Impact of hepatitis C virus coinfection on immune restoration during successful antiretroviral therapy in chronic human immunodeficiency virus type 1 disease

Impact of hepatitis C cure on risk of mortality and morbidity in people with HIV after antiretroviral therapy initiation

OBJECTIVE

Hepatitis C virus (HCV) co-infection is associated with increased morbidity and mortality in people with HIV (PWH). Sustained virological response (SVR) decreases the risk of HCV-associated morbidity. We compared mortality, risk of AIDS-defining events, and non-AIDS nonliver (NANL) cancers between HCV-co-infected PWH who reached SVR and mono-infected PWH.

DESIGN

Adult PWH from 21 cohorts in Europe and North America that collected HCV treatment data were eligible if they were HCV-free at the time of ART initiation.

METHODS

Up to 10 mono-infected PWH were matched (on age, sex, date of ART start, HIV acquisition route, and being followed at the time of SVR) to each HCV-co-infected PWH who reached SVR. Cox models were used to estimate relative hazards (hazard ratio) of all-cause mortality, AIDS-defining events, and NANL cancers after adjustment.

RESULTS

Among 62 495 PWH, 2756 acquired HCV, of whom 649 reached SVR. For 582 of these, at least one mono-infected PWH could be matched, producing a total of 5062 mono-infected PWH. The estimated hazard ratios comparing HCV-co-infected PWH who reached SVR with mono-infected PWH were 0.29 [95% confidence interval (CI) 0.12-0.73] for mortality, 0.85 [0.42-1.74] for AIDS-defining events, and 1.21 [0.86-1.72] for NANL cancer.

CONCLUSION

PWH who reached SVR a short time after HCV acquisition were not at higher risk of overall mortality compared with mono-infected PWH. However, the apparent higher risk of NANL cancers in HCV-co-infected PWH who reached SVR after a DAA-based treatment compared with mono-infected PWH, though compatible with a null association, suggests a need for monitoring of those events following SVR.

Influence of Hepatitis C virus coinfection on immune reconstitution in HIV subjects

Despite successful HIV suppression by antiretroviral treatment (ART), immune activation may persist in HIV patients, contributing to an impaired immunological reconstitution and disease progression. Information regarding Hepatitis C virus (HCV) coinfection as a factor that accounts for immune activation in HIV subjects remains unclear. Furthermore, most studies have been carried out considering HIV/HCV patients as a whole, without taking into account the presence or absence of liver damage. Therefore, it is unknown if HCV and/or its liver-related disease could act as two independent factors contributing to the immune activation. In this study, we investigated the presence of immune activation in a cohort of 50 HIV/HCV patients by measuring cytokine levels, CD4⁺ T-cell counts and CD4/CD8 ratios. Six patient groups were defined according to HIV viral load, HCV status, and liver disease to assess the impact of each of these factors on immune activation and reconstitution in HIV/HCV patients. Only subjects with controlled HIV infection and cleared HCV displayed immunological parameters within normal ranges. The mere presence of HCV contributes to immune activation leading to an inappropriate immunological reconstitution. This state exacerbates in the presence of HCV-associated liver disease. Our results suggest that ART is not enough to suppress immune activation in the context of HIV/HCV coinfection, since both HCV and its liver-related disease would contribute to the immune activation. Given that immune activation worsens immunological reconstitution and clinical status, these results support the priority of HCV treatment in HIV/HCV patients and suggest the monitoring of their liver status.

