Chronic inflammation in a long-term cohort of HIV-infected patients according to the normalization of the CD4:CD8 ratio

Pillars of long-term antiretroviral therapy success

BACKGROUND

Meeting the challenge of antiretroviral therapy (ART) whose efficacy can last a lifetime requires continuous updating of the virological, pharmacological, and quality of life outcomes to be pursued and a continuous review of literature data on the efficacy and tolerability of new drugs and therapeutic strategies.

METHODS

With the aim of identifying open questions and answers about the current controversies in modern ART, we adapted the Design Thinking methodology to the needs of the design phase of a scientific article, involving a team of experts in HIV care.

RESULTS

Five main pillars of treatment success were discussed: sustained virologic suppression over time; immunological recovery; pharmacological attributes; long-term tolerability and safety of ART; and people's satisfaction and quality of life. The definition of the outcomes to be achieved in each thematic area and the tools to achieve them were reviewed and discussed.

CONCLUSIONS

Long-term treatment success should be intended as a combination of HIV-RNA suppression, immune recovery, and high quality of life. To achieve this, the regimen should be well-tolerated, with high potency, genetic barrier, and forgiveness, and should be tailored by a person-centered perspective, based on individual needs, preferences, and therapeutic history.

CD4/CD8 Ratio Outcome According to the Class of the Third Active Drug in Antiretroviral Therapy Regimens: Results From the Quebec Human Immunodeficiency Virus Cohort Study

BACKGROUND

The impact of different therapeutic classes of drugs in antiretroviral therapy (ART) regimens on the CD4/CD8 ratio is not well documented in people treated for HIV. The objective of this study was to analyze the long-term effect of exposure to integrase strand transfer inhibitor (INSTI) on CD4/CD8 ratio compared with nonnucleoside reverse transcriptase inhibitor (NNRTI) or protease inhibitor (PI) among ART-treated persons with HIV (PWH).

METHODS

Data from the Quebec HIV Cohort collected from 31 August 2017 were used. Our analysis included all patients in the cohort who received a first or subsequent ART regimen composed of 2 nucleoside reverse transcriptase inhibitors (NRTIs) and a third active drug of a different class (NNRTI, PI, or INSTI) for at least 16 weeks. Marginal structural Cox models were constructed to estimate the effect of different therapeutic classes on the CD4/CD8 ratio outcome.

RESULTS

Among the 3907 eligible patients, 972 (24.9%), 1996 (51.1%), and 939 (24.0%) were exposed to an ART regimen whose third active agent was an NNRTI, PI, or INSTI, respectively. The total follow-up time was 13 640.24 person-years. The weighted hazard ratio for the association between the third active class and CD4/CD8 ratio ≥1 was .56 (95% confidence interval [CI]: .48-.65) for patients exposed to NNRTI + 2 NRTIs and .41 (95% CI: .35-.47) for those exposed to PI + 2 NRTIs, compared with those exposed INSTI + 2 NRTIs.

CONCLUSIONS

For people treated for HIV, INSTI-based ART appears to be associated with a higher CD4/CD8 ratio than NNRTI and PI-based ART.

Identifying Longitudinal CD4:CD8 Ratio Trajectories Indicative of Chronic Renal Disease Risk among People Living with HIV: An Application of Growth Mixture Models

The incidence of chronic kidney disease (CKD) is increasing among people living with HIV (PLWH). Routine monitoring of indicators such as CD4:CD8 ratio might improve the early detection of CKD. Our objective was to identify clinically relevant CD4:CD8 ratio trajectories indicative of CKD risk. Participants were ≥ 18 years old, initiated antiretroviral therapy between 2000 and 2016, and were followed for ≥6 months until 31 March 2017 or last contact date. Outcome was incidence of CKD. Growth mixture models (GMMs) and decay models were used to compare CD4:CD8 ratio trajectories. Following GMM, 4547 (93.5%) participants were classified in Class 1 with 5.4% developing CKD, and 316 (6.5%) participants were classified in Class 2 with 20.9% developing CKD. The final model suggested that participants in Class 2 had 8.72 times the incidence rate of developing CKD than those in Class 1. Exponential decay models indicated a significant CD4:CD8 ratio decline among Class 2 participants who developed CKD. Among those who developed CKD in Class 2, starting at 5.5 years of follow-up, the slope of their ratio trajectory curve changed significantly, and the rate of decline increased dramatically. Routine monitored CD4:CD8 ratios can be an effective strategy to identify early CKD risk among PLWH.

Inflammation markers and the risk of hypertension in people living with HIV

Background

The incidence of hypertension is high in people living with HIV (PLWH). High-sensitivity C-reactive protein (hsCRP), systemic inflammation response index (SIRI), and neutrophil-to-monocyte ratio (NMR) are considered economic and convenient parameters that reflect the levels of inflammation in patients. Our aim was to explore whether indirect inflammation markers are associated with hypertension in PLWH.

