Risk of SARS-CoV-2 infection in patients with hematologic diseases receiving tixagevimab/cilgavimab as pre-exposure prophylaxis in most recent Omicron sublineages era

INTRODUCTION

Whether pre-exposure prophylaxis (PrEP) with tixagevimab/cilgavimab 150mg/150 mg (T/C) in individuals with hematological diseases (HD) may lead to a reduced risk of Breakthrough SARS CoV2 infection/hospitalization or death in the Omicron era remains to be established.

METHODS

Observational study including participants with HD who received PrEP. breakthrough infections were defined as a SARS-CoV-2 positivity by RT-PCR. The incidence of breakthrough infections (95%CI) and of breakthrough infections /hospitalization/death was calculated using the Kaplan-Meier method and as the number of breakthrough infections per 100-PYFU according to the circulating variant (VoC). A Poisson regression model was used to evaluate the association between the rate of incidence and circulating VoCs after controlling for demographics and clinical factors.

RESULTS

We included 550 HD patients: 71% initiated T/C PrEP when BA.5 was the most prevalent, followed by XBB/EG, BA.2 and BA.1 (19%, 7% and 3%, respectively). Overall, the 1-year incidence estimate of breakthrough infections/hospitalization/death was 24% (18.7-29.4%). A greater risk of incident infections was observed when BA.5 and XBB/EG sub-lineages circulated [aRR 5.05 (2.17, 11.77); p<.001 and 3.82 (1.50, 9.72); p=0.005, compared to BA.1, respectively].

CONCLUSIONS

The one-year incidence of SARS-CoV-2 breakthrough infections/hospitalization/death was 24% which is in line with what observed in other similar studies. The risk appeared to be higher when more recent Omicron sub-lineages were circulating suggesting a reduction of in vitro neutralization.

Poor durability of the neutralizing response against XBB sublineages after a bivalent mRNA COVID-19 booster dose in persons with HIV

We estimated the dynamics of the neutralizing response against XBB sublineages and T cell response in persons with HIV (PWH) with previous AIDS and/or CD4 < 200/mm3 receiving the bivalent original strain/BA.4-5 booster dose in fall 2022. Samples were collected before the shot (Day 0), 15 days, 3, and 6 months after. PWH were stratified by immunization status: hybrid immunity (HI; vaccination plus COVID-19) versus nonhybrid immunity (nHI; vaccination only). Fifteen days after the booster, 16% and 30% of PWH were nonresponders in terms of anti-XBB.1.16 or anti-EG.5.1 nAbs, respectively. Three months after, a significant waning of anti-XBB.1.16, EG.5.1 and -XBB.1 nAbs was observed both in HI and nHI but nAbs in HI were higher than in nHI. Six months after both HI and nHI individuals displayed low mean levels of anti-XBB.1.16 and EG.5.1 nAbs. Regarding T cell response, IFN-γ values were stable over time and similar in HI and nHI. Our data showed that in PWH, during the prevalent circulation of the XBB.1.16, EG.5.1, and other XBB sublineages, a mRNA bivalent vaccine might not confer broad protection against them. With a view to the 2023/2024 vaccination campaign, the use of the monovalent XBB.1.5 mRNA vaccine should be urgently warranted in PWH to provide adequate protection.

Immunogenicity and reactogenicity of modified vaccinia Ankara pre-exposure vaccination against mpox according to previous smallpox vaccine exposure and HIV infection: prospective cohort study

Background

Pre-exposure vaccination with MVA-BN has been widely used against mpox to contain the 2022 outbreak. Many countries have defined prioritized strategies, administering a single dose to those historically vaccinated for smallpox, to achieve quickly adequate coverage in front of low supplies. Using epidemiological models, real-life effectiveness was estimated at approximately 36%-86%, but no clinical trials were performed. Few data on MVA-BN immunogenicity are currently available, and there are no established correlates of protection. Immunological response in PLWH in the context of the 2022 outbreak was also poorly described.

Methods

Blood samples were collected from participants eligible for pre-exposure MVA-BN vaccination before (T1) receiving a full course of vaccine (single-dose for vaccine-experienced or smallpox-primed and two-dose for smallpox vaccine-naïve or smallpox non-primed) and one month after the last dose (T2 and T3, respectively). MPXV-specific IgGs were measured by in-house immunofluorescence assay, using 1:20 as screening dilution, MPXV-specific nAbs by 50% plaque reduction neutralization test (PRNT50, starting dilution 1:10), and IFN-γ-producing specific T cells to MVA-BN vaccine, by ELISpot assay. Paired or unpaired t-test and Wilcoxon or Mann-Whitney test were used to analyse IgG and nAbs, and T-cell response, as appropriate. The probability of IgG and nAb response in vaccine-experienced vs. vaccine-naïve was estimated in participants not reactive at T1. The McNemar test was used to evaluate vaccination's effect on humoral response both overall and by smallpox vaccination history. In participants who were not reactive at T1, the proportion of becoming responders one month after full-cycle completion by exposure groups was compared by logistic regression and then analysed by HIV status strata (interaction test). The response was also examined in continuous, and the Average Treatment Effect (ATE) of the difference from baseline to schedule completion according to previous smallpox vaccination was estimated after weighting for HIV using a linear regression model. Self-reports of adverse effects following immunization (AEFIs) were prospectively collected after the first MVA-BN dose (T1). Systemic (S-AEFIs: fatigue, myalgia, headache, GI effects, chills) and local (L-AEFIs: redness, swelling, pain) AEFIs were graded as absent (grade 0), mild (1), moderate (2), or severe (3). The maximum level of severity for S-AEFIs and L-AEFIs ever experienced over the 30 days post-dose by vaccination exposure groups were analysed using a univariable multinomial logistic regression model and after adjusting for HIV status; for each of the symptoms, we also compared the mean duration by exposure group using an unpaired t-test.

Findings

Among the 164 participants included, 90 (54.8%) were smallpox vaccine-experienced. Median age was 49 years (IQR 41-55). Among the 76 (46%) PLWH, 76% had a CD4 count >500 cells/μL. There was evidence that both the IgG and nAbs titers increased after administration of the MVA-BN vaccine. However, there was no evidence for a difference in the potential mean change in humoral response from baseline to the completion of a full cycle when comparing primed vs. non-primed participants. Similarly, there was no evidence for a difference in the seroconversion rate after full cycle vaccination in the subset of participants not reactive for nAbs at T1 (p = 1.00 by Fisher's exact test). In this same analysis and for the nAbs outcome, there was some evidence of negative effect modification by HIV (interaction p-value = 0.17) as primed people living with HIV (PLWH) showed a lower probability of seroconversion vs. non-primed, and the opposite was seen in PLWoH. When evaluating the response in continuous, we observed an increase in T-cell response after MVA-BN vaccination in both primed and non-primed. There was evidence for a larger increase when using the 2-dose vs. one-dose strategy with a mean difference of -2.01 log2 (p ≤ 0.0001), after controlling for HIV. No evidence for a difference in the risk of developing any AEFIs of any grade were observed by exposure group, except for the lower risk of grade 2 (moderate) fatigue, induration and local pain which was lower in primed vs. non-primed [OR 0.26 (0.08-0.92), p = 0.037; OR 0.30 (0.10-0.88), p = 0.029 and OR 0.19 (0.05-0.73), p = 0.015, respectively]. No evidence for a difference in symptom duration was also detected between the groups.

Interpretation

The evaluation of the humoral and cellular response one month after the completion of the vaccination cycle suggested that MVA-BN is immunogenic and that the administration of a two-dose schedule is preferable regardless of the previous smallpox vaccination history, especially in PLWH, to maximize nAbs response. MVA-BN was safe as well tolerated, with grade 2 reactogenicity higher after the first administration in vaccine-naïve than in vaccine-experienced individuals, but with no evidence for a difference in the duration of these adverse effects. Further studies are needed to evaluate the long-term duration of immunity and to establish specific correlates of protection.

Funding

The study was supported by the National Institute for Infectious Disease Lazzaro Spallanzani IRCCS "Advanced grant 5 × 1000, 2021" and by the Italian Ministry of Health "Ricerca Corrente Linea 2".