Safety of monitoring antiretroviral therapy response in HIV-1 infection using CD4+ T cell count at long-term intervals

The latest Brazilian guideline recommended the reduction of routine CD4+ T cell counts for the monitoring of patients with human immunodeficiency virus type 1 (HIV-1) under combination antiretroviral therapy (cART). The aim of this study was to evaluate the safety of monitoring response to cART in HIV-1 infection using routine viral load at shorter intervals and CD4+ T cell count at longer intervals. CD4+ T cell counts and HIV-1 viral load were evaluated in 1,906 HIV-1-infected patients under cART during a three-year follow-up. Patients were stratified as sustained, non-sustained and non-responders. The proportion of patients who showed a CD4+ T > 350cells/µL at study entry among those with sustained, non-sustained and non-responders to cART and who remained with values above this threshold during follow-up was 94.1%, 81.8% and 71.9%, respectively. HIV-1-infected patients who are sustained virologic responders and have initial CD4+ T cell counts > 350cells/µL showed a higher chance of maintaining the counts of these cells above this threshold during follow-up than those presenting CD4+ T ≤ 350cells/µL (OR = 39.9; 95%CI: 26.5-60.2; p < 0.001). This study showed that HIV-1-infected patients who had sustained virologic response and initial CD4+ T > 350cells/µL were more likely to maintain CD4+ T cell counts above this threshold during the next three-year follow-up. This result underscores that the evaluation of CD4+ T cell counts in longer intervals does not impair the safety of monitoring cART response when routine viral load assessment is performed in HIV-1-infected patients with sustained virologic response.

Long-term follow-up of elite controllers: Higher risk of complications with HCV coinfection, no association with HIV disease progression

To estimate the effect of hepatitis C virus (HCV) coinfection on the development of complications and progression of human immunodeficiency virus (HIV) disease among HIV-infected elite controllers.Single-center retrospective cohort. Kaplan-Meier methods, prevalence ratios, and Cox proportional-hazards models were used.In all, 55 HIV-infected elite controllers were included in this study. Among them, 45% were HIV/HCV coinfected and 55% were HIV mono-infected. Median follow-up time for the cohort was 11 years. Twenty-five patients experienced a complication and 16 lost elite controller status during the study period. HCV coinfected patients were 4.78 times (95% confidence interval 1.50-15.28) more likely to develop complications compared with HIV mono-infected patients. There was no association between HCV coinfection status and loss of elite control (hazard ratio 0.75, 95% confidence interval 0.27-2.06).Hepatitis C virus coinfection was significantly associated with the risk of complications even after controlling for sex, injecting drug use, and older age. HCV coinfected patients had higher levels of cellular activation while also having similar levels of lipopolysaccharide and soluble CD14. HCV coinfection was not associated with loss of elite controller status. Taken together, this suggests that HCV coinfection does not directly affect HIV replication dynamics or natural history, but that it may act synergistically with HIV to produce a greater number of associated complications. Continued follow-up will be needed to determine whether HCV cure through the use of direct-acting antivirals among HIV/HCV coinfected elite controllers will make the risk for complications among these patients similar to their HIV mono-infected counterparts.

Factors associated with long-term CD4 cell recovery in HIV-infected patients on successful antiretroviral therapy

OBJECTIVES

The aim of the study was to study the factors associated with immunological recovery in HIV-infected patients with suppressed viral load.

METHODS

Nadir and current CD4 cell counts were recorded in 821 patients, as well as many demographic, epidemiological, lifestyle, clinical, therapeutic, genetic, laboratory, liver fibrosis and viral hepatitis parameters.

RESULTS

The median age of the patients was 44.4 years [interquartile range (IQR) 40.3-48.0 years], the median time since HIV diagnosis was 15.3 years (IQR 10.5-18.9 years), the median time of suppressed viral load was 7.0 years (IQR 4.0-10.0 years) and the median time on the current antiretroviral regimen was 2.8 years (IQR 1.4-4.7 years). The median nadir and current CD4 counts were 193.0 (IQR 84.0-301.0) and 522.0 (IQR 361.0-760) cells/μL, respectively, separated by a median period of 10.2 years (IQR 5.9-12.9 years). The median CD4 count gain during follow-up was 317.0 (IQR 173.0-508.0) cells/μL. Many variables were associated with CD4 cell gains in univariate analyses, including age, gender, epidemiology, prior clinical conditions, fibrosis stage, transient elastometry, aspartate aminotransferase (AST), nadir CD4 count and hepatitis B and C virus infections and genotypes, as well as the durations of follow-up since nadir CD4 count, overall antiretroviral treatment, current antiretroviral regimen, protease inhibitor therapy and suppression of viral load. Multivariate analysis revealed that longer duration of HIV suppression (P < 0.0001), more advanced clinical Centers for Disease Control and Prevention (CDC) stages (P < 0.0001), younger age (P = 0.0003), hepatitis C virus genotypes 1 and 4 (P = 0.003), sexual acquisition of HIV (P = 0.004), and lower transient elastometry values (P = 0.03) were independent predictors of CD4 cell gains. Overall, the model accounted for 14.2% of the variability in CD4 count.