Methods

This was a case-control study. The case group (hypertension) comprised PLWH with hypertension, and the control group (non-hypertension) comprised sex- and age-(± 3 years)-matched PLWH without hypertension. Demographic parameters, hsCRP, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), systemic immune- inflammation index (SII), SIRI, lymphocyte-to-monocyte ratio (LMR), platelet-to-neutrophil ratio (PNR), platelet-to-monocyte ratio (PMR), NMR, time to HIV diagnosis, antiretroviral therapy (ART) duration, recent CD4⁺ and CD8⁺ cell counts, recent CD4⁺/CD8⁺ ratio, recent HIV viral load (HIV-RNA),and recent ART regimen were obtained from the patients' electronic medical records. A t-test or Wilcoxon rank-sum test was performed to compare differences between the two groups, and conditional logistic regression was used to analyze the risk factors of hypertension. Correlations between inflammation markers and CD4⁺ cell counts, CD8⁺ cell counts, and CD4⁺/CD8⁺ ratio were analyzed using Spearman's correlation.

Results

In the hypertension group, body mass index (BMI), hsCRP, NLR, SII, SIRI, NMR, time to HIV diagnosis, ART duration, CD4⁺ and CD8⁺ cell counts, and CD4⁺/CD8⁺ ratio, the ratio of HIV-RNA < 100 copies/mL were all higher than those in the non-hypertension group, while the PNR was lower than that in the non-hypertension group. ART duration, CD4⁺ cell counts, HIV-RNA < 100 copies/mL, hsCRP, SIRI, and NMR were positively associated with hypertensive risk in PLWH. CD8⁺ cell counts and CD4⁺/CD8⁺ ratio was negatively associated with hypertensive risk in PLWH. SIRI was negatively correlated with CD4⁺ cell counts and CD8⁺ cell counts, but positively correlated with CD4⁺/CD8⁺ ratio.

Conclusions

We identified positive associations between inflammation markers hsCRP, SIRI, NMR and hypertensive risk in PLWH. Alleviating inflammation may help control or delay the occurrence of hypertension in PLWH.

Trajectories of CD4+/CD8+ T-Cells Ratio 96 Weeks after Switching to Dolutegravir-Based Two-Drug Regimens: Results from a Multicenter Prospective Cohort Study

The aim of the present study was to evaluate CD4/CD8 dynamics in patients on dolutegravir (DTG)-based two-drug regimens (2DRs) and compare them with DTG-containing triple-drug regimens (3DRs). A prospective observational study was performed in the context of the SCOLTA cohort. Experienced PWH with HIV-RNA < 50 copies/mL were included if they were on the DTG-2DR, the DTG + tenofovir/emtricitabine (TDF/FTC) regimen, the DTG + tenofovir alafenamide (TAF)/FTC regimen, or the DTG + abacavir/lamivudine (ABC/3TC) regimen; they were followed-up for at least one year. A total of 533 PWH were enrolled, 120 in the DTG + 3TC group, 38 in the DTG + protease inhibitors (PI) group, 67 in the DTG + rilpivirine (RPV) group, 49 in the DTG + TDF/FTC group, 27 in the DTG + TAF/FTC group, and 232 in the DTG + ABC/3TC group. After one year, the CD4/CD8 ratio significantly increased in the PWH treated with DTG + 3TC (+0.08 ± 0.26), DTG + TDF/FTC (+0.1 ± 0.19), and DTG + ABC/3TC (+0.08 ± 0.25). At two years, the CD4/CD8 increase was confirmed for PWH on DTG + TDF/FTC (+0.16 ± 0.28) and DTG + ABC/3TC (+0.1 ± 0.3). In the SCOLTA cohort, PWH on 2DRs experienced a CD4/CD8 increase only in the DTG + 3TC group. Controlled studies with longer follow-up will clarify the long-term immunological and clinical impacts of DTG-2DR.

Integrase inhibitor-based regimens are related to favorable systemic inflammatory index and platecrit scores in people living with HIV (PLWH) up to 2 years

OBJECTIVES

Despite the advances in antiretroviral treatment (ART), persistent inflammation remained a challenge. We analyzed the inflammatory-score changes through 2-years in people living with HIV (PLWH) treated with different antiretroviral regimes.