Predictive Factors for Pregnancy-Related Persistent Pelvic Girdle Pain (PPGP): A Systematic Review

Background and Objectives: To identify the most frequently reported predictive factors for the persistency of pregnancy-related pelvic girdle pain (PPGP) at 3-6 months after childbirth in women with PPGP alone or PPGP in association with pregnancy-related lower back pain (PLBP). Methods: Eligibility criteria: Two authors independently selected studies excluding PPGP determined by a specific, traumatic, gynecological/urological cause or isolated PLBP and studies that did not include the presence/absence of PPGP as the the primary outcome. We, instead, included studies with an initial assessment in pregnancy (within 1 month of delivery) and with a follow-up of at least 3 months after delivery. Data sources: The research was performed using the databases of Medline, Cochrane, Pedro, Scopus, Web of Science and Cinahl from December 2018 to January 2022, following the indications of the PRISMA statement 2021 and the MOOSE checklist. It includes observational cohort studies in which data were often collected through prospective questionnaires (all in English). Study appraisal and risk of bias: Two independent authors performed evaluations of the risk of bias (ROB) using the quality in prognostic studies (QUIPS) tool. Synthesis of results: An in-depth qualitative analysis was conducted because, due to a high degree of heterogeneity in the data collection of the included studies and a lack of raw data suitable for quantitative analysis, it was not possible to carry out the originally planned meta-analyses for the subgroups. Results: The research process led to the inclusion of 10 articles which were evaluated using the QUIPS tool: 5 studies were evaluated as low ROB and 5 were evaluated as moderate ROB. High levels of pain in pregnancy, a large number of positive provocation tests, a history of lower back pain and lumbo-pelvic pain, high levels of disability in pregnancy, neurotic behavior and high levels of fear-avoidance belief were identified as strong predictors of long-term PPGP, while there was weak or contradictory evidence regarding predictions of emotional distress, catastrophizing and sleep disturbances. Discussion: The impossibility of carrying out the meta-analysis by subgroups suggests the need for further research with greater methodological rigor in the acquisition of measures based on an already existing PPGP core predictors/outcome sets.

Neutralizing activity and T-cell response after bivalent fifth dose of messenger RNA vaccine in people living with HIV

OBJECTIVES

To investigate immunogenicity of SARS-CoV-2 vaccine third booster dose (3BD; fifth dose) with bivalent vaccine original/BA4/5 vaccine in people living with HIV (PLWH).

METHODS

This is an observational cohort study to evaluate the outcomes of SARS-CoV-2 vaccination (HIV-VAC study). We analyzed microneutralization assay and interferon-γ production in 48 PLWH on antiretroviral therapy with clusters of differentiation (CD4) count <200 cell/mm3 and/or previous AIDS according to immunization status: vaccinated PLWH who had a previous SARS-CoV-2 infection (hybrid immunization, HI) vs those only vaccinated (non-hybrid immunization, nHI) and current CD4 count.

RESULTS

After 15 days from its administration (T1), the 3BD bivalent messenger RNA vaccine elicited a statistically significant increase of neutralizing antibodies (nAbs) geometric mean titers from T0 to T1 against W-D614G (fold increase 4.8; P <0.0001), BA.5 (8.6 P <0.0001), BQ.1.1 (6.4, P <0.0001) and XBB.1 (6.5, P <0.0001). When compared to BA.5, nAbs geometric mean titers against BQ.1.1 and XBB.1 decreased by 3.5 and 4.1-fold, respectively. After controlling for age, years from AIDS diagnosis, CD4 count at administration and CD4 count nadir, the fold change reduction in nAbs response to other variants of concerns as compared to BA.1, was larger in participants with HI vs those nHI: 0.59 lower (95% confidence interval 0.36-0.97, P = 0.04) for BQ.1.1 and 0.67 lower (95% confidence interval: 0.47-0.96, P = 0.03) for XBB.1. In contrast, the analysis carried little evidence for an association between current CD4 count and response to the fifth dose of bivalent vaccine. Furthermore, cell-mediated immunity remained stable.

CONCLUSION

Our data support the current recommendation of offering bivalent mRNA vaccine booster doses to PLWH with low CD4 count or previous AIDS at first vaccination, especially in those who never previously acquired SARS-CoV-2 and regardless of current CD4 count.

Humoral and cellular immune response elicited by mRNA vaccination against SARS-CoV-2 in people living with HIV (PLWH) receiving antiretroviral therapy (ART) according with current CD4 T-lymphocyte count

Background

Data on SARS-CoV-2 vaccine immunogenicity in PLWH are currently limited. Aim of the study was to investigate immunogenicity according to current CD4 T-cell count

Methods

PLWH on ART attending a SARS-CoV-2 vaccination program, were included in a prospective immunogenicity evaluation after receiving BNT162b2 or mRNA-1273. Participants were stratified by current CD4 T-cell count (poor CD4 recovery, PCDR: <200/mm³; intermediate CD4 recovery, ICDR: 200–500/mm³; high CD4 recovery, HCDR: >500/mm³). RBD-binding IgG, SARS-CoV-2 neutralizing antibodies (nAbs) and IFN-γ release were measured. As control group, HIV-negative healthcare workers (HCWs) were used

Findings

Among 166 PLWH, after 1 month from the booster dose, detectable RBD-binding IgG were elicited in 86.7% of PCDR, 100% of ICDR, 98.7% of HCDR, and a neutralizing titre ≥1:10 elicited in 70.0%, 88.2%, and 93.1%, respectively. Compared to HCDR, all immune response parameters were significantly lower in PCDR. After adjusting for confounders, current CD4 T-cell <200/mm3 significantly predicted a poor magnitude of anti-RDB, nAbs and IFN-γ response. As compared with HCWs, PCDR elicited a consistently reduced immunogenicity for all parameters, ICDR only a reduced RBD-binding antibody response, whereas HCDR elicited a comparable immune response for all parameters

Conclusion

Humoral and cell-mediated immune response against SARS-CoV-2 were elicited in most of PLWH, albeit significantly poorer in those with CD4 T-cell <200/mm³ versus those with >500 cell/mm³ and HIV-negative controls. A lower RBD-binding antibody response than HCWs was also observed in PLWH with CD4 T-cell 200–500/mm³, whereas immune response elicited in PLWH with a CD4 T-cell >500/mm³ was comparable to HIV-negative population

Pre-ART HIV-1 DNA in CD4+ T cells correlates with baseline viro-immunological status and outcome in patients under first-line ART

Objectives

We evaluated the association between pre-ART HIV DNA and HIV-infected participant characteristics at baseline as well as with their response to first-line ART.

Methods

Four hundred and thirty-three patients from the ICONA cohort, starting first-line ART after the year 2000, were analysed. Pre-ART HIV DNA was quantified with the modified COBAS TaqMan HIV-1 Test and normalized by CD4+ T cells. Linear correlation between pre-ART HIV DNA and other continuous markers (HIV RNA, CD4 count, markers of inflammation and coagulation) at baseline was evaluated by means of Pearson correlation coefficient and a linear regression model. Survival analyses and Cox regression models were used to study the association between pre-ART HIV DNA and time to viro-immunoclinical events.

Results

Pre-ART HIV DNA [median (IQR): 10 702 (3397-36 632) copies/106 CD4+ T cells] was correlated with pre-ART HIV RNA [R2 = +0.44, (P < 0.0001)], CD4+ T cells [R2 = -0.58, (P < 0.0001)] and CD4/CD8 ratio [R2 = -0.48, (P < 0.0001)], while weaker correlations were observed with CD8+ T cells (R2 = -0.20, P = 0.01), IL-6 (R2 = +0.16, P = 0.002) and soluble CD14 (R2 = +0.09, P = 0.05). Patients with higher pre-ART HIV DNA showed lower rate and delayed virological response (defined as HIV RNA ≤50 copies/mL), compared with those having lower HIV DNA (67.2% for >10 000, 81.1% for 1000-10 000 and 86.4% for 10-1000 copies/106 CD4+ T cells; P = 0.0004). Higher pre-ART HIV DNA was also correlated with increased risk of virological rebound (defined as HIV RNA >50 copies/mL) by 24 months (17.2% for >10 000, 7.4% for 1000-10 000 and 4.3% for 10-1000 copies/106 CD4+ T cells; P = 0.0048). Adjusted HRs of all virological rebound definitions confirmed these findings (P ≤ 0.02).

Conclusions

Pre-ART HIV DNA, along with HIV RNA and CD4+ T cell count, should be considered as a new staging marker to better identify people at lower (or higher) risk of viral rebound following achievement of virological suppression (≤50 copies/mL).

Inflammatory effects of atazanavir/ritonavir versus darunavir/ritonavir in treatment naïve, HIV-1-infected patients

BACKGROUND

Limited studies have compared the impact of different antiretroviral regimens on soluble markers of inflammation with discordant results.

METHODS

In this prospective study, treatment naïve HIV-1-infected patients were included if they started their current regimen with atazanavir/ritonavir (ATV/r) (N = 73, Group 1) or darunavir/ritonavir (DRV/r) (N = 85, Group 2) plus tenofovir/emtricitabine. The analysis of IL-6, MCP-1, sCD163, VCAM-1, ox-LDL, and adiponectine was performed on two stored plasma samples, the first prior to antiretroviral therapy initiation and the second one year after initiation.