CONCLUSIONS

In addition to the duration of HIV suppression, HIV-related diseases, HIV epidemiology, age, hepatitis C virus genotypes, and liver fibrosis were independently associated with long-term immunological recovery.

Coinfection by Hepatitis C Is Strongly Associated with Abnormal CD4/CD8 Ratio in HIV Patients under Stable ART in Salvador, Brazil

Proper immune restoration (CD4 count >500 and normal CD4/8 ratio) is reached only by a fraction of HIV patients, despite stable viral suppression. Methods. We present a case-control study to compare HIV patients with viral suppression >1 year, according to immune restoration pattern: adequate response (AR) defined by CD4 > 500 cells/mm³ and CD4/8 ratio >1; partial response (PR = patients with CD4 > 500, but CD4/8 ratio <1); inadequate response (IR = CD4 < 500 cells). Results. We evaluated 293 consecutive patients (89 AR, 112 PR, and 92 IR), 70% males. Male gender (p < 0.01), lower mean CD4 nadir (p < 0.001), higher baseline VL (p = 0.01), previous diagnosis of Tb (p = 0.03), or HCV (p < 0.01) was associated with IR. Likelihood of AR/PR was similar regardless of gender, after adjusting for nadir CD4+ cells count. Longer time under suppressive ART was also associated with a greater chance of AR, but logistic regression identified coinfection by HCV as the main factor associated with abnormal CD4/CD8 ratio. Conclusion. Early initiation of ART and longer time since first undetectable PVL were predictors of AR. Previous HCV diagnosis significantly increases the risk of abnormal CD4/CD8 ratio.

Effect of hepatitis C virus on immunological and virological responses in HIV-infected patients initiating highly active antiretroviral therapy: a meta-analysis

Co-infection of human immunodeficiency virus (HIV) with hepatitis C virus (HCV) is rather common. In the era of highly active antiretroviral therapy (HAART), viral hepatitis could result in adverse outcomes in HIV+ patients. The current meta-analysis aims to evaluate the impact of HCV on immunological and virological responses after HAART initiation in HIV/HCV co-infected individuals by synthesizing the existing scientific evidence. A comprehensive search of electronic databases was performed. Eligible studies were analysed using univariate and multivariate meta-analytic methods. Totally, 21 studies involving 22533 individuals were eligible. The estimated summary difference in CD4 cell counts increase between HIV and HIV/HCV co-infected subjects after 3-12 months on HAART was 34.86 cells/mm(3) [95% confidence interval (CI): 16.82-52.89]. The difference was more prominent in patients with baseline CD4 counts below 350 cells/mm(3) (38.97, 95% CI: 20.00-57.93) and attenuated 2 years later (13.43, 95% CI: 0.83-26.04). The analysis of ratio measures yielded similar findings. The virological control remained unaffected by the presence of HCV (adjusted Hazard Ratio for co-infected patients vs those with HIV alone: 0.99, 95% CI: 0.91-1.07). The bivariate meta-analytic method confirmed the results of the univariate approaches. This meta-analysis supports the adverse effect of HCV on immune recovery of HIV+ patients initiating HAART, especially of those with initially impaired immunologic status. Although this effect diminishes over time, early administration of HAART in the setting of co-infection seems to be justified.