METHODS

This study was conducted in Hacettepe University HIV/AIDS Treatment and Research Center. PLWH diagnosed between 2014 and 2020 were included. Inflammatory and metabolic markers (CD4/CD8 ratio, C-reactive protein (CRP), Systemic Inflammatory Index (SII), Neutrophil-Lymphocyte Ratio (NLR), Mean Platelet Volume (MPV), Platecrite (PCT), and Low-Density Lipoprotein/High-Density Lipoprotein (LDL/HDL), Platelet-to-Lymphocyte Ratio (PLR) and ARTs were captured from database through 2-years from the diagnosis. The 2-year change (Δ) in markers was calculated and compared by ART type (backbone and 3rd agent). Mann-Whitney-U test and T-test were used for statistical analysis.

RESULTS

This study included 205 PLWH; 175 (85.4%) were male, and the mean age was 38.98 (±10.88) years. The number of PLWH with suppressed viremia (<40 HIV-RNA copies/ml) was 164 (80%) at the end of the second year. MPV increased significantly higher among PLWH receiving ABC/3TC compared to PLWH receiving TDF/FTC (p < 0.05). The CD4:CD8 ratio increased, and SII, NLR, LDL/HDL ratios decreased significantly among PLWH treated with integrase strand transfer inhibitors (INSTI) compared with protease inhibitors (PI) and Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs) (p < 0.05).

CONCLUSIONS

Integrase inhibitor treatment is related to favorable inflammatory marker profile among PLWH in the 2-year follow-up. A favorable inflammatory profile may, in turn, contribute to the prevention of non-communicable diseases (NCD) among PLWH. This study showed that simple, easy-to-calculate markers could be implemented to define ongoing inflammation among PLWH under suppressive ART.

Exceptional T CD4+ Recovery Post-antiretroviral Is Linked to a Lower HIV Reservoir with a Specific Immune Differentiation Pattern

We present a cohort of individuals who reached CD4⁺ T cell counts of greater than 1,000 cells/mm³ (Hypers) after starting antiretroviral treatment (ART) and compared them with those who reached between 350 and 999 CD4⁺ T cells/mm³ (Concordants). Demographic data, immune recovery kinetics, T CD4⁺ subset phenotypes, and integrated HIV DNA were analyzed. Data from individuals living with HIV on their first ART regimen and after 48 months of follow-up were obtained. Immune phenotype by Flow Cytometry analysis on whole blood was performed, cytokines were measured, and integrated HIV-1 DNA was measured by polymerase chain reaction. From a total of 424 individuals, 26 Hypers (6.1%), 314 Concordants (74.1%), and 84 (19.8%) discordants were identified. Hypers had a higher proportion of CD4⁺-naive (Nv) T cells (37.6 vs. 24.8, p < .05), and a low proportion of CD4⁺ effector memory T cells (27.9 vs. 39.4, p < .05), with similar results found in CD8⁺ T cells. Hypers demonstrated a higher percentage of CD4⁺CD45RA⁺CD31^neg cells with a lower response to interleukin-2 stimulation and a lower integrated HIV-1 DNA/CD4 ratio (1.2 vs. 2.89, p < .05). In Hypers, T cell recovery occurs very early after initiation of ART. Following this initial recovery state, their CD4⁺ T cell level homeostasis seems to be driven by nonthymic-central-Nv cells. This exceptional recovery is associated with a lower HIV reservoir, which may be related to an increase in noninfected CD4⁺ T cells. These patients could then be eligible candidates for cure trials.

A Real-World Evidence-Based Management of HIV by Differential Duration HAART Treatment and its Association with Incidence of Oral Lesions

Background

The efficacy of highly active antiretroviral therapy (HAART) can be estimated by the immunological response and the incidence of opportunistic infections.

Objective

This study aimed at evaluating the effectiveness of different durations of HAART in terms of immunological response markers (CD4 count and CD4/CD8 ratio) along with disease progression markers (incidence of oral lesions) in Chinese patients with HIV.

Methods

This single-center, retrospective, and real-world study included patients with HIV, grouped into a treatment group and treatment-naïve group, of which the former was further divided into 6, 12, and 18 months based on the treatment duration. The CD4 and CD8 cell counts were analyzed by the FACSCalibur flow cytometry. Kruskal-Wallis test was applied to determine the outcome of different duration of HAART. Oral examination was carried out according to the WHO type IV examination.

Results

In 246 patients with HIV, CD4 counts increased significantly post-HAART compared to pre-HAART in all three treatment groups (P<.001), while CD8 count decreased significantly (P<.05) in all three treated groups. A significant association of HAART with the CD4/CD8 ratio was observed (P<.001). A significant increase in CD4 count was observed between 12-months and 18-months treatment groups (P<.05). The occurrence of oral lesions reduced significantly in the treatment group.

Conclusion

We observed a better response to the HAART regimen with 18-months of duration than 12-months and 6-months therapies and reduction in oral lesions.