RESULTS

The results of our analysis show a difference in ox-LDL between the two groups with higher mean (SD) values in ATV/r based group 608.5 ± 137.4 versus 519.1 ± 119.6 in DRV/r group, after controlling for baseline levels of ox-LDL as well as other potential confounding factors controlled by means of matching design or linear regression modelling.

CONCLUSIONS

Our analysis provides further data examining the association between the modulation of vascular inflammatory and of activation markers with specific protease inhibitors-based treatments over one year of exposure to these drugs. The data show little evidence for an association, supporting the notion that antiretroviral regimens has generally poor efficiency in downregulating these soluble markers.

Survival and predictors of death in people with HIV-associated lymphoma compared to those with a diagnosis of lymphoma in general population

OBJECTIVES

to compare overall survival in HIV-associated lymphoma (HIV-L) and lymphoma raising in HIV-negative population (nHIV-L) and to identify predictors of increased risk of death.

METHODS

All HIV+ patients with HIV-associated lymphoma (Hodgkin lymphoma, HL; non-Hodgkin Lymphoma, NHL) observed between 1.2000 and 12.2013 in the ICONA Foundation Study cohort or in three collaborating centres, and, as control group, nHIV-L individuals followed in one of the four collaborating centres over the same time period, were included. Survival estimates were calculated by use of Kaplan-Meier (KM) and multivariable Cox regression models.

RESULTS

1,331 pts were included (465 HIV-L, 866 nHIV-L): 909 (68%) NHL, 422 (32%) HL. 3 years-cumulative probability (95% confidence interval, CI) of death was higher in HIV-L compared to nHIV-L in NHL (38% (33-44) vs. 22% (19-26); p<0.001), and HL (22% [15-29] vs. 10% (6-13), p<0.001). Among HL, HIV was associated with an increased risk of death (hazard ratio [HR] = 2.37 [95% CI: 1.24-4.55], p = 0.009) independently of calendar year, age, gender, type of chemotherapy and stage; in NHL, HIV was no longer an independent predictor of death after controlling for rituximab use and IPI (HR = 1.26 (0.97-1.63), p = 0.08).

CONCLUSIONS

Our analysis shows a reduced overall survival in HIV+ patients diagnosed with lymphoma compared to HIV-negative controls. Whereas in HIV people with HL, the increased risk of death was confirmed even after adjustment for main confounders, the association between HIV status and survival in NHL appears to be somewhat attenuated after controlling for more aggressive presentation and lower frequency of rituximab use in HIV-+ people.

Switch of predicted HIV-1 tropism in treated subjects and its association with disease progression

Dynamics of human immunodeficiency virus type 1 (HIV-1) tropism after antiretroviral therapy (ART) initiation and their association with disease progression are poorly investigated.This was a cohort study on subjects from the ICONA cohort receiving ART with persistently detectable (PD) or persistently undetectable (PU) viral load (VL) and with stored plasma or peripheral blood mononuclear cell (PBMC) samples at 2 time-points (T1, T2) after ART initiation. HIV-1 co-receptor tropism was determined by V3-loop sequencing and the geno2pheno algorithm. A switch in viral tropism was defined if the tropism classification at T2 differed from that observed at T1. Time to disease progression, defined as the occurrence of a new acquired immune deficiency syndrome (AIDS)-defining event/death from T2, was also evaluated.One hundred ninety-five patients were analyzed (124 PD, 71 PU). Over a median follow-up of 22.6 (19.8-28.1) months, PD and PU patients showed similar rates (95% confidence interval) of switch to a non-R5 virus [PD: 6.9 (3.7-11.2)/100-person-years of follow-up (PYFU); PU: 8.0 (3.4-14.5)/100-PYFU; P = 0.63] and of switch to a R5 virus [PD: 15.4 (7.3-26.4)/100-PYFU; PU: 8.1 (2.5-16.7)/100-PYFU; P = 0.38]. Switch to non-R5 virus was predicted by nadir CD4+ before T1.Twenty-two (18%) PD and 4 (6%) PU subjects experienced disease progression (P = 0.02). The risk of disease progression was independently associated with a switch in co-receptor tropism (adjusted hazard ratio = 4.06, 95% CI: 1.20-13.80, P = 0.03) as well as age, AIDS diagnosis, nadir CD4+ before T2, current CD4+, and VL.Switch of HIV-1 tropism under ART occurs in both directions, with similar rates in subjects with PD or PU VL and it might be predictive of future unfavorable clinical outcome.

Evolution of HIV-1 tropism at quasispecies level after 5 years of combination antiretroviral therapy in patients always suppressed or experiencing episodes of virological failure

OBJECTIVES

Tropism evolution of HIV-1 quasispecies was analysed by ultra-deep pyrosequencing (UDPS) in patients on first-line combination antiretroviral therapy (cART) always suppressed or experiencing virological failure episodes.

METHODS

Among ICONA patients, two groups of 20 patients on cART for ≥5 years, matched for baseline viraemia and therapy duration, were analysed [Group I, patients always suppressed; and Group II, patients experiencing episode(s) of virological failure]. Viral tropism was assessed by V3 UDPS on plasma RNA before therapy (T0) and on peripheral blood mononuclear cell proviral DNA before-after therapy (T0-T1), using geno2pheno false positive rate (FPR) (threshold for X4: 5.75). For each sample, quasispecies tropism was assigned according to X4 variant frequency: R5, <0.3% X4; minority X4, 0.3%-19.9% X4; and X4, ≥20% X4. An R5-X4 switch was defined as a change from R5/minority X4 in plasma/proviral genomes at T0 to X4 in provirus at T1.

RESULTS

At baseline, mean FPR and %X4 of viral RNA were positively correlated with those of proviral DNA. After therapy, proviral DNA load significantly decreased in Group I; mean FPR of proviral quasispecies significantly decreased and %X4 increased in Group II. An R5-X4 switch was observed in five patients (two in Group I and three in Group II), all harbouring minority X4 variants at T0.

CONCLUSIONS

UDPS analysis reveals that the tropism switch is not an 'on-off' phenomenon, but may result from a profound re-shaping of viral quasispecies, even under suppressive cART. However, episodes of virological failure seem to prevent reduction of proviral DNA and to accelerate viral evolution, as suggested by decreased FPR and increased %X4 at T1 in Group II patients.

Is the CD4 Cell Percentage a Better Marker of Immunosuppression than the Absolute CD4 Cell Count in HIV-Infected Patients with Cirrhosis?

Recently, it was shown that cirrhotic patients without human immunodeficiency virus (HIV) infection had low CD4 cell counts and normal CD4 cell percentages, suggesting that, for HIV-infected persons, the CD4 cell percentage might be a more accurate marker of disease progression than the absolute CD4 cell count. In cirrhotic HIV-infected persons in the Italian Cohort of Antiretroviral-Naive Patients, the absolute CD4 cell count seemed to be better predictor of the risk of developing an acquired immunodeficiency syndrome-defining illness than the CD4 cell percentage.

Is moderate HIV viremia associated with a higher risk of clinical progression in HIV-infected people treated with highly active antiretroviral therapy: evidence from the Italian cohort of antiretroviral-naive patients study

OBJECTIVE

To assess the risk of clinical progression (CP) according to the duration of time spent without complete viral load (VL) suppression compared with that associated with periods of stably suppressed viremia in HIV-infected people who started highly active antiretroviral therapy (HAART) when previously naïve to antiretrovirals.

DESIGN

A cohort study of patients having started HAART after enrollment in the Italian Cohort of Antiretroviral-Naive Patients (ICoNA) and being followed for at least 6 months.

METHODS

Person-years spent in different categories according to the VL level and the change in VL from the most recent value before the initiation of HAART were calculated. A multivariable Poisson regression model, including potential confounders, was constructed.

RESULTS

A total of 3023 patients were studied. The overall rate of CP was 13.4 per 1000 person-years. Evidence for a higher risk of CP was observed for people with a current VL >10,000 copies/mL. For each year longer spent on HAART with a VL >100,000 copies/mL, a 5-fold increased risk was observed (relative risk [RR] = 5.34, 95% confidence interval [CI]: 2.83 to 1.08; P = 0.0001). An increased risk of CP in patients with current suppression <1.5 log10 copies/mL (RR = 2.34, 95% CI: 1.16 to 4.74; P = 0.02) and in those with no suppression or a VL higher than their set point (RR = 2.39, 95% CI: 1.17 to 4.89; P = 0.02) was observed compared with those with suppression of >3 log10 copies/mL, although it was not significant. Longer duration on HAART with a VL suppressed below set point seemed to confer protection against CP.

CONCLUSIONS

Virologic failure to antiretroviral drugs is common. The risk of CP may remain low despite a low but detectable level of HIV viremia.

