HIV-induced immunodeficiency and mortality from AIDS-defining and non-AIDS-defining malignancies

Review article: malignancy on thiopurine treatment with special reference to inflammatory bowel disease

BACKGROUND

Immunosuppression is a risk factor for carcinogenesis. Thiopurines specifically contribute to this. As thiopurines are used more aggressively in the treatment of IBD, it is likely that we will see more thiopurine-related malignancy.

AIM

To review the literature, exploring how immunosuppression, thiopurines specifically, might cause cancer and which malignancies occur in practice, placing specific emphasis on IBD cohorts.

METHODS

Search terms included 'malignancy' 'cancer' 'azathioprine' 'mercaptopurine' 'tioguanine (thioguanine)' 'thiopurine' and 'inflammatory bowel disease' 'Crohn's disease' 'ulcerative colitis'. We also searched for specific cancers (lymphoma, colorectal cancer, skin cancer, cervical cancer) and reviewed the reference lists of the articles detected.

RESULTS

Immunosuppression is associated with an increased risk of cancer. Thiopurines are associated with specific additional risks. In IBD cohorts, very few thiopurine-related malignancies have been reported. However, studies suggest a relative risk of 4-5 for lymphoma. This still translates into a low actual risk, (one extra lymphoma in every 300-1400 years of thiopurine treatment).

CONCLUSIONS

Whilst we must be aware of this risk and counsel our patients appropriately, thiopurines remain a mainstay of IBD therapy. We present practical advice aimed at minimizing our patients' risk of developing malignancy, whilst optimizing the benefits that thiopurines can provide.

Randomized trial of a computerized coronary heart disease risk assessment tool in HIV-infected patients receiving combination antiretroviral therapy

BACKGROUND

Exposure to combination antiretroviral therapy (cART) can lead to important metabolic changes and increased risk of coronary heart disease (CHD). Computerized clinical decision support systems have been advocated to improve the management of patients at risk for CHD but it is unclear whether such systems reduce patients' risk for CHD.

METHODS

We conducted a cluster trial within the Swiss HIV Cohort Study (SHCS) of HIV-infected patients, aged 18 years or older, not pregnant and receiving cART for >3 months. We randomized 165 physicians to either guidelines for CHD risk factor management alone or guidelines plus CHD risk profiles. Risk profiles included the Framingham risk score, CHD drug prescriptions and CHD events based on biannual assessments, and were continuously updated by the SHCS data centre and integrated into patient charts by study nurses. Outcome measures were total cholesterol, systolic and diastolic blood pressure and Framingham risk score.

RESULTS

A total of 3,266 patients (80% of those eligible) had a final assessment of the primary outcome at least 12 months after the start of the trial. Mean (95% confidence interval) patient differences where physicians received CHD risk profiles and guidelines, rather than guidelines alone, were total cholesterol -0.02 mmol/l (-0.09-0.06), systolic blood pressure -0.4 mmHg (-1.6-0.8), diastolic blood pressure -0.4 mmHg (-1.5-0.7) and Framingham 10-year risk score -0.2% (-0.5-0.1).

CONCLUSIONS

Systemic computerized routine provision of CHD risk profiles in addition to guidelines does not significantly improve risk factors for CHD in patients on cART.

When to start antiretroviral therapy

The question of when to start combination antiretroviral therapy for treatment-naïve patients has always been controversial. This is particularly true in the current era, with major guidelines recommending very different treatment strategies. Despite a lack of clarity regarding the optimal time to begin therapy, there has been a recent shift toward earlier initiation. This more aggressive approach is driven by several observations. First, effective viral suppression with therapy can prevent non-AIDS-related morbidity and mortality. Second, therapy can prevent irreversible harm to the human immune system. Third, therapy may prevent transmission of HIV to others, and thus have a potential public health benefit. For patients who are motivated and willing to initiate early treatment, the collective benefits of early therapy may outweigh the well-documented risks of antiretroviral medications.

Prospective, randomized, open label trial of Efavirenz vs Lopinavir/Ritonavir in HIV+ treatment-naive subjects with CD4+<200 cell/mm3 in Mexico

OBJECTIVE

To compare the efficacy of efavirenz (EFV) vs lopinavir/ritonavir (LPV/r) in combination with azidothymidine/lamivudine in antiretroviral therapy naive, HIV+ individuals presenting for care with CD4 counts <200/mm.