Endothelial Activation, Innate Immune Activation, and Inflammation Are Associated With Postbronchodilator Airflow Limitation and Obstruction Among Adolescents Living With HIV

BACKGROUND

Chronic inflammation, innate immune activation, T-cell imbalance and endothelial activation have been linked with lung diseases. We sought to determine whether markers of these pathophysiologic pathways were associated with spirometry and chest computed tomography (CT) abnormalities among adolescents living with HIV (ALWH).

SETTING

Coptic Hope Center for Infectious Diseases in Nairobi, Kenya.

METHODS

We performed a cross-sectional study of ALWH (10-19 years old). Participants underwent chest CT, spirometry, and venipuncture for serum biomarkers. We also collected demographic, anthropometric, T-cell subset, antiretroviral therapy, and exposure data. We compared characteristics and biomarkers by airflow obstruction [postbronchodilator FEV1/FVC z-score (zFEV1/FVC) < -1.64]. We used multivariable linear regression to determine associations of log10-transformed biomarkers and chest CT abnormalities with lower postbronchodilator zFEV1/FVC (airflow limitation). We performed exploratory principal components analysis on biomarkers, and determined associations of factors with postbronchodilator zFEV1/FVC and chest CT abnormalities.

RESULTS

Of 47 participants with acceptable quality spirometry, 21 (45%) were female, median age was 13 years and 96% had perinatally-acquired HIV. Median CD4 was 672 cells/µL. Overall, 28% had airflow obstruction and 78% had a chest CT abnormality; airflow obstruction was associated with mosaic attenuation (P = 0.001). Higher endothelial activation (sVCAM-1, sICAM-1), inflammation and innate immune activation (serum amyloid-A, sTREM-1, sCD163), and T-cell imbalance (lower CD4/CD8) markers were associated with airflow limitation. Factors comprising endothelial and innate immune activation were associated with airflow limitation.

CONCLUSIONS

Endothelial activation, innate immune activation, T-cell imbalance, and chronic inflammation are associated with airflow limitation and obstruction, providing insights into chronic lung disease pathophysiology among ALWH.

Acute HIV Infection and CD4/CD8 Ratio Normalization After Antiretroviral Therapy Initiation

BACKGROUND

We estimated the effect of initiating virologically suppressive antiretroviral therapy (ART) during acute HIV infection versus chronic HIV infection (AHI vs. CHI) on CD4/CD8 ratio normalization.

SETTING

A prospective clinical cohort study.

METHODS

We included patients initiating ART with AHI and CHI between 2000 and 2015 and compared time from ART initiation to the first normal CD4/CD8 ratio (defined as CD4/CD8 ≥1) using Kaplan-Meier curves and multivariable Cox proportional hazards models. Patient time was censored at virologic failure, lost to follow-up, or death. We also characterized CD4, CD8, and CD4/CD8 trajectories over the first 3 years of ART.

RESULTS

The 1198 patients were 27% female and 60% African American, with a median age of 37 years (interquartile range 28-47) at ART initiation. The 83 AHI patients were more likely male, younger, and of white race, than CHI patients. After 2 years of suppressive ART, 70% of AHI patients achieved a normal CD4/CD8 ratio, compared to 6%-38% of CHI patients, with greater likelihood of normalization at higher baseline CD4 counts. Time to normalization was shortest among AHI patients, followed by CHI patients with higher baseline CD4. The adjusted hazard ratio for time to normalization for AHI patients compared to CHI patients with baseline CD4 >350 was 4.33 (95% CI: 3.16 to 5.93). Higher baseline CD4/CD8 ratio was also associated with time to normalization (adjusted hazard ratio 1.54; 1.46, 1.63, per 0.1 increase in ratio).

CONCLUSIONS

Initiating ART during AHI at higher baseline CD4 cell counts and CD4/CD8 ratios was associated with shorter time to CD4/CD8 ratio normalization.

CD4:CD8 ratio comparison between cohorts of HIV-positive Asians and Caucasians upon commencement of antiretroviral therapy

BACKGROUND

In the era of effective antiretroviral treatment (ART) CD4:CD8 ratio is proposed as a potential marker for HIV-positive (HIV+) patients at increased risk for non-AIDS comorbidities. The current study aims to compare CD4:CD8 ratio between Asian and Caucasian HIV+ patients.

METHODS

HIV+ patients from the Australian HIV Observational Database (AHOD) and the TREAT Asia HIV Observational Database (TAHOD) meeting specific criteria were included. In these analyses Asian and Caucasian status were defined by cohort. Factors associated with a low CD4:CD8 ratio (cutoff <0.2) prior to ART commencement, and with achieving a normal CD4:CD8 ratio (>1) at 12 and 24 months post ART commencement were assessed using logistic regression.