Access to Antiretroviral Treatment, Incidence of Sustained Therapy Interruptions, and Risk of Clinical Events According to Sex

Objectives of the study were to assess the differences between sexes in the likelihood of starting antiretroviral therapy (ART), in rates of sustained discontinuation from highly active antiretroviral therapy (HAART), and in clinical progression. In a multicenter cohort study (I.Co.N.A. Study), 2323 men and 1335 women previously naive to antiretrovirals were enrolled. As of September 2002, 807 women and 1480 men started ART. The median time to starting ART was 28 weeks for women and 17 weeks for men (P = 0.0003 by log-rank test). This difference was no longer significant after adjusting for either HIV RNA (P = 0.21) or CD4 count (P = 0.28) at enrollment. Women tend to start HAART less frequently than mono/dual ART after adjusting for potential confounders (odds ratio = 0.78, 95% confidence interval [CI]: 0.60-1.01; P = 0.06). Women who started HAART were 1.4 times more likely than men (95% CI: 1.00-1.99; P = 0.05) to interrupt at least 1 drug because of toxicity. Twenty-one percent of women and 19% of men interrupted HAART altogether for more than 3 months (P = 0.3). Clinical progression was observed in 53 women (22.6%) and 137 men (23.4%; P = 0.56). Risk of developing a clinical event was found to be no different between women and men (relative hazard = 0.84, 95% CI: 0.56-1.26; P = 0.40).

Definition of loss of virological response in trials of antiretroviral drugs

Definition of the time of loss of virological response is important when designing a viral load endpoint for trials of antiretroviral drugs. We assessed whether, in patients who achieved a viral load below 50 copies/ml, two consecutive values above 50 copies/ml was really indicative of loss of response. It was common for the viral load to return to below 50 copies/ml with no change in regimen, suggesting that a higher threshold for defining the loss of response is required.

Theoretical rationale for the use of sequential single-drug antiretroviral therapy for treatment of HIV infection

BACKGROUND

Subpopulations of HIV with mutations associated with resistance to antiretroviral drugs often have reduced replicative capacity, so virus with resistance mutations for all existing and new antiretroviral drugs is likely to be appreciably impaired. Issues of toxicity, quality of life and economics mean that the simultaneous use of all these drugs in combination is unrealistic. We aimed to explore the use of sequential monotherapy regimens using a mathematical model of quasi-species dynamics, to see if these could take advantage of the poor replicative capacity of highly resistant virus.

METHODS

We assume for each of seven drugs that a single mutation is associated with the ability to replicate (effective reproductive ratio, R > 1) in the presence of that drug as monotherapy. Parameters included were drug efficacy, the cost of resistance mutations and the number of new target cells arising daily.

RESULTS

The use of seven drugs in a daily/weekly sequential monotherapy cycle led to substantial viral suppression (in the presence of all resistant viral subpopulations) for a wider range of parameter values than a continuous five-drug regimen. Although on any one day/week there is a viral subpopulation with R > 1 (e.g. that with resistance only to the current drug), this subpopulation does not have time to grow sufficiently during the short period when that drug is being taken.

CONCLUSION

These results provide a rationale for trials of sequential regimens, using as wide a number of drugs with different resistance-associated mutations as possible, as a potential 'resistance-proof' strategy for achieving significant viral load suppression.

Coinfection with hepatitis viruses and outcome of initial antiretroviral regimens in previously naive HIV-infected subjects

BACKGROUND

The effect of chronic coinfection with hepatitis viruses on the response to therapy against human immunodeficiency virus 1 (HIV-1) remains debated.

METHODS

In a prospective cohort study, the effect of hepatitis B virus (HBV) and hepatitis C virus (HCV) serostatus on the outcome of potent HIV-1 therapy was analyzed in HIV-1-infected patients previously naive to antiretroviral therapy. Changes from baseline CD4+ cell counts and HIV RNA levels over time were analyzed by linear regression models. Time to clinical progression and time to reach virologic and immunologic response were analyzed by multivariate Cox proportional hazards regression models.

RESULTS

We studied 1320 patients, among whom 600 were HCV antibody-positive and 90 were HBV surface antigen-positive. During a median follow-up of 37 months (range, 1-48 months), clinical progression was observed in 99 patients (56 new acquired immunodeficiency syndrome-defining events and 43 deaths). In multivariate models, HCV-positive HBV-negative patients showed a shorter time to clinical progression (hazard ratio, 1.55; 95% confidence interval, 1.00-2.41). Patients who were HCV-positive also showed mean CD4+ recoveries over time that were at least 30 cells/ micro L fewer than those of seronegative patients. Hepatitis virus serostatus did not affect the virologic response to HIV-1 therapy.

CONCLUSIONS

Clinical progression of HIV-1 disease after starting potent antiretroviral therapy is accelerated by concomitant infection with HCV. Compared with patients without coinfection, coinfected patients showed impaired CD4+ cell recovery, despite similar virologic response to HIV-1 therapy. These findings may have important implications for the treatment of HCV and for the timing of initiation of HIV-1 therapy in coinfected individuals.

Relationships among the detection of p24 antigen, human immunodeficiency virus (HIV) RNA level, CD4 cell count, and disease progression in HIV-infected individuals with hemophilia

The aim of this study was to assess the relationships among the detection of p24 antigen, human immunodeficiency virus (HIV) RNA level, CD4 cell count, and disease progression in 111 males with hemophilia who were infected with HIV for < or =20 years. Sixty-four individuals (58%) developed p24 antigenemia a median of 11.6 years after seroconversion. The time to first detection of p24 antigen was shorter among those who were older (P=.04) and those with a high initial HIV RNA level (P=.006). The median HIV RNA level and CD4 cell count at the time of the detection of p24 antigen were 4.95 log(10) copies/mL and 100 cells/mm(3), respectively. In univariate analyses, p24 antigenemia was associated with more-rapid progression to AIDS (relative hazard [RH], 5.50; P=.0001). The effect was reduced (RH, 1.85; P=.06) after adjusting for CD4 cell counts and HIV RNA levels during follow-up, age, and calendar year. A significant relationship between p24 antigenemia and death was nonsignificant after adjusting for CD4 cell count.

Prognostic value of single measurements of beta-2-microglobulin, immunoglobulin A in HIV disease after controlling for CD4 lymphocyte counts and plasma HIV RNA levels

The interrelationships between the CD4 lymphocyte count, plasma viral load [human immunodeficiency virus (HIV) RNA], beta-2-microglobulin (beta2-M) and immunoglobulin A (IgA) and the mortality risk was explored in 234 HIV-infected individuals (median CD4 count 230 cells/mm3, range 1-1,247). Product-moment correlation analysis was used to study the association between beta2-M, IgA and HIV RNA. A proportional hazards Cox model was used to estimate the relative hazard (RH) of death. Both beta2-M (r = 0.49, p < 0.0001) and IgA (r = 0.42, p < 0.0001) were positively correlated with HIV RNA. High beta2-M levels were associated with an increased risk of death in both univariate Cox analysis and after adjustment for HIV RNA, CD4 lymphocyte count and age [RH = 1.16 per 100 nmol/l higher beta2-M, 95% confidence interval (CI) 1.05-1.27]. Raised IgA levels were associated with shorter survival in individuals with a CD4 count above 50 cells/mm3 in univariate analysis as well as after adjusting for age and CD4 lymphocyte count (RH = 1.19 per 10 micromol/l higher IgA, 95% CI 1.01-1.39). However, this association was no longer significant after further adjusting for HIV RNA. In conclusion, beta2-M levels provided additional prognostic information for survival to the information obtained by CD4 count and HIV RNA levels, whereas serum IgA only was a weak prognostic marker in this fairly progressed cohort.

Reasons for modification and discontinuation of antiretrovirals: results from a single treatment centre

OBJECTIVE

To describe the reasons for, and factors associated with, modification and discontinuation of highly active antiretroviral therapy (HAART) regimens at a single clinic.

SUBJECTS

A total of 556 patients who started HAART at the Royal Free Hospital were included in analyses. Modification was defined as stopping or switching any antiretrovirals in the regimen, whereas discontinuation was defined as the simultaneous stopping of all antiretrovirals included in the initial regimen. Reasons were classified as immunological/virological failure (IVF) and toxicities and patient choice/poor compliance (TPC).

RESULTS

The median CD4 count at starting HAART was 171 x 10(6) cells/l and viral load 5.07 log copies/ml. During a median follow-up of 14.2 months, 247 patients (44.4%) modified their HAART regimen, 72 due to IVF (29.1%) and 159 due to TPC (64.4%) and a total of 148 patients (26.6%) discontinued HAART. Older patients were less likely to modify HAART [relative hazard (RH), 0.73 per 10 years; P = 0.0008], as were previously treatment-naive patients (RH, 0.65; P = 0.0050), those in a clinical trial (RH, 0.64; P = 0.027) and those who started nelfinavir (RH, 0.57; P = 0.035). Patients who started with four or more drugs (RH, 2.21, P < 0.0001), who included ritonavir in the initial regimen (RH, 1.41; P = 0.035) or who had higher viral loads during follow-up (RH per log increase, 1.51; P < 0.0001) were more likely to modify HAART.

