CD4-count (OR 0.985; CI 95%: 0.97-0.99), and time of undetectable HIV viral load (OR 0.969; CI 95%: 0.94-0.99).

Conclusions

PIR seems to be related to a delay in the management of immunodeficient patients, as shown by its negative association with nadir CD4-count. Strategies should be implemented to avoid such a delay and improve the adherence to HAART as a way to implement concordant responses.

Long-term immunological outcomes in treated HIV-infected individuals in high-income and low-middle income countries

PURPOSE OF REVIEW

To summarize the recent findings on long-term (at least 3-4 years) immunological responses to combination antiretroviral therapy (cART) and to compare and contrast the findings between cohorts from high-income and low-middle income countries (LMICs).

RECENT FINDINGS

Cohort studies from high-income settings suggest that a majority of treated HIV-infected patients who maintain suppressed HIV viremia experience a gradual increase in CD4 cell counts for several years to normal levels. However, those who start cART at CD4 cell counts less than 200 cells/μl (as opposed to CD4 cell counts>200 cells/μl) spend several more years below the safe CD4 cell count threshold of 500 cells/μl. Cohorts from LMICs also report persistent improvements in CD4+ cell counts over first 4-5 years of follow-up. However, low-CD4 cell counts (<200 cells/μl) at the start of cART, high early mortality, and loss to follow-up in LMICs settings suggest that the observed optimistic responses may be affected by survivorship bias and should be cautiously interpreted as the optimal, rather than an average, response in LMICs populations.

SUMMARY

LMICs cohorts report similar immunological responses to cART as high-income countries in first 4-5 years of follow-up. Sustaining success in these settings is dependent on timely access to first-line and future cART options, efforts to reduce loss to follow-up, and implementation of treatment guidelines. Cohorts from LMICs are encouraged to continue improving treatment programs and to continue reporting outcomes over the next decade, as surveillance for potential future blunting in responses.

Clinical predictors of immune reconstitution following combination antiretroviral therapy in patients from the Australian HIV Observational Database

Background

A small but significant number of patients do not achieve CD4 T-cell counts >500cells/µl despite years of suppressive cART. These patients remain at risk of AIDS and non-AIDS defining illnesses. The aim of this study was to identify clinical factors associated with CD4 T-cell recovery following long-term cART.

Methods

Patients with the following inclusion criteria were selected from the Australian HIV Observational Database (AHOD): cART as their first regimen initiated at CD4 T-cell count <500cells/µl, HIV RNA<500copies/ml after 6 months of cART and sustained for at least 12 months. The Cox proportional hazards model was used to identify determinants associated with time to achieve CD4 T-cell counts >500cells/µl and >200cells/µl.

Results

501 patients were eligible for inclusion from AHOD (n = 2853). The median (IQR) age and baseline CD4 T-cell counts were 39 (32–47) years and 236 (130–350) cells/µl, respectively. A major strength of this study is the long follow-up duration, median (IQR) = 6.5(3–10) years. Most patients (80%) achieved CD4 T-cell counts >500cells/µl, but in 8%, this took >5 years. Among the patients who failed to reach a CD4 T-cell count >500cells/µl, 16% received cART for >10 years. In a multivariate analysis, faster time to achieve a CD4 T-cell count >500cells/µl was associated with higher baseline CD4 T-cell counts (p<0.001), younger age (p = 0.019) and treatment initiation with a protease inhibitor (PI)-based regimen (vs. non-nucleoside reverse transcriptase inhibitor, NNRTI; p = 0.043). Factors associated with achieving CD4 T-cell counts >200cells/µl included higher baseline CD4 T-cell count (p<0.001), not having a prior AIDS-defining illness (p = 0.018) and higher baseline HIV RNA (p<0.001).

Conclusion

The time taken to achieve a CD4 T-cell count >500cells/µl despite long-term cART is prolonged in a subset of patients in AHOD. Starting cART early with a PI-based regimen (vs. NNRTI-based regimen) is associated with more rapid recovery of a CD4 T-cell count >500cells/µl.

A cost-effectiveness analysis of alternative HIV retesting strategies in sub-saharan Africa

BACKGROUND

Guidelines in sub-Saharan Africa on when HIV-seronegative persons should retest range from never to annually for lower-risk populations and from annually to every 3 months for high-risk populations.