RESULTS

There were 591 patients from AHOD and 2,620 patients from TAHOD who met the inclusion criteria. TAHOD patients had a significantly (P<0.001) lower odds of having a baseline (prior to ART initiation) CD4:CD8 ratio greater than 0.2. After 12 months of ART, AHOD patients were more than twice as likely to achieve a normal CD4:CD8 ratio compared to TAHOD patients (15% versus 6%). However, after adjustment for confounding factors there was no significant difference between cohorts in the odds of achieving a CD4:CD8 ratio >1 (P=0.475).

CONCLUSIONS

We found a significantly lower CD4:CD8 ratio prior to commencing ART in TAHOD compared to AHOD even after adjusting for confounders. However, after adjustment, there was no significant difference between the cohorts in odds of achieving normal ratio. Baseline CD4⁺ and CD8⁺ counts seem to be the main driver for this difference between these two populations.

Serum albumin and mortality in patients with HIV and end-stage renal failure on peritoneal dialysis

Background

Peritoneal dialysis (PD) is an easily implementable dialysis modality in end-stage renal disease (ESRD). PD may improve access to renal replacement therapy in low- and middle-income countries; however, these countries have a higher prevalence of protein-energy wasting in patients and poorer socioeconomic conditions. We evaluated the effects of HIV infection on serum albumin levels in ESRD patients starting continuous ambulatory PD (CAPD) and mortality outcomes.

Methods

We conducted a single-center prospective cohort study of consecutive incident CAPD patients recruited from two hospitals in Durban, South Africa, from September 2012 to February 2015. Seventy HIV-negative and 70 HIV-positive ESRD patients were followed monthly for serum albumin levels and mortality events during the first 18 months of CAPD therapy.

Results

The HIV-positive cohort recorded 28 deaths (40%) among patients with a functional CAPD catheter at 18 months and 13 deaths (18.6%) in the HIV-negative cohort (p = 0.005). The mean serum albumin levels were lower in the HIV-positive cohort than in the HIV-negative cohort during the 18-month follow-up. The mean difference in serum albumin levels between the two cohorts was 4.24 g/L (95% confidence interval [CI] 2.02–6.46, p<0.001) at baseline and 3.99 g/L (95% CI 1.19–6.79, p = 0.006) at 18 months. HIV-positive status (adjusted regression coefficient -2.84, CI -5.00–-0.67, p = 0.011), diabetes (adjusted coefficient -2.85; CI, -5.58–-0.12; p = 0.041), and serum C-reactive protein and blood hemoglobin levels were independent predictors of serum albumin levels on multivariable linear regression. Baseline serum albumin <25 g/L (subdistribution-hazard ratio [SHR] 13.06, 95% CI 3.09–55.14, p<0.001) and CD4⁺ cell count <200 cells/μL (SHR 3.2, CI 1.38–7.45, p = 0.007) were independent predictors of mortality in our competing risk model.

Conclusions

HIV infection can adversely affect serum albumin levels in ESRD patients managed with CAPD, while low baseline serum albumin levels and impaired immunity reliably predict mortality.

CD4:CD8 ratio in children with perinatally acquired HIV-1 infection

Objectives

In adults with horizontally acquired HIV infection, an inverted CD4:CD8 ratio is associated with persistent immune activation, size of HIV reservoir and predicts an increased risk of non‐AIDS‐defining adverse events. Normalization of this ratio with antiretroviral therapy (ART) is suboptimal in adults, despite viral suppression, and is less well described in paediatric populations. We investigated rates of CD4:CD8 ratio recovery in children with perinatally acquired HIV infection (PaHIV) on ART.

Methods

A cross‐sectional, retrospective analysis of routine clinical data in children with PaHIV (5–18 years old) attending a single UK centre was carried out.

Results

CD4:CD8 normalization was seen in 62% of children on suppressive ART. A negative correlation was found between current CD4:CD8 ratio and age at start of ART. Positive correlations were found between current CD4:CD8 ratio and total time with suppressed HIV viral load and nadir CD4 counts. Multiple linear regression analysis showed that age at start of ART was significantly associated with current CD4:CD8 ratio (standardized β = −0.680; P < 0.001). Patient sex, ethnicity and antiretroviral regimen did not affect ratio recovery.

Conclusions

We found higher rates of CD4:CD8 ratio normalization compared with previous adult studies. Children who started ART at a younger age were more likely to recover a normal ratio. The current policy of universal treatment for all HIV‐positive adults and children will enhance immunological normalization.

Long terms trends in CD4+ cell counts, CD8+ cell counts, and the CD4+ : CD8+ ratio

Supplemental Digital Content is available in the text

Objective:

Model trajectories of CD4⁺ and CD8⁺ cell counts after starting combination antiretroviral therapy (ART) and use the model to predict trends in these counts and the CD4⁺ : CD8⁺ ratio.