METHODS

Prospective, randomized, open label, multicenter trial in Mexico. HIV-infected subjects with CD4 <200/mm were randomized to receive open label EFV or LPV/r plus azidothymidine/lamivudine (fixed-dose combination) for 48 weeks. Randomization was stratified by baseline CD4 cell count (< or =100 or >100/mm). The primary endpoint was the percentage of patients with plasma HIV-1 RNA <50 copies/mL at 48 weeks by intention-to-treat analysis.

RESULTS

A total of 189 patients (85% men) were randomized to receive EFV (95) or LPV/r (94). Median baseline CD4 were 64 and 52/mm, respectively (P = not significant). At week 48, by intention-to-treat analysis, 70% of EFV and 53% of LPV/r patients achieved HIV-1 RNA <50 copies/mL [estimated difference 17% (95% confidence interval 3.5 to 31), P = 0.013]. The proportion with HIV-1 RNA <400 copies/mL was 73% with EFV and 65% with LPV/r (P = 0.25). Virologic failure occurred in 7 patients on EFV and 17 on LPV/r. Mean CD4 count increases (cells/mm) were 234 for EFV and 239 for LPV/r. Mean change in total cholesterol and triglyceride levels were 50 and 48 mg/dL in EFV and 63 and 116 mg/dL in LPV/r (P = 0.24 and P < 0.01).

CONCLUSIONS

In these very advanced HIV-infected ARV-naive subjects, EFV-based highly active antiretroviral therapy had superior virologic efficacy than LPV/r-based highly active antiretroviral therapy, with a more favorable lipid profile.

Repertoire development and the control of cytotoxic/effector function in human gammadelta T cells

T cells develop into two major populations distinguished by their T cell receptor (TCR) chains. Cells with the alphabeta TCR generally express CD4 or CD8 lineage markers and mostly fall into helper or cytotoxic/effector subsets. Cells expressing the alternate gammadelta TCR in humans generally do not express lineage markers, do not require MHC for antigen presentation, and recognize nonpeptidic antigens. We are interested in the dominant Vgamma2Vdelta2+ T cell subset in human peripheral blood and the control of effector function in this population. We review the literature on gammadelta T cell generation and repertoire selection, along with recent work on CD56 expression and defining a cytotoxic/effector lineage within the phosphoantigen-reactive Vgamma2Vdelta2 cells. A unique mechanism for MHC-independent repertoire selection is linked to the control of effector function that is vital to the role for gammadelta T cells in tumor surveillance. Better understanding of these mechanisms will improve our ability to exploit this population for tumor immunotherapy.

HIV-induced immune activation: pathogenesis and clinical relevance - summary of a workshop organized by the German AIDS Society (DAIG e.v.) and the ICH Hamburg, Hamburg, Germany, November 22, 2008

This manuscript is communicated by the German AIDS Society (DAIG) http://www.daignet.de. It summarizes a series of presentations and discussions during a workshop on immune activation due to HIV infection. The workshop was held on November 22^nd 2008 in Hamburg, Germany. It was organized by the ICH Hamburg under the auspices of the German AIDS Society (DAIG e.V.).

Unmet therapeutic needs in the new era of combination antiretroviral therapy for HIV-1

Significant advances in outcomes have been achieved with combination antiretroviral therapy (cART) in patients living with HIV. However, several ongoing needs remain with respect to the development of new treatments. The need for new or enhanced cART may become increasingly apparent as patients live longer with HIV and a greater proportion die from non-AIDS-related illnesses. Immunological response to cART is variable and immune failure occurs, despite virological control. Moreover, viral suppression can be incomplete due to insufficient antiviral efficacy, acquired or transmitted drug resistance, suboptimal pharmacokinetics/pharmacodynamics and lack of adherence. Chronic immune activation may continue even when viral replication is relatively restrained. Patients continue to experience cardiovascular and metabolic complications, due to disease, treatment and ageing. In addition, neurocognitive impairment and malignancy are important sources of ongoing morbidity despite cART. HIV also affects immune system senescence and bone turnover. This review discusses potential unmet needs with respect to these issues.

Cohort studies: to what extent can they inform treatment guidelines?

PURPOSE OF REVIEW

This review examines situations in which information from cohort studies has proved to be useful for the development of treatment guidelines.

RECENT FINDINGS

Although there are several reasons why randomized controlled trials (RCTs) are felt to provide the most robust evidence for treatment guidelines, they may suffer from insufficient duration of follow-up, inadequate power to consider differences in important adverse events and highly selected patient populations. Furthermore, as most RCTs are performed for licensing purposes, strategic treatment decisions often lack supportive evidence from RCTs. Although data from cohort studies may be used to complement information from RCTs, cohort studies themselves are susceptible to several biases (most notably confounding) which may limit their findings. However, in the HIV field, information from such studies has been influential in guiding decisions relating to when to start highly active antiretroviral therapy, what drugs to use in the initial highly active antiretroviral therapy regimen and when to switch highly active antiretroviral therapy should virological failure occur.