CONCLUSIONS

There was a high rate of modification and discontinuation of HAART regimens in the first 12 months, particularly due to toxicities, patient choice or poor compliance.

The virological response to highly active antiretroviral therapy over the first 24 weeks of therapy according to the pre-therapy viral load and the weeks 4-8 viral load

OBJECTIVES

To describe the viral response to HAART by weeks 4 and 8 in previously antiretroviral-naive patients. To assess whether the weeks 4 or 8 viral loads are useful predictors of viral suppression by week 24.

DESIGN

A large clinical database including 453 antiretroviral-naive patients whose plasma viral load was monitored every 4 weeks.

METHODS

Observed probabilities of achieving a viral load < or = 500 copies/ml by week 24 (days 84-168) from starting highly active antiretroviral therapy (HAART) were calculated according to viral loads at weeks 4 and 8.

RESULTS

A total of 42.4% of patients (153/361) reached < or = 500 copies/ml viral load by week 4 and 70.4% (245/348) by week 8. Viral suppression below 500 copies/ml by 4-8 weeks was similar irrespective of the pre-HAART viral load. In patients with viral loads above 10000 copies/ml at week 4, 60.6% (20/33) achieved < or = 500 copies/ml by week 24. In patients with viral loads still above 10000 copies/ml at week 8, only 42.3% (11/26) achieved < or = 500 copies/ml by week 24, and only 33.3% (3/9) maintained viral suppression below 500 copies/ml to week 48.

CONCLUSION

Viral loads at weeks 4 and 8 should be monitored to detect early signs of low subsequent viral suppression. For previously antiretroviral-naive patients whose viral loads after 8 weeks of HAART are still above 10000, there is an urgent need to assess adherence to therapy, drug levels and resistance, so management can be modified accordingly to reduce the rate of week 24 virological failure.

Serum level of soluble urokinase-type plasminogen activator receptor is a strong and independent predictor of survival in human immunodeficiency virus infection

Human immunodeficiency virus-1 (HIV-1) infection has been shown to result in up-regulation of the urokinase-type plasminogen activator receptor (uPAR/CD87) on leukocytes in vitro and in vivo. The objective of this study was to investigate whether this up-regulation is paralleled by higher serum levels of soluble uPAR (suPAR) in patients with advanced HIV-1 disease and whether the serum level of suPAR is predictive of clinical outcome. Using an enzyme-linked immunosorbent assay, the level of suPAR was measured retrospectively in serum samples from 314 patients with HIV-1 infection. By Kaplan-Meier and Cox regression analyses, the serum suPAR levels were correlated to survival with AIDS-related death as the end point. High levels of serum suPAR (greater than median) were associated with poor overall survival, and Kaplan-Meier analysis on patients stratified by suPAR level demonstrated a continuous increase in mortality rates with higher suPAR levels. After adjustment for accepted prognostic markers-including Centers for Disease Control and Prevention-defined clinical stages, CD4 counts, viral load, beta2-microglobulin, and age-the prognostic strength of suPAR remained highly significant, indicating that the serum suPAR level is a novel, strong, and independent predictor of survival in HIV-1 infection. This report is the first to demonstrate an important association between the plasminogen activator system and disease progression in HIV-1 infection.

A practical guide to applying the intention-to-treat principle to clinical trials in HIV infection

It is recommended that randomized controlled trials be analyzed on an intention-to-treat (ITT) basis whereby patients are analyzed in the group to which they were originally assigned, irrespective of the treatment actually received. However, in trials of antiretroviral therapy, it is quite common for patients to withdraw from the trial, and information on virological or immunological endpoints may not be available. The way in which this missing information is dealt with in the analysis can have a large effect on the results of a trial and, therefore, the principle of ITT may be adhered to more closely in some studies than in others. This article describes some simple approaches commonly taken to impute missing data values and discusses the possible effects of these approaches on the results of a trial.

Plasma viral load concentrations in women and men from different exposure categories and with known duration of HIV infection. I.CO.N.A. Study Group

CONTEXT

According to recent studies, women have lower plasma HIV RNA concentrations than men. However, these studies did not take into account the duration of HIV infection.

OBJECTIVES

To analyze the relationship between viral load and gender among individuals with known date of seroconversion.

SETTING

Sixty infectious disease clinics in Italy.

DESIGN

Cross-sectional analysis of data collected at enrollment in a cohort study.

PARTICIPANTS

Injecting drug users and heterosexual contacts naive to antiretroviral therapy at enrollment (245 men; 170 women).

MAIN OUTCOME MEASURES

Plasma HIV RNA concentrations, measured using quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) or signal amplification b-DNA assays before antiretroviral therapy.

RESULTS

Plasma HIV RNA concentrations were similar by age and exposure category (p =.80 and p =.39, respectively). Median viral load among women was roughly half that of men (p =.002). The association between viral load and gender remained significant after fitting a two-way analysis of variance (p =.03) and after adjusting for CD4 count, modality of HIV transmission, and age at enrollment in a regression model. Viral load was 0.27 log10 copies/ml (95% confidence interval, 0.05-0.40; p =.01) lower in women (i.e., 50% lower in the raw scale).

CONCLUSIONS

Plasma HIV RNA concentrations were found to be lower among women, even when considering the duration of HIV infection. Compared with men, it is possible women should be given highly aggressive antiretroviral therapy at lower HIV-RNA concentrations.

Insights into the reasons for discontinuation of the first highly active antiretroviral therapy (HAART) regimen in a cohort of antiretroviral naïve patients. I.CO.N.A. Study Group. Italian Cohort of Antiretroviral-Naïve Patients

OBJECTIVE

To evaluate the frequency of discontinuation of the first highly active antiretroviral regimen (HAART) and the factors predictive of discontinuing for toxicity and failure in a population-based cohort of HIV-positive individuals in Italy, naïve from antiretrovirals at enrolment.

METHODS

The study population consisted of individuals who initiated HAART and had at least one follow-up visit. The primary end-points were discontinuation of any component of HAART for drug toxicity and discontinuation for failure. Survival analyses were performed to identify predictive factors for reaching the two end-points.

RESULTS

Eight hundred and sixty-two individuals initiated HAART; in 727 of them (84.3%) this consisted of two nucleoside reverse transcriptase inhibitors (NRTI) and one protease inhibitor (PI). Over a median follow-up of 45 weeks, 312 patients (36.2%) discontinued therapy: 182 (21.1%) discontinued due to toxicity, 44 (5.1%) due to failure. The probability of discontinuing HAART at 1 year was 25.5% [95% confidence interval (CI), 21.9-28.9] due to toxicity and 7.6% (95% CI, 4.9-1 0.3) due to failure. Independent factors associated with discontinuation for toxicity were: gender [relative hazard (RH) = 0.51; 95% CI, 0.32-0.80 for men versus women], type of treatment (indinavir-containing regimens, RH = 1.94; 95% CI, 1.10-3.41 and ritonavir-containing regimens, RH = 3.83; 95% CI, 2.09-7.03 versus hard-gell saquinavir) and time spent on treatment (RH = 0.89; 95% CI, 0.80-0.98 for each additional month). Discontinuation due to failure was independently associated with the most recent HIV-RNA (RH = 3.20; 95% CI, 1.74-5.88 for log10 copies/ml higher), and with type of treatment (indinavir-containing regimens, RH = 0.21; 95% CI, 0.06-0.78 and ritonavir-containing regimens, RH = 0.23; 95% CI, 0.04-1.26 versus hard-gell saquinavir).

CONCLUSIONS

If the current HAART regimen caused no toxicity, less than 10% of naïve patients discontinue their first HAART regimen because of failure after 1 year from starting therapy.

Risk factors for HTLV-I and II in individuals attending a clinic for sexually transmitted diseases

BACKGROUND

To date, few studies have provided information on risk factors for human t-lymphotropic viruses (HTLV) types I and II in European countries. In particular, few data are available from published studies conducted in STD centers.

GOALS

To identify risk factors for HTLV-I and HTLV-II infection and to better distinguish the epidemiologic patterns of the two viruses in Italy.

STUDY DESIGN

A cross-sectional study of individuals at high risk of sexually or parenterally transmitted infections attending a large STD center in an urban setting was conducted. Serologic tests for HTLV-I and II, HIV, hepatitis virus type B (HBV), hepatitis virus type C (HCV), and syphilis were performed. Information regarding at-risk behavior was collected using a specific questionnaire.