Design:

Cohort study of antiretroviral-naïve HIV-positive adults who started ART after 1997 (ART Cohort Collaboration) with more than 6 months of follow-up data.

Methods:

We jointly estimated CD4⁺ and CD8⁺ cell count trends and their correlation using a bivariate random effects model, with linear splines describing their population trends, and predicted the CD4⁺ : CD8⁺ ratio trend from this model. We assessed whether CD4⁺ and CD8⁺ cell count trends and the CD4⁺ : CD8⁺ ratio trend varied according to CD4⁺ cell count at start of ART (baseline), and, whether these trends differed in patients with and without virological failure more than 6 months after starting ART.

Results:

A total of 39 979 patients were included (median follow-up was 53 months). Among patients with baseline CD4⁺ cell count at least 50 cells/μl, predicted mean CD8⁺ cell counts continued to decrease between 3 and 15 years post-ART, partly driving increases in the predicted mean CD4⁺ : CD8⁺ ratio. During 15 years of follow-up, normalization of the predicted mean CD4⁺ : CD8⁺ ratio (to >1) was only observed among patients with baseline CD4⁺ cell count at least 200 cells/μl. A higher baseline CD4⁺ cell count predicted a shorter time to normalization.

Conclusion:

Declines in CD8⁺ cell count and increases in CD4⁺ : CD8⁺ ratio occurred up to 15 years after starting ART. The likelihood of normalization of the CD4⁺ : CD8⁺ ratio is strongly related to baseline CD4⁺ cell count.

Switching to dual/monotherapy determines an increase in CD8+ in HIV-infected individuals: an observational cohort study

BACKGROUND

The CD4/CD8 ratio has been associated with the risk of AIDS and non-AIDS events. We describe trends in immunological parameters in people who underwent a switch to monotherapy or dual therapy, compared to a control group remaining on triple antiretroviral therapy (ART).

METHODS

We included patients in Icona who started a three-drug combination ART regimen from an ART-naïve status and achieved a viral load ≤ 50 copies/mL; they were subsequently switched to another triple or to a mono or double regimen. Standard linear regression at fixed points in time (12-24 months after the switch) and linear mixed model analysis with random intercepts and slopes were used to compare CD4 and CD8 counts and their ratio over time according to regimen types (triple vs. dual and vs. mono).

RESULTS

A total of 1241 patients were included; 1073 switched to triple regimens, 104 to dual (72 with 1 nucleoside reverse transcriptase inhibitor (NRTI), 32 NRTI-sparing), and 64 to monotherapy. At 12 months after the switch, for the multivariable linear regression the mean change in the log₁₀ CD4/CD8 ratio for patients on dual therapy was -0.03 (95% confidence interval (CI) -0.05, -0.0002), and the mean change in CD8 count was +99 (95% CI +12.1, +186.3), taking those on triple therapy as reference. In contrast, there was no evidence for a difference in CD4 count change. When using all counts, there was evidence for a significant difference in the slope of the ratio and CD8 count between people who were switched to triple (points/year change ratio = +0.056, CD8 = -25.7) and those to dual regimen (ratio = -0.029, CD8 = +110.4).

CONCLUSIONS

We found an increase in CD8 lymphocytes in people who were switched to dual regimens compared to those who were switched to triple. Patients on monotherapy did not show significant differences. The long-term implications of this difference should be ascertained.

Impact of dolutegravir and efavirenz on immune recovery markers: results from a randomized clinical trial

OBJECTIVES

CD4/CD8 ratio and CD4⁺ T-cell percentage (CD4%) predicts the risk of AIDS and non-AIDS events. Multiple T-cell marker recovery (MTMR) has been proposed as the most complete level of immune reconstitution. We quantified differences in the CD4/CD8 ratio, CD4% recovery and MTMR after starting HIV-1 treatment with dolutegravir/abacavir/lamivudine vs. efavirenz (EFV)/tenofovir (TDF)/emtricitabine (FTC).

METHODS

Exploratory post hoc analysis of the SINGLE study, a randomized double-blind, clinical trial. Percentage differences and corresponding precision based on 95% confidence intervals, and p values were calculated for CD4/CD8 ratio normalization, CD4% normalization and the achievement of MTMR. Cox models taking into account competing risks were used to estimate sub-hazard ratios when comparing the times to normalization of the CD4/CD8 ratio and the CD4% by treatment arm.

RESULTS

Data from 833 participants were analysed (414 in the dolutegravir/abacavir/lamivudine arm). There were no statistically significant differences in the proportion of patients who reached a CD4/CD8 ratio ≥0.5 at weeks 48 and 96. However, at week 96, the proportion of patients with a CD4/CD8 ratio ≥1 was higher in the EFV-TDF-FTC group (difference, 11.70; 95% confidence interval, 4.49-18.91; p 0.002). The decrease from baseline in CD8⁺ cell count was consistently greater in the EFV-TDF-FTC arm. Analysis of CD4⁺ percentages showed no significant differences during the study. The proportion of patients attaining a MTMR was higher in the EFV-TDF-FTC group, although the difference was only statistically significant at week 96 (p 0.001).