METHODS

We designed a mathematical model to compare the cost-effectiveness of alternative HIV retesting frequencies. Cost of HIV counseling and testing, linkage to care, treatment costs, disease progression, and mortality, and HIV transmission are modeled for three hypothetical cohorts with posited annual HIV incidence of 0.8%, 1.3%, and 4.0%, respectively. The model compared costs, quality-adjusted life-years gained, and secondary infections averted from testing intervals ranging from 3 months to 30 years. Input parameters from sub-Saharan Africa were used and explored in sensitivity analyses.

RESULTS

Accounting for secondary infections averted, the most cost-effective testing frequency was every 7.5 years for 0.8% incidence, every 5 years for 1.3% incidence, and every 2 years for 4.0% incidence. Optimal testing strategies and their relative cost-effectiveness were most sensitive to assumptions about HIV counseling and testing and treatment costs, rates of CD4 decline, rates of HIV transmission, and whether tertiary infections averted were taken into account.

CONCLUSIONS

While higher risk populations merit more frequent HIV testing than low risk populations, regular retesting is beneficial even in low-risk populations. Our data demonstrate benefits of tailoring testing intervals to resource constraints and local HIV incidence rates.

Interruptions of cART limits CD4 T-cell recovery and increases the risk for opportunistic complications and death

BACKGROUND

A major goal of antiretroviral therapy (ART) for HIV-1-infected persons is the recovery of CD4 T lymphocytes, resulting in thorough protection against opportunistic complications. Interruptions of ART are still frequent. The long-term effect on CD4 T-cell recovery and clinical events remains unknown.

METHODS

Immunological and clinical endpoints were evaluated in 2491 participants of the Swiss HIV Cohort Study initiating ART during a mean follow-up of 7.1 years. Data were analysed in persons with treatment interruptions (n = 1271; group A), continuous ART, but intermittent HIV-1 RNA at least 1000 copies/ml (n = 469; group B) and continuous ART and HIV-1 RNA constantly less than 1000 copies/ml (n = 751; group C). Risk factors for low CD4 T-cell counts and clinical events were analysed using Cox proportional hazards models.

RESULTS

In groups A-C, CD4 T lymphocytes increased to a median of 427, 525 and 645 cells/μl at 8 years. In group A, 63.0 and 37.2% reached above 350 and 500 CD4 T cells/μl, whereas in group B 76.3 and 55.8% and in group C 87.3 and 68.0% reached these thresholds (P < 0.001). CD4 T-cell recovery directly depended on the cumulative duration of treatment interruptions. In addition, participants of group A had more Centers for Disease Control and Prevention B/C events, resulting in an increased risk of death. Major risk factors for not reaching CD4 T cells above 500 cells/μl included lower baseline CD4 T-cell count, higher age and hepatitis C virus co-infection.

CONCLUSION

In persons receiving continuous ART larger CD4 T-cell recovery and a reduced risk for opportunistic complications and death was observed. CD4 T-cell recovery was smaller in persons with treatment interruptions more than 6 months.

Long-term CD4+ T-cell count evolution after switching from regimens including HIV nucleoside reverse transcriptase inhibitors (NRTI) plus protease inhibitors to regimens containing NRTI plus non-NRTI or only NRTI

Background

Data regarding CD4+ recovery after switching from protease inhibitor (PI)-based regimens to regimens not containing PI are scarce.

Methods

Subjects with virological success on first-PI-regimens who switched to NNRTI therapy (NNRTI group) or to nucleoside reverse transcriptase (NRTI)-only (NRTI group) were studied. The effect of the switch on the ongoing CD4+ trend was assessed by two-phase linear regression (TPLR), allowing us to evaluate whether a change in the CD4+ trend (hinge) occurred and the time of its occurrence. Furthermore, we described the evolution of the frequencies in CD4-count classes across four relevant time-points (baseline, before and immediately after the switch, and last visit). Finally, we explored whether the CD4+ counts evolved differently in patients who switched to NNRTI or NRTI-only regimens by considering: the overall CD4+ trends, the time to CD4+≥ 500/mm³ after the switch, and the area-under-the-curve (AUC) of the CD4+ after the switch.

Results

Eight hundred and ninety-six patients, followed for a median of 2,121 days, were included. At TPLR, hinges occurred in 581/844 (68.9%), but in only 40/581 (6.9%) within a time interval (180 days) compatible with a possible relationship to the switch; furthermore, in 19/40 cases, CD4+ counts appeared to decrease after the hinges. In comparison with the NNRTI group, the NRTI group showed CD4+ count greater at baseline (P = 0.0234) and before the switch (P ≤ 0.0001), superior CD4+ T-cell increases after HAART was started, lower probability of not achieving CD4+ ≥ 500/mm³ (P = 0.0024), and, finally, no significant differences in the CD4+ T-cell AUC after the switch after adjusting for possible confounders (propensity score and pre-switch AUC). Persistence at CD4+ < 200/mm³ was observed in 34/435 (7.5%) patients, and a decrease below this level was found in only 10/259 (3.9%) with baseline CD4+ ≥ 350/mm³.