RESULTS

From January 1994 to June 1996, 1,457 individuals were recruited; of them, 1,016 (69.7%) were males, 1,051 (72.4%) Italians, and 288 (19.8%) non-Europeans. One thousand seventy-five (74.8%) participants were noninjecting-drug-using heterosexuals, 285 (19.6%) were men who have sex with men, and 97 (6.6%) were injecting drug users (IDU). The mean age of the study participants was 33.6 (+/-10.5) years. Nine (0.6%) individuals were positive for HTLV-I antibodies and 9 (0.6%) for HTLV-II antibodies. The prevalence of HTLV-I among IDUs, men who have sex with men, and noninjecting-drug-using heterosexuals, was 2.1% (2/97), 1.4% (4/ 285), and 0.3% (3/1085), respectively. HTLV-II prevalence was 8.2% (8/97) among IDUs and 0.09% (1/1075) among noninjecting-drug-using heterosexuals. Among the nine HTLV-II-positive individuals, eight were Italian IDUs and one was a noninjecting-drug-using heterosexual man from India. None of the 285 men who have sex with men had HTLV-II antibodies. HTLV-infected individuals tended to be older than those who were uninfected. HTLV-I-infected individuals were more likely to be non-European and to have antibodies against Treponema pallidum. Injecting drug use tended to be independently associated with HTLV-II infection.

CONCLUSIONS

The data suggest a role of sexual behavior in the spread of HTLV-I, which is more likely to be detected in individuals coming from endemic areas. Injecting drug use remains the most important risk factor for HTLV-II infection in Italy.

The spectrum of AIDS-defining diseases: temporal trends in Italy prior to the use of highly active anti-retroviral therapies, 1982-1996

OBJECTIVE

To evaluate time trends of the spectrum of AIDS-defining diseases in Italy, 1982-1996.

METHODS

Surveillance data from the Italian National AIDS Registry were used to assess temporal patterns of all AIDS-defining diseases diagnosed among adults as of December 1996. Twenty-six initial clinical manifestations of AIDS were grouped into 12 categories. Relative frequencies were calculated by year of diagnosis and stratified by age, gender, HIV-exposure category, and CD4+ cell count. A multivariate polychotomous logistic model was used to estimate the proportions of each diagnostic category over time, adjusting simultaneously for the remaining diagnostic categories and for variables of interest.

RESULTS

This analysis was based on 41772 diagnoses of AIDS-defining diseases among 36 638 reported cases. Mycoses represented the most frequent condition (27.3%), followed by Pneumocystis carinii pneumonia (PCP) (21.4%) and viral infections (8.9%). Cancers accounted for less than 10% of diseases. Downward trends were observed for mycoses, PCP (in the last part of the study period), Kaposi's sarcoma (KS), and non-Hodgkin's lymphomas (NHL). Upward trends were observed for mycobacterioses, and bacterial and protozoal infections. Brain toxoplasmosis increased up to 1994, and, thereafter, it appeared to decrease. These trends were less marked when the analysis was restricted to the diseases included in the pre- 1987 AIDS definition. Trends stratified by CD4+ cell count for the period 1990-1996 were substantially consistent with the above-reported results.

CONCLUSIONS

The downward temporal trends in the most recent years of the study period for PCP and for brain toxoplasmosis are likely to be related to the use of prophylactic treatment. This analysis confirms a decline in KS but suggests that this was largely over by 1990.

Bulk culture levels of specific cytotoxic T-cell activity against HIV-1 proteins are not associated with risk of death

The ability of cytotoxic T lymphocytes (CTL) to control and influence the outcome of human immunodeficiency virus (HIV) infection is not fully understood. The association between HIV-CTL activity and disease progression was evaluated prospectively in 36 HIV-1-infected individuals with a median follow-up of 3.0 years. HIV-CTL activity was measured in a 4 h Cr* release assay using autologous target cells expressing HIV-1 BRU isolate gene products (gp-120, gag, pol, nef) and a bulk culture of autologous effector cells. The CD4 count was measured at enrolment and plasma HIV RNA was measured retrospectively. The present study failed to support the hypothesis that HIV-CTL activity, as measured using the present method, is important in reducing the risk of death in HIV-infected individuals. However, using other approaches and methods could possibly yield other conclusions, and further prospective studies are needed to examine the relationship between CTL and disease progression.

CD4 lymphocyte count as a predictor of the duration of highly active antiretroviral therapy-induced suppression of human immunodeficiency virus load

The association between CD4 cell count and duration of virus load suppression was investigated in 558 patients in the Frankfurt HIV Clinic Cohort who had begun highly active antiretroviral therapy and who had virus load declines to </=500 copies/mL. The Kaplan-Meier method estimated viral rebound in 42.5% of patients by 24 weeks and in 64.3% by 84 weeks. Risk of viral rebound was independently associated with baseline and changes from baseline CD4 cell count. The achieved CD4 cell count was the most important factor for prediction of viral rebound (relative hazard, 5.4 for an updated CD4 cell count of <20 vs. >500 copies/mL; P=.0001). Baseline virus load was not associated with virus load rebound. Lower baseline CD4 cell counts were associated with increased risk of viral rebound; however, this risk was significantly reduced in persons with low baseline CD4 cell counts who experienced substantial increases in CD4 cell counts during follow-up.

The changing pattern of admissions to a London hospital of patients with HIV: 1988-1997. Royal Free Centre for HIV Medicine

OBJECTIVE

To describe the changes over time in incidence of hospital admissions among patients with HIV, reasons for hospital admission, duration of stay, relationship with CD4 T-cell count and with antiretroviral treatment.

METHODS

The incidence of hospital admissions during each calendar year from 1988 to 1997 inclusive was calculated using a person-years analysis. In addition the proportion of patient follow-up spent in hospital and the impact of changing treatment regimens among all patients with HIV aged > or = 14 years and with at least one CD4 T-cell count seen at the Royal Free Hospital, London was also described.

RESULTS

A total of 1806 patients were investigated with median follow-up of 21.1 months. Among all patients, the proportion of follow-up time spent as an in-patient decreased from 3.9% in 1988 to 1.3% in 1997 (P = 0.0015; test for trend). Hospital admissions for any cause peaked during 1989 at 72.0 per 100 patient years of follow-up (PYFU) and was 28.5 per 100 PYFU during 1997 (P < 0.0001; test for trend). There was a statistically significant decline in the proportion of follow-up time spent as an in-patient among patients with CD4 T-cell counts of < 50 x 10(6)/l from > 30% before 1990 to < 5% during 1997 (P = 0.026; test for trend). Hospital admissions varied greatly according to treatment regimen; in 1996 and 1997 just 0.1% of follow-up time of patients on triple antiretroviral treatment regimens was spent as a hospital admission.

CONCLUSIONS

Admissions to hospital began falling before the introduction of combination therapy and declined strikingly during 1996 and 1997 following the introduction of highly active antiretroviral therapy. These results have important implications for future allocation of resources and for patient management.

The influence of nutritional and metabolic status on progression from asymptomatic HIV infection to AIDS-defining diagnosis

BACKGROUND

Changes in body weight and lean tissue increase morbidity and mortality during AIDS; however there are few data on the effect of alterations in nutrition and metabolism on disease progression at earlier stages of HIV infection.

OBJECTIVES

To assess whether change in weight, lean tissue or skeletal muscle affects progression to AIDS; to assess prospectively the effects of recognized alterations in nutrition and metabolism in asymptomatic HIV-seropositive men on disease progression; and to examine prospectively changes in nutrition and metabolism at AIDS-defining diagnosis.

METHODS

A group of 104 asymptomatic HIV-seropositive men were recruited and prospectively examined at 3-monthly intervals between April 1993 and September 1995. Nutritional status and metabolism were examined using indirect calorimetry, dual energy X-ray absorptiometry and urine excretion of simple sugars. Time-fixed and time-dependent Cox's proportional hazard models were fitted to calculate risks of developing a first AIDS diagnosis, weight loss or death.

RESULTS

During the study period, 31 subjects had a first AIDS diagnosis of whom 26 were fully assessed. Changes in nutrition and metabolism do not affect disease progression in asymptomatic HIV infection. However, subjects with a reduction in body weight and basal metabolic index tend to have a higher risk of progression to AIDS-defining diagnosis, independent of CD4 count. There is a significant decrease in all body tissue compartments, a decrease in excretion of urinary sugars and significant increase in resting energy expenditure and fat oxidation associated with a first AIDS diagnosis.

CONCLUSION

Change in metabolic and nutritional status at the asymptomatic stage of HIV infection does not influence disease progression significantly, although there is a trend suggesting weight loss has an independent effect on outcome. There is a cachectic response to AIDS-defining opportunistic infection or tumour.