CONCLUSIONS

EFV-TDF-FTC showed significantly greater increases in CD4/CD8 ratio ≥1.0 or MTMR beyond treatment week 96. Additional studies are necessary to better understand the impact of these findings.

Combining CD4 recovery and CD4: CD8 ratio restoration as an indicator for evaluating the outcome of continued antiretroviral therapy: an observational cohort study

OBJECTIVES

Immune recovery following highly active antiretroviral therapy (HAART) is commonly assessed by the degree of CD4 reconstitution alone. In this study, we aimed to assess immune recovery by incorporating both CD4 count and CD4:CD8 ratio.

DESIGN

Observational cohort study SETTING AND PARTICIPANTS: Clinical data from Chinese HIV-positive patients attending the largest HIV service in Hong Kong and who had been on HAART for ≥4 years were accessed.

MAIN OUTCOME MEASURES

Optimal immune outcome was defined as a combination of a CD4 count ≥500/μL and a CD4:CD8 ratio ≥0.8.

RESULTS

A total of 718 patients were included for analysis (6353 person-years). At the end of year 4, 318 out of 715 patients achieved CD4 ≥500/μL, of which only 33% (105 out of 318) concurrently achieved CD4:CD8 ratio ≥0.8. Patients with a pre-HAART CD8 ≤800/μL (428 out of 704) were more likely to be optimal immune outcome achievers with CD4 ≥500/μL and CD4:CD8 ratio ≥0.8, the association of which was stronger after adjusting for pre-HAART CD4 counts. In a multivariable logistic model, optimal immune outcome was positively associated with male gender, younger pre-HAART age and higher pre-HAART CD4 count, longer duration of HAART and pre-HAART CD8 ≤800/μL. Treatment regimen and cumulative viral loads played no significant role in the pattern of immune recovery.

CONCLUSIONS

A combination of CD4 count and CD4:CD8 ratio could be a useful approach for the characterisation of treatment outcome over time, on top of monitoring CD4 count alone.

Immune recovery of middle-aged HIV patients following antiretroviral therapy: An observational cohort study

In HIV-infected persons, age is negatively associated with optimal CD4 recovery following antiretroviral therapy. Our understanding of the situation in older adults, especially the middle-aged is, however, limited. We undertook to examine the latter's pattern of CD4/CD8 recovery following antiretroviral therapy.Retrospective clinical cohort data of HIV patients diagnosed between 1985 and 2014 in Hong Kong were collected. They were categorized by age at treatment initiation, viz., young adults (age 18-49), middle-aged (age 50-64), and elderly (≥65 years' old). Predictors of immune recovery (CD4 count, CD8 count, CD4/CD8 ratio) over time were examined using multivariable linear generalized estimating equations.A total of 2754 patients (aged ≥18) have been on antiretroviral therapy, with baseline characteristics similar between middle-aged and the elderly. Late diagnosis, defined as progression to AIDS within 3 months of HIV diagnosis, was less common in middle-aged (odds ratio = 0.58, 95% confidence interval = 0.37-0.91). Among Chinese patients who have been on treatment for ≥4 years (n = 913), 80.6%, 14.6%, and 4.8% were young adults, middle-aged, and elderly respectively. Late treatment initiation, defined as AIDS diagnosis or CD4 count ≤100 cells/μL before treatment, was common in middle-aged and elderly, the former however had faster CD4 recovery (3.95 vs. 3.36 cells/μL/month), but slower CD8 decline (-1.76 vs. -4.34 cells/μL/month) and CD4/CD8 normalization (0.009 vs. 0.0101/month).As a transitional age group, the immune recovery of middle-aged patients lagged behind young adults largely because of late treatment initiation. Following adoption of early and non-CD4-guided treatment initiation, their long-term clinical outcome is expected to improve.

CD4 and CD4/CD8 ratio progression in HIV-HCV infected patients after achievement of SVR

BACKGROUND

In HIV-HCV co-infected patients, the long-term effects of HCV eradication on HIV disease progression are still unclear.

OBJECTIVES

This study aims to determine if CD4 and CD4/CD8 ratio slopes improved after anti-HCV treatment in patients achieving a sustained virological response (SVR).

STUDY DESIGN

A total of 116 HIV-HCV co-infected patients, previously treated with Peg-IFN/RBV, were divided into two groups: SVR (55 patients who had achieved SVR), and non-SVR (61 patients). Retrospective data before and after anti-HCV therapy were obtained for all patients, with a median 8 year-follow-up. Multilevel mixed models were fitted to assess the trends over time of FIB-4 score, APRI score, CD4, CD8 cell count and CD4/CD8 ratio.