Immune restoration in human immunodeficiency virus and hepatitis C virus coinfected patients after highly active antiretroviral therapy

Objective

To evaluate the influence of hepatitis C virus on immunological and virological responses after highly active antiretroviral therapy initiation in human immunodeficiency virus/hepatitis C virus coinfected patients compared to monoinfected human immunodeficiency virus-infected patients.

Methods

The study enrolled 65 human immunodeficiency virus-1-infected subjects who initiated highly active antiretroviral therapy and attended follow-up visits over 48 weeks from 2008 to 2010. They were grouped based on hepatitis C virus-RNA results. Virological and immunological responses were monitored at baseline and at the end of weeks 12, 24, 36, and 48.

Results

There were 35 human immunodeficiency virus monoinfected and 30 human immunodeficiency virus/hepatitis C virus coinfected patients. In the present study human immunodeficiency virus/hepatitis C virus coinfection did not seem to influence CD4 T-lymphocytes recovery. There was no difference between the curves of CD4 T-lymphocytes raise of coinfected and monoinfected groups.

Conclusion

This prospective study confirms that hepatitis C virus infection does not seem to be associated with impaired CD4 T-lymphocytes recovery after HAART.

Chronic immune activation and decreased CD4 cell counts associated with hepatitis C infection in HIV-1 natural viral suppressors

We have established a cohort of natural viral suppressors (NVS) who can suppress HIV-1 replication to less than 400 copies/ml in the absence of therapy (similar to Elite Controllers/Elite Suppressors). Of the 59 patients currently in the NVS cohort, 45.8% have chronic hepatitis C virus (HCV) infection, thereby presenting a unique opportunity to study immune activation and the interaction between HCV and HIV. NVS with chronic HCV infection had elevated levels of immune activation (CD38-positive HLA-DR-positive CD8 cells) compared to NVS without chronic HCV (P = 0.004). The increased levels of immune activation were not associated with sex, HLA B57 status, or injection drug use use. NVS patients with chronic HCV had lower mean CD4 cell counts, CD4 percentage, and CD4/CD8 ratios than NVS without chronic HCV infection (P = 0.038, P = 0.008, and P = 0.048, respectively). The difference in CD4 cell count appeared to occur early in HIV infection with no difference observed in CD4 slopes between groups. Among all NVS, there was a direct correlation between mean CD4 cell count, mean CD4 percentage, and mean CD4/CD8 ratio with percentage of CD38 HLA-DR CD8 cells (P = 0.0018; P = 0.0069; and P = 0.0014, respectively). This study suggests a relationship between HCV infection, immune activation, and CD4 cell counts in the NVS, with chronic HCV infection associated with lower CD4 cell counts and higher levels of immune activation. Further studies are needed to determine if successful HCV treatment lowers immune activation levels and/or increases CD4 cell counts in these patients.

Virological effectiveness and CD4+ T-cell increase over early and late courses in HIV infected patients on antiretroviral therapy: focus on HCV and anchor class received

Background

The aim of this study was to explore the effects of HCV co-infection on virological effectiveness and on CD4+ T-cell recovery in patients with an early and sustained virological response after HAART.

Methods

We performed a longitudinal analysis of 3,262 patients from the MASTER cohort, who started HAART from 2000 to 2008. Patients were stratified into 6 groups by HCV status and type of anchor class. The early virological outcome was the achievement of HIV RNA <500 copies/ml 4–8 months after HAART initiation. Time to virological response was also evaluated by Kaplan-Meier analysis. The main outcome measure of early immunological response was the achievement of CD4+ T-cell increase by ≥100/mm³ from baseline to month 4–8 in virological responder patients. Late immunological outcome was absolute variation of CD4+ T-cell count with respect to baseline up to month 24. Multivariable analysis (ANCOVA) investigated predictors for this outcome.