Increased losses of CD4+CD45RA+ cells in late stages of HIV infection is related to increased risk of death: evidence from a cohort of 347 HIV-infected individuals

OBJECTIVE

To examine changes in the distribution of CD4+CD45RA+ (naive) and CD4+CD45RO+ (memory) lymphocytes in various stages of HIV infection and the effect of these changes on disease progression.

DESIGN AND METHODS

Expression of CD45RA+ and CD45RO+ on CD4+ lymphocytes was analysed by flow cytometry in a prospectively followed cohort of 300 HIV-infected individuals (median follow-up time, 2.90 years; range, 0.02-4.54 years) and in a group of 102 age- and sex-matched uninfected controls. Survival analysis was performed considering AIDS development and death as endpoints.

RESULTS

The median CD4+CD45RA+/CD45RO+ ratio was 1.3 (25-75% quartiles, 0.9-2.4) in controls; it was increased to 1.8 (1.1-2.5) in 40 HIV-infected individuals with CD4+ cell counts > 500 x 10(6)/l (P < 0.05); it was similar at 1.4 (0.8-2.0) in 106 HIV-infected individuals with CD4+ cell counts of 200-500 x 10(6)/l; and it was decreased to 0.9 (0.5-1.4) in 154 HIV-infected individuals with CD4+ cell counts < 200 x 10(6)/l (P < 10[-6]). When fitted in a Cox model adjusting for the total number of CD4+ cells and age a lower concentration of CD4+CD45RA+ cells was associated with an increased risk of dying. The concentration of CD4+CD45RO+ cells was not significantly associated with AIDS or death in age- and CD4+ cell count-adjusted Cox models.

CONCLUSIONS

This study confirms a selective loss of memory CD4+ cells early in HIV infection followed by increased loss of naive CD4+ cells in later stages of the infection. The loss of naive CD4+ cells seems to be important in the pathogenesis of terminal HIV infection.

Incidence and determinants of hepatitis C virus infection among individuals at risk of sexually transmitted diseases attending a human immunodeficiency virus type 1 testing program

BACKGROUND

The role of sexual transmission of hepatitis C virus (HCV) infection is still not completely understood, partly because of the lack of longitudinal studies among cohorts of HCV-negative individuals who engage in at-risk sexual behavior.

GOALS

To evaluate the incidence of HCV infection in a population at risk for human immunodeficiency virus type 1 (HIV-1) infection and other sexually transmitted diseases (STD) and to identify factors associated with HCV seroconversion.

STUDY DESIGN

A retrospective longitudinal study was carried out on a cohort of consecutive attendees of a voluntary HIV-1 testing and counseling program in a large STD center in Rome. All individuals undergoing at least two consecutive tests for HCV antibodies were enrolled. Clinical data and information on individual behavior were collected for all study participants.

RESULTS

Between June, 1992 and December, 1994, a total of 709 individuals (12 intravenous drug users [IDU], 244 homosexuals, and 453 heterosexual non-IDUs), initially negative for HCV antibody, were tested more than once. Among these individuals, 15 HCV seroconversions occurred. The average follow-up time was 1.25 person/years (p/y) for an incidence rate of 1.69 per 100 p/y. The incidence rates by exposure category were 39.30 per 100 p/y among IDUs, 1.37 per 100 p/y among homosexual men, and 0.97 per 100 p/y among heterosexual non-IDUs. Excluding IDUs, of the 697 STD clinic attendees engaging in at-risk sexual behavior, HIV-1-positive status tended to be associated with HCV seroconversion (relative hazard = 5.48; 95% confidence interval = 0.85-35.40). The HCV crude incidence rates among HIV-1-infected patients at enrollment was 11.5%, 4.2%, and 2.4% in those with severe, moderate, and mild levels of immunosuppression, respectively (chi-square for trend = 2.38, P = 0.1).

CONCLUSIONS

In this cohort, HCV infection was confirmed to be strongly associated with intravenous drug use. Nonetheless, the occurrence of two thirds of the total HCV seroconversions in non-IDU individuals engaging in at-risk behavior suggests a role of sexual practices in the transmission of the infection. Among non-IDU individuals, the risk for development of HCV infection tended to increase in those who were HIV-1 infected.

Is there a general tendency for CD4 lymphocyte decline to speed up during human immunodeficiency virus infection? Evidence from the Italian Seroconversion Study

It has been suggested that the rate of CD4 cell decline accelerates in parallel with decreasing numbers of cells; however, the statistical literature suggests the opposite. CD4 cells were counted about every 6 months in a cohort of 1264 human immunodeficiency virus-infected subjects (the Italian Seroconversion Study cohort). Kaplan-Meier analysis was used to estimate the time for CD4 cells to decline by 100 cells/mm3, conditional on reaching predefined levels. In addition, CD4 cell counts were modeled as a function of time since seroconversion in individuals with > or = 5 counts. Kaplan-Meier survival times for a 100 cell/mm3 decrease in CD4 cells increased as lower counts were reached (log rank test, P < .001). The shape of the overall fitted curve of the CD4 cell counts does not suggest an increasing rate of decline. Data from the Italian Seroconversion Study cohort do not show a general tendency for accelerating CD4 cell decline in association with lower counts.

Energy balance in asymptomatic HIV infection

OBJECTIVES

Body weight is regulated by the balance between energy intake and energy expenditure, but the influence of HIV infection on energy balance has not been fully examined. The main objectives of this study were (1) to assess the effect of HIV on energy balance, (2) to examine the relationship of parameters of immunodeficiency to energy balance, and (3) to examine the interrelationship of different components of energy balance in asymptomatic HIV-seropositive men.

DESIGN

A cross-sectional study of nutrition and metabolism in asymptomatic HIV-seropositive men

METHODS

Components of energy balance were examined in 104 asymptomatic HIV-seropositive men (CD4 count 4-482 x 10(6)/l) and 57 age-matched HIV-seronegative male controls. Energy and protein intake were measured using 5-day diaries, and small bowel absorption and permeability was assessed using four sugar probes. Resting energy expenditure was calculated from indirect calorimetry and nitrogen loss estimated from 24 h urine collection. Four methods were used to assess the effect of HIV infection on body composition (anthropometry, dual energy X-ray absorptiometry, bioelectrical impedance and 24 h urine creatinine).

RESULTS

Resting energy expenditure per kilogram of fat-free mass was raised (P < 0.0001), fat mass was decreased (P = 0.001), fat-free mass was increased (P = 0.05), energy intake was higher (P = 0.05), absorption of L-rhamnose (P = 0.01) and 3-O-methyl-D-glucose was decreased (P = 0.003), and small bowel permeability was increased (P < 0.0001) in HIV-seropositive men compared with HIV-seronegative controls. HIV-seropositive subjects with a CD4 count less than 100 x 10(6)/l had decreased absorption of L-rhamnose (P < 0.05), D-xylose (P < 0.05) and 3-O-methyl-D glucose (P < 0.05) compared with HIV-seropositive subjects at higher CD4 counts, and had a similar resting energy expenditure to HIV-seronegative controls. Protein intake, carbohydrate, fat and protein oxidation. 24 h nitrogen excretion and appendicular muscle mass were similar in HIV-seropositive men and controls.

CONCLUSION

HIV infection exerts a direct effect on parameters of energy balance that varies with the severity of immunosuppression.

Category of exposure to HIV and age in the progression to AIDS: longitudinal study of 1199 people with known dates of seroconversion. HIV Italian Seroconversion Study Group

OBJECTIVES

To determine whether rate of development of AIDS is affected by category of exposure to HIV and whether the more rapid development found in older subjects persists for each exposure category.

DESIGN

Longitudinal study of people with known date of seroconversion to HIV.

SETTING

16 HIV treatment centres throughout Italy.

SUBJECTS

1199 people infected with HIV through use of injected drugs, homosexual sex, or heterosexual sex.

MAIN OUTCOME MEASURES

AIDS as defined by 1987 definition of Centers for Disease Control (including and excluding neoplasms) and by 1993 European definition.

RESULTS

225 subjects (18.8%) progressed to AIDS (Centers for Disease Control 1987 definition) during median follow up of 5.8 years. Univariate analyses showed more rapid progression to AIDS for older subjects compared with younger subjects and for homosexual men compared with other exposure categories. The age effect was of similar size in each exposure category and in men and women. In a bivariate model with age and exposure categories simultaneously included as covariates, differences by exposure category disappeared for use of injected drugs and heterosexual sex compared with homosexual sex (relative hazards 1.02 (95% confidence interval 0.71 to 1.45) and 1.07 (0.70 to 1.64) respectively), while the age effect remained (relative hazard 1.55 (1.32 to 1.83) for 10 year increase in age). Analyses using the other definitions for AIDS did not appreciably change these results.