RESULTS

Median HIV-infection duration, HCV-RNA and GGT baseline levels were higher in non-SVR compared to the SVR group. A significantly decreased FIB-4 (p<0.001) and APRI trend (p<0.001) after SVR was observed in SVR patients compared to those non-SVR. After adjustment for HIV duration, there was no significant difference between the two groups for absolute CD4 (p=0.08) or percentage CD4 slope (p=0.6) over time. The CD4/CD8 ratio trend also demonstrated a similar progressive increase in both groups (p=0.2). During follow-up, six deaths were reported in the non-SVR group versus no death for the SVR group, while no difference in AIDS and non-AIDS events was observed.

CONCLUSIONS

Achievement of SVR determines an important beneficial impact in terms of liver-related mortality and fibrosis regression, but does not seem to alter neither the slope of long term CD4 gain nor the CD4/CD8 ratio evolution in ART-treated HIV-HCV co-infected patients.

Association of immune recovery with hyperlipidaemia and apolipoprotein gene polymorphisms following highly active antiretroviral therapy in a cohort of Chinese HIV patients

OBJECTIVE

To examine the associations between CD4 recovery, dyslipidaemia and apolipoprotein (APO) gene single nucleotide polymorphisms (SNPs) following highly active antiretroviral therapy (HAART).

DESIGN

Retrospective observational cohort study.

SETTING

A major HIV care clinic in Hong Kong.

PARTICIPANTS

197 Chinese treatment-naïve HIV patients.

OUTCOME MEASURES

Maximum CD4 count and its rise 2-3 years after HAART initiation and their association with abnormal total cholesterol (TC), triglyceride (TG) and 8 selected APO SNP at multiple time points.

RESULTS

Before HAART, abnormal levels of TC, TG, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol were detected in 13%, 26%, 59% and 19% of the recruited patients, respectively. APOA5 -1131T>C and c.553G>T were significantly associated with high pre-HAART TG while APOE 2198C>T was correlated with high TG at baseline and/or a rise 2-3 years following HAART initiation. Poor CD4 achievement, defined as the highest CD4 count <350/μL and a net gain of <100/μL, was associated with a low CD4 count ≤200/μL at baseline and a rise of TC beyond 5.17 mmol/L following HAART with or without the use of antilipid agents. Conversely, satisfactory CD4 achievement was associated with APOC3 3238GG genotype. Applying a linear generalised estimating equation, APOA5 -1131T>C was shown to be a predictor of a weaker temporal trend for CD4 response in the presence of a low baseline CD4≤200/μL.

CONCLUSIONS

Dyslipidaemia plays a predictive role in impacting immunological recovery following HAART, which could be partly explained by the APO gene SNP.

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.

CD4:CD8 ratio as a frontier marker for clinical outcome, immune dysfunction and viral reservoir size in virologically suppressed HIV-positive patients

Introduction

Absolute CD4 T cell count and plasma viral load have been established as predictors of HIV disease progression, and CD4 T cell count is used as an indicator for initiation of antiretroviral therapy. Following long-term therapy, patients generally present with significant CD4 T cell recovery contrasting with persistently elevated CD8 T cell counts, which leads to a partial restoration of CD4:CD8 ratio. This review focuses on the relevance of the CD4:CD8 ratio on clinical outcomes, immune dysfunction and HIV reservoir size in long-term treated patients.

Method

We conducted a comprehensive literature review of publications in English language using major electronic databases. Our search was focused on factors contributing to CD4:CD8 T cell ratio and clinical outcome in adult HIV-positive patients in the context of treated infection.

Discussion

Low CD4:CD8 ratio has been linked to ageing and acts as a predictor of mortality in the general population. This ratio may represent the combined effects of inflammation and immunological changes called “inflammaging.” Although the mechanisms underlying partial correction of the CD4:CD8 ratio and persistently elevated CD8 T cell count in long-term treated patients remain poorly understood, it has been recently indicated that patients with optimal CD4 T cell recovery and low CD4:CD8 ratio still harbour increased immune activation, an immune senescent phenotype and have a higher risk of non-AIDS morbidity and mortality. This review reconsiders CD4:CD8 ratio in the light of advances in the understanding of immune dysfunction and examines its pathophysiological features and implications on clinical outcome and HIV reservoir size in long-term treated HIV-positive adults.

Conclusion

The CD4:CD8 ratio can contribute to the immunological evaluation of treated patients in a long-term follow-up and may be applied for monitoring both immune dysfunction and viral reservoir size in immune-based clinical trials.