Conclusions

Switching from first-line PI to NNRTI- or NRTI-based regimens did not seem to impair CD4+ trend over long-term follow-up. Although the greater CD4+ increases in patients who switched to the NRTI-only regimen was due to higher CD4+ counts before the switch, several statistical analyses consistently showed that switching to this regimen did not damage the ongoing immune-reconstitution. Lastly, the observation that CD4+ T-cell counts remained low or decreased in the long term despite virological success merits further investigation.

Long-term CD4+ lymphocyte response following HAART initiation in a U.S. Military prospective cohort

Background

Among HIV-infected persons initiating highly active antiretroviral therapy (HAART), early CD4+ lymphocyte count increases are well described. However, whether CD4+ levels continue to increase or plateau after 4-6 years is controversial.

Methods

To address this question and identify other determinants of CD4+ response, we analyzed data for 1,846 persons from a prospective HIV military cohort study who initiated HAART, who had post-HAART CD4+ measurements, and for whom HIV seroconversion (SC) date was estimated.

Results

CD4+ count at HAART initiation was ≤ 200 cells/mm³ for 23%, 201-349 for 31%, 350-499 for 27%, and ≥500 for 19%. The first 6 months post-HAART, the greatest CD4+ increases (93-151 cells) occurred, with lesser increases (22-36 cells/year) through the first four years. Although CD4+ changes for the entire cohort were relatively flat thereafter, HIV viral load (VL) suppressors showed continued increases of 12-16 cells/year. In multivariate analysis adjusting for baseline CD4+ and post-HAART time interval, CD4+ responses were poorer in those with: longer time from HIV SC to HAART start, lower pre-HAART CD4+ nadir, higher pre-HAART VL, and clinical AIDS before HAART (P < 0.05).

Conclusions

Small but positive long-term increases in CD4+ count in virally suppressed patients were observed. CD4+ response to HAART is influenced by multiple factors including duration of preceding HIV infection, and optimized if treatment is started with virally suppressive therapy as early as possible.

Predicting the magnitude of short-term CD4+ T-cell recovery in HIV-infected patients during first-line highly active antiretroviral therapy

BACKGROUND

The extent of short-term CD4(+) T-cell recovery in patients tolerating first-line highly active antiretroviral therapy (HAART) and attaining undetectable HIV RNA levels is inadequately defined.

METHODS

We retrospectively analysed patients in four Italian cohorts who started HAART between January 1996 and September 2006. All patients had known HCV coinfection status, did not modify the regimen for 6 months and had <50 HIV RNA copies/ml at the end of the sixth month.

RESULTS

The analysis involved 1,488 patients (1,096 males, 73.7%) with a median age of 43 years (interquartile range [IQR] 39-49); 435 (29.2%) were positive for HCV, 71 (4.8%) were positive for hepatitis B surface antigen (HBsAg) and 76 (5.1%) had experienced a previous AIDS-defining event. At baseline, patient CD4(+) T-cell counts were 226 cells/microl (IQR 99-332), CD4(+) T-cell percentages were 14.7% (IQR 8.7-21.2) and HIV RNA levels were 4.91 log(10) copies/ml (IQR 4.38-5.34). Overall, 24-week CD4(+) T-cell recovery was 144 cells/microl (IQR 70-240). At multivariable analysis, T-cell recovery was positively related to the use of a boosted protease inhibitor (P<0.0001) or thymidine analogues (P<0.0001), baseline HIV RNA levels (P<0.0001), the baseline percentage of CD4(+) T-cells (P<0.0001) and the absence of HCV coinfection (P=0.006). Age, gender, baseline CD4(+)/CD8(+) T-cell ratio and a history of AIDS-defining events had no independent effect on CD4(+) T-cell recovery.

CONCLUSIONS

Among HIV-infected patients tolerating first-line HAART and with undetectable HIV RNA after 6 months, CD4(+) T-cell recovery is significantly greater in those without HCV coinfection, with a high baseline viral load, a high baseline percentage of CD4(+) T-cells and in those treated with a boosted protease inhibitor.