Results

The early virological response was higher in HCV Ab-negative than HCV Ab-positive patients prescribed PI/r (92.2% versus 88%; p = 0.01) or NNRTI (88.5% versus 84.7%; p = 0.06). HCV Ab-positive serostatus was a significant predictor of a delayed virological suppression independently from other variables, including types of anchor class. Reactivity for HCV antibodies was associated with a lower probability of obtaining ≥100/mm³ CD4+ increase within 8 months from HAART initiation in patients treated with PI/r (62.2% among HCV Ab-positive patients versus 70.9% among HCV Ab-negative patients; p = 0.003) and NNRTI (63.7% versus 74.7%; p < 0.001). Regarding late CD4+ increase, positive HCV Ab appeared to impair immune reconstitution in terms of absolute CD4+ T-cell count increase both in patients treated with PI/r (p = 0.013) and in those treated with NNRTI (p = 0.002). This was confirmed at a multivariable analysis up to 12 months of follow-up.

Conclusions

In this large cohort, HCV Ab reactivity was associated with an inferior virological outcome and an independent association between HCV Ab-positivity and smaller CD4+ increase was evident up to 12 months of follow-up. Although the difference in CD4+ T-cell count was modest, a stricter follow-up and optimization of HAART strategy appear to be important in HIV patients co-infected by HCV. Moreover, our data support anti-HCV treatment leading to HCV eradication as a means to facilitate the achievement of the viro-immunological goals of HAART.

Immune reconstitution under antiretroviral therapy: the new challenge in HIV-1 infection

Although highly active antiretroviral therapy has enabled constant progress in reducing HIV-1 replication, in some patients who are "aviremic" during treatment, the problem of insufficient immune restoration remains, and this exposes them to the risk of immune deficiency-associated pathologies. Various mechanisms may combine and account for this impaired immunologic response to treatment. A first possible mechanism is immune activation, which may be because of residual HIV production, microbial translocation, co-infections, immunosenescence, or lymphopenia per se. A second mechanism is ongoing HIV replication. Finally, deficient thymus output, sex, and genetic polymorphism influencing apoptosis may impair immune reconstitution. In this review we will discuss the tools at our disposal to identify the various mechanisms at work in a given patient and the specific therapeutic strategies we could propose based on this etiologic diagnosis.

Hepatitis C virus coinfection does not affect CD4 restoration in HIV-infected patients after initiation of antiretroviral therapy

There are conflicting data regarding the influence of hepatitis C virus (HCV) infection on the immune restoration experienced by HIV-infected patients who receive highly active antiretroviral therapy (HAART). In this multicenter, retrospective, longitudinal study, CD4 restoration was assessed according to HCV status in treatment-naive HIV-infected patients within 3 years of HAART. Only patients with persistent HIV suppression were included. Factors predicting CD4 gains were analyzed with multivariate linear regression. Out of 322 patients included 139 had positive HCV-RNA and 183 were only HIV infected. HCV-HIV-coinfected patients were older, more often ex-intravenous drug users (IVDU), and had less advanced HIV infection. Baseline CD4 count [OR -0.21 [95% CI (-0.34)-(-0.04)]; p = 0.01] and male sex [OR -0.19 [95% CI (-191.12)-(-10.87)]; p = 0.03] predicted smaller increments in absolute CD4 counts, and higher baseline CD4% [OR -0.38 [95% CI (-0.39)-(-0.21)]; p < 0.0001] and older age [OR -0.12 [95% CI (-0.23)-(-0.01)]; p = 0.03] predicted smaller gains in CD4% after 3 years of HAART. A history of IVDU was associated with smaller absolute CD4 count increases at 1 year of therapy [OR -0.20 [95% CI (-128.32)-(-16.24)]; p = 0.01]. Use of nucleoside reverse transcriptase inhibitor (NRTI)-only regimens and of zidovudine as part of the NRTI backbone was associated with smaller and greater gains in CD4%, respectively. HCV replication per se does not impair the CD4 restoration in HIV-infected patients successfully treated with antiretroviral therapy. Lower baseline CD4 counts are the strongest predictors of greater CD4 gains over a 3-year period, while a history of IVDU negatively affects CD4 restoration only early after the initiation of HAART.