SUMMARY

Given the biases that may be present, caution should be exercised when interpreting findings from cohort studies, particularly if comparisons are made of treatment strategies that involve some element of patient or clinician choice.

Analysis of serious non-AIDS events among HIV-infected adults at Latin American sites

OBJECTIVE

Acquired immune deficiency appears to be associated with serious non-AIDS (SNA)-defining conditions such as cardiovascular disease, liver and renal insufficiency and non-AIDS-related malignancies. We analysed the incidence of, and factors associated with, several SNA events in the LATINA retrospective cohort.

MATERIALS AND METHODS

Cases of SNA events were recorded among cohort patients. Three controls were selected for each case from cohort members at risk. Conditional logistic models were fitted to estimate the effect of traditional risk factors as well as HIV-associated factors on non-AIDS-defining conditions.

RESULTS

Among 6007 patients in follow-up, 130 had an SNA event (0.86 events/100 person-years of follow-up) and were defined as cases (40 with cardiovascular events, 54 with serious liver failure, 35 with non-AIDS-defining malignancies and two with renal insufficiency). Risk factors such as diabetes, hepatitis B and C virus coinfections and alcohol abuse showed an association with events, as expected. The last recorded CD4 T-cell count prior to index date (P = 0.0056, with an average difference of more than 100 cells/μL) and area under the CD4 cell curve in the year previous to index date (P = 0.0081) were significantly lower in cases than in controls. CD4 cell count at index date was significantly associated with the outcome after adjusting for risk factors.

CONCLUSIONS

The incidence and type of SNA events found in this Latin American cohort are similar to those reported in other regions. We found a significant association between immune deficiency and the risk of SNA events, even in patients under antiretroviral treatment.

The future of antiretroviral therapy: challenges and needs

The introduction of combination antiretroviral therapy (cART) has substantially modified the natural history of HIV infection. At the beginning of the cART era the objective was focused on HIV-1-associated mortality and morbidity, but as this objective was accomplished other issues emerged, including toxicity, resistance and compliance with treatment. Moreover, the participation of other disease mechanisms, such as proinflammatory activity, in the so-called non-AIDS events is becoming increasingly important. To overcome these issues, therapeutic options have dramatically expanded, which has made the management of HIV-1-infected patients increasingly complex. The intense changes seen raise the question of what will be the future of HIV infection and its treatment. A projection into the future may help to reflect on current limitations, needs and research priorities, to optimize patient care. To debate on this topic a group of 38 experts has initiated The HIV 2020 Project, with the aim of reflecting on the future of HIV infection and identifying the needs that should be the attention of research in different areas. This document summarizes the group's conclusions on the future of antiretroviral treatment, presented as 20 relevant questions. Each question includes the current status of the topic and our vision for the future.

Innate immunity and chronic immune activation in HCV/HIV-1 co-infection

Innate immune responses are critical in the defense against viral infections. NK cells, myeloid and plasmacytoid dendritic cells, and invariant CD1d-restricted NKT cells mediate both effector and regulatory functions in this early immune response. In chronic uncontrolled viral infections such as HCV and HIV-1, these essential immune functions are compromised and can become a double edged sword contributing to the immunopathogenesis of viral disease. In particular, recent findings indicate that innate immune responses play a central role in the chronic immune activation which is a primary driver of HIV-1 disease progression. HCV/HIV-1 co-infection is affecting millions of people and is associated with faster viral disease progression. Here, we review the role of innate immunity and chronic immune activation in HCV and HIV-1 infection, and discuss how mechanisms of innate immunity may influence protection as well as immunopathogenesis in the HCV/HIV-1 co-infected human host.

When and why to start antiretroviral therapy?