CONCLUSIONS

There was no evidence of differences in rate of development of AIDS by exposure category, while there was a strong tendency for more rapid development in older subjects for all three groups. This supports the view that external cofactors do not play major role in AIDS pathogenesis but that age is of fundamental importance.

Community-acquired pneumonia in a cohort of former injection drug users with and without human immunodeficiency virus infection: incidence, etiologies, and clinical aspects

Although the association among bacterial pneumonia, human immunodeficiency virus (HIV) infection, and injection-drug use seems to have been well established, accurate estimates of the risk of community-acquired pneumonia among HIV-positive and HIV-negative injection-drug users (IDUs) are still needed. To estimate the incidence of pneumonia in a community of former IDUs, we followed 4,236 persons between 1991 and 1994; 1,114 (26.3%) were HIV-positive and 3,122 (73.7%) were HIV-negative. All patients were evaluated for pneumonia by standard criteria, a serum sample was obtained from each participant at least once a year, and laboratory values were monitored. Overall, 149 episodes of pneumonia occurred among HIV-positive patients and 61 among HIV-negative patients; incidence rates were 90.5 and 14.2 (per 1,000 person-years), respectively. The most common etiologic agents were Streptococcus pneumoniae, Chlamydia pneumoniae, and Haemophilus influenzae. Among the HIV-positive former IDUs, there was a 1.37-fold increase in the relative risk of pneumonia for every decrease of 100/mm3 in the CD4 cell count (95% confidence interval, 1.16-1.61). The incidence of community-acquired pneumonia was markedly higher among HIV-positive participants than among HIV-negative ones, a finding similar to that concerning the general population.

AIDS: a major health problem among young Italian women

OBJECTIVE

To estimate the extent of the HIV/AIDS epidemic among Italian women and to assess its impact on mortality. Further, to assess the incidence of AIDS and the main characteristics of women affected by AIDS: with particular attention to those aged 25-34 years, and to identify differences in these characteristics compared with men infected with AIDS.

METHODS

Incidence data were derived from the Italian National Register of AIDS Cases (RAIDS). The most recent complete data refer to cases diagnosed to the end of 1994. Mortality data were collected from the Italian mortality database, which is held by the Italian National Census Bureau (ISTAT) and processed by the Laboratory of Epidemiology and Biostatistics at the National Institute of Health of Italy (Istituto Superiore di Sanitá; ISS). The most recent mortality data refer to 1992, but projections were made to obtain mortality data up to 1994. All the rates were standardized by age and sex.

RESULTS

A total of 26 957 cases of AIDS, 21 441 men (79.5%) and 5516 women (20.5%), diagnosed before the end of 1994 were reported to RAIDS. The majority of cases and deaths occurred in individuals aged 25-34 years. The incidence of AIDS among women increased from 2.1 per 100 000 in 1987 to 17.2 per 100 000 in 1994. The sex ratio (men:women) fell from 5.2 in 1987 to 2.9 in 1994. In 1992, AIDS was the second most common cause of death (slightly behind cancer and ahead of traffic accidents) in Italy, but was the most common cause in three regions of northern Italy (Liguria, Lombardia and Emilia).

CONCLUSIONS

Although the AIDS epidemic in the past has predominantly affected young men, AIDS is now rapidly becoming a major health problem for young women in Italy. Moreover, as these women are at reproductive age, this may have important consequences in terms of increased morbidity and mortality among children.

Temporal trends of initial CD4 cell counts following human immunodeficiency virus seroconversion in Italy, 1985-1992. The Human Immunodeficiency Virus Italian Seroconversion Study

To determine whether initial CD4 cell counts after human immunodeficiency virus (HIV) seroconversion have decreased over calendar time among participants in the Italian Seroconversion Study, HIV seroconverters who between 1985 and 1992 had a documented negative serology followed by a positive serology within 12 months and a first CD4 cell measurement within 24 months of seroconversion (defined as midpoint of negative and positive HIV tests) were cross-tabulated by year of seroconversion. Linear regression methods were used to examine temporal trends in initial CD4 level after adjustment for age, lag time of seroconversion, lag time of CD4 cell measurement, risk group, and clinical center. Between 1985 and 1992, the overall median initial CD4 cell level after seroconversion was 660 microliters with a median lag time of 212 days and 137 days for seroconversion and first CD4 cell measurement, respectively. In univariate and multivariate models, the CD4 cell count increases of 4.3 and 4.2 cells microliters/year, respectively, were not statistically significant. These data do not identify a trend of lower CD4 counts following HIV seroconversion in Italy and suggest indirectly that HIV has probably not become more virulent between 1985 and 1992.

Coinfection of hepatitis C virus with human immunodeficiency virus and progression to AIDS. Italian Seroconversion Study

To assess the influence of hepatitis C virus (HCV) on the natural history of human immunodeficiency virus (HIV) infection, a longitudinal study was conducted among 416 HIV-positive, AIDS-free persons infected through injecting drug use or homosexual or heterosexual activity and with known seroconversion dates. End points were diagnosis of AIDS and a CD4 cell count of < 100 x 10(6) cells/L. HCV antibodies were detected in 214 persons (51.4%). The crude relative hazard (RH) of progression to AIDS was 0.96 (95% confidence interval [CI], 0.53-1.76) for HCV-coinfected participants compared with those not coinfected. After adjustment for CD4 cell count, the RH was 0.97 (95% CI, 0.52-1.79). Similar RHs were found using a CD4 cell count of < 100 x 10(6) cells/L as the end point. The median CD4 cell loss was 4.83 x 10(6) cells/L per month among coinfected persons and 5.70 x 10(6) cells/L per month among the others. These results suggest that coinfection with HCV does not influence clinical and immunologic progression of HIV disease.

The classification of AIDS cases: concordance between two AIDS surveillance systems in Italy

This study assessed the concordance between the transmission classification of 725 acquired immunodeficiency syndrome (AIDS) cases by the Italian AIDS Registry (the national surveillance system) and the classification of the same cases by the Italian Cooperative Group on AIDS-Related Tumors. A high degree of concordance emerged for intravenous drug users in both sexes (kappa = 0.88; 95% confidence interval [CI] = 0.84, 0.92), for homosexual men (kappa = 0.83; 95% CI = 0.79, 0.87), and for persons infected through contaminated blood or blood derivatives (kappa = 1.00). The concordance was lower among heterosexual men (kappa = 0.51; 95% CI = 0.37, 0.65) and especially among men whose risk group was not determined (kappa = 0.28; 95% CI = 0.12, 0.44). The discrepancies observed among heterosexual men indicate a need for continuing and accurate monitoring of AIDS reporting by transmission category.

CD4 lymphocyte count as a determinant of the time from HIV seroconversion to AIDS and death from AIDS: evidence from the Italian Seroconversion Study

OBJECTIVES

It is well established that a low CD4 lymphocyte count is strongly associated with an increased risk of AIDS in HIV infection. We attempted to determine whether the link is sufficiently strong that the wide inter-person variability in times from HIV infection to AIDS can be explained solely by differences in CD4 count experience.

METHODS

We followed 1090 HIV-infected individuals for up to 12.8 years from seroconversion (median, 3.5 years; 25% for more than 5.2 years). The median interval between last negative and first positive anti-HIV tests was 9 months. A median of four CD4 counts per subject were measured.

RESULTS

Individuals with CD4 lymphocyte counts above 250 x 10(6)/l cells experienced an AIDS incidence rate of one per 339 years (0.3 per 100 years; 10 cases in 3394 person-years), compared with one per 6 years in those whose count had declined below this level (17.2 per 100 years; 96 cases in 559 person-years) and one per year in those whose count had declined below 50 x 10(6)/l (100.0 per 100 years; 41 cases in 41 person-years). The AIDS rate increased by an average of 33% [relative rate, 1.33; 95% confidence interval (CI), 1.20-1.49; P = 0.0001] with every year from seroconversion; one per 46 years (2.2 per 100 years) for people seropositive for less than 5 years compared with one per 14 years (7.3 per 100 years) for those seropositive for more than 5 years. After adjusting for the tendency for CD4 lymphocyte counts to be higher soon after seroconversion, the relative rate declined to 1.07 (95% CI, 0.94-1.22) per year from seroconversion (P = 0.32). This result was similar when those infected through sharing injecting equipment, homosexual sex, and other routes were considered separately. The relative rate per year from seroconversion for death due to AIDS fell from 1.41 (P = 0.0001) to 1.00 (P = 0.99) after adjusting for CD4 count.

CONCLUSIONS

Most of the inter-person variability in time from HIV infection to AIDS appears to result from differences in CD4 lymphocyte counts. HIV infection appears to cause AIDS and death largely by its ability to induce CD4 lymphocytopaenia or some closely correlated abnormality.