Outcomes of highly active antiretroviral therapy in the context of universal access to healthcare: the U.S. Military HIV Natural History Study

Background

To examine the outcomes of highly-active antiretroviral therapy (HAART) for individuals with free access to healthcare, we evaluated 2327 patients in a cohort study composed of military personnel and beneficiaries with HIV infection who initiated HAART from 1996 to the end of 2007.

Methods

Outcomes analyzed were virologic suppression (VS) and failure (VF), CD4 count changes, AIDS and death. VF was defined as never suppressing or having at least one rebound event. Multivariate (MV) analyses stratified by the HAART initiation year (before or after 2000) were performed to identify risk factors associated with these outcomes.

Results

Among patients who started HAART after 2000, 81% had VS at 1 year (N = 1,759), 85% at 5 years (N = 1,061), and 82% at 8 years (N = 735). Five years post-HAART, the median CD4 increase was 247 cells/ml and 34% experienced VF. AIDS and mortality rates at 5 years were 2% and 0.3%, respectively. In a MV model adjusted for known risk factors associated with treatment response, being on active duty (versus retired) at HAART initiation was associated with a decreased risk of AIDS (HR = 0.6, 95% CI 0.4-1.0) and mortality (0.6, 0.3-0.9), an increased probability of CD4 increase ≥ 50% (1.2, 1.0-1.4), but was not significant for VF.

Conclusions

In this observational cohort, VS rates approach those described in clinical trials. Initiating HAART on active duty was associated with even better outcomes. These findings support the notion that free access to healthcare likely improves the response to HAART thereby reducing HIV-related morbidity and mortality.

Prognosis of patients treated with cART from 36 months after initiation, according to current and previous CD4 cell count and plasma HIV-1 RNA measurements

OBJECTIVES

CD4 cell count and plasma viral load are well known predictors of AIDS and mortality in HIV-1-infected patients treated with combination antiretroviral therapy (cART). This study investigated, in patients treated for at least 3 years, the respective prognostic importance of values measured at cART initiation, and 6 and 36 months later, for AIDS and death.

METHODS

Patients from 15 HIV cohorts included in the ART Cohort Collaboration, aged at least 16 years, antiretroviral-naive when they started cART and followed for at least 36 months after start of cART were eligible.

RESULTS

Among 14 208 patients, the median CD4 cell counts at 0, 6 and 36 months were 210, 320 and 450 cells/microl, respectively, and 78% of patients achieved viral load less than 500 copies/ml at 6 months. In models adjusted for characteristics at cART initiation and for values at all time points, values at 36 months were the strongest predictors of subsequent rates of AIDS and death. Although CD4 cell count and viral load at cART initiation were no longer prognostic of AIDS or of death after 36 months, viral load at 6 months and change in CD4 cell count from 6 to 36 months were prognostic for rates of AIDS from 36 months.

CONCLUSIONS

Although current values of CD4 cell count and HIV-1 RNA are the most important prognostic factors for subsequent AIDS and death rates in HIV-1-infected patients treated with cART, changes in CD4 cell count from 6 to 36 months and the value of 6-month HIV-1 RNA are also prognostic for AIDS.

Development and evaluation of a clinical algorithm to monitor patients on antiretrovirals in resource-limited settings using adherence, clinical and CD4 cell count criteria

Background

Routine viral load monitoring of patients on antiretroviral therapy (ART) is not affordable in most resource-limited settings.

Methods

A cross-sectional study of 496 Ugandans established on ART was performed at the Infectious Diseases Institute, Kampala, Uganda. Adherence, clinical and laboratory parameters were assessed for their relationship with viral failure by multivariate logistic regression. A clinical algorithm using targeted viral load testing was constructed to identify patients for second-line ART. This algorithm was compared with the World Health Organization (WHO) guidelines, which use clinical and immunological criteria to identify failure in the absence of viral load testing.

Results

Forty-nine (10%) had a viral load of >400 copies/mL and 39 (8%) had a viral load of >1000 copies/mL. An algorithm combining adherence failure (interruption >2 days) and CD4 failure (30% fall from peak) had a sensitivity of 67% for a viral load of >1000 copies/mL, a specificity of 82%, and identified 22% of patients for viral load testing. Sensitivity of the WHO-based algorithm was 31%, specificity was 87%, and would result in 14% of those with viral suppression (<400 copies/mL) being switched inappropriately to second-line ART.

Conclusion

Algorithms using adherence, clinical and CD4 criteria may better allocate viral load testing, reduce the number of patients continued on failing ART, and limit the development of resistance.