The question about when to start antiretroviral therapy in HIV-1-infected patients has been debated since the discovery of the first antiretroviral agent (zidovudine) back in 1986 and has been fuelled by the introduction of highly active combined antiretroviral therapy (cART) 10 years later in 1996. The dramatic improvement in the mortality rate associated with cART supported the principle of 'hitting early and hard', but the initial enthusiasm was quickly tempered by the realization of the inconveniences and the short- to mid-term treatment-related toxicities, including lipoatrophy. In 2009, cART can be very simple and generally well tolerated. All patients with a CD4+ T cell count of <350 cells/mm(3) should receive cART. Moreover, several cohort studies have convincingly demonstrated a significant reduction of AIDS- and non-AIDS-related events when cART is initiated at >350 CD4+ T lymphocytes/mm(3), and even at >500 CD4+ T lymphocytes/mm(3). Also, cART may be considered when there are associated co-morbidities, such as hepatitis C. In addition to individual benefits, an undetectable viral load in response to cART is associated with a substantial reduction in the likelihood of HIV transmission. This can benefit seronegative sexual partners and can potentially diminish the number of new infections, especially if those infected persons unaware of their situation can be identified and advised to initiate cART. Willingness to be treated and to adhere to the prescribed medication still remains the key to success.

Association of HIV infection, demographic and cardiovascular risk factors with all-cause mortality in the recent HAART era

OBJECTIVE

To determine the relationship of HIV infection, demographic, and cardiovascular disease (CVD) risk factors with mortality in the recent highly active antiretroviral therapy era.

METHODS

Vital status was ascertained from 2004 to 2007 in 922 HIV infected and 280 controls in the Study of Fat Redistribution and Metabolic Change in HIV infection; 469 HIV infected were included in analysis comparing HIV with similar age controls. Multivariable exponential survival regression (adjusting for demographic and CVD factors) estimated hazard ratios (HRs) for death.

RESULTS

After 5 years of follow-up, the overall adjusted mortality HR was 3.4 [95% confidence interval (CI): 1.35-8.5]; HR was 6.3 among HIV infected with CD4 < 200 (95% CI: 2.2-18.2), 4.3 with CD4 200-350 (95% CI: 1.14-16.0), and 2.3 with CD4 > 350 (95% CI: 0.78-6.9). Among HIV infected, current smoking (HR = 2.73 vs. never smokers, 95% CI: 1.64-4.5) and older age (HR = 1.61 per decade, 95% CI: 1.27-2.1) were independent risk factors for death; higher baseline CD4 count was associated with lower risk (HR = 0.65 per CD4 doubling, 95% CI: 0.58-0.73).

CONCLUSIONS

HIV infection was associated with a 3-fold mortality risk compared with controls after adjustment for demographic and CVD risk factors. In addition to low baseline CD4 count, older age and current smoking were strong and independent predictors of mortality in a US cohort of HIV-infected participants in clinical care.

Role of the CD4 count in HIV management

As a result of successful antiretroviral treatment over the last 20 years, HIV has become more of a chronic disease for practitioners to manage, requiring careful, but routine, clinical monitoring. Laboratory markers, such as the HIV-1 RNA viral load and CD4 cell count, are regularly used for patient management in addition to predicting disease progression and/or treatment outcomes. The HIV viral load is considered to be the gold standard for evaluating treatment success, although it is often limited by the cost. Furthermore, in certain cases, there is a mismatch between an undetectable viral load (<50 copies/ml) and the absence of immune reconstitution, which can be confusing to both the treatment provider and patient. In this review, the utility of the CD4 count as a predictor for HIV disease progression in patients not on therapy is evaluated, as well as a method for monitoring a patient’s response to therapy. Its use in predicting immune reconstitution in patients initiating antiretrovirals is also identified. We hope to aid the clinician by examining the most recent literature and discussing the added value of the CD4 count in the management of a person with HIV infection.

Predicting direct costs of HIV care during the first year of darunavir-based highly active antiretroviral therapy using CD4 cell counts: evidence from POWER

BACKGROUND

Given the association between CD4 cell counts and HIV-related morbidity/mortality, new antiretroviral therapies could potentially lower the direct costs of HIV care by raising CD4 cell counts.

OBJECTIVES

To predict the effects of the ritonavir-boosted, HIV protease inhibitor (PI) darunavir on the direct costs of care, while accounting for CD4 cell counts, during the first year of therapy in highly treatment-experienced, HIV-infected adults in different healthcare settings.

METHODS

The mean annual per-patient cost of darunavir/ritonavir (DRV/r) and control PI-based highly active antiretroviral therapy (HAART) was calculated from the proportional use of antiretroviral agents in the DRV/r and control PI arms of the pooled POWER 1 and 2 trials, applying drug-acquisition costs for five healthcare settings. Non-antiretroviral-related costs by CD4 cell count, derived from non-interventional studies in the same settings, were applied to the POWER data (proportion of patients with CD4 cell counts in different strata at week 48) to estimate mean annual non-antiretroviral-related costs per patient in patients receiving DRV/r or control PI-based HAART during year 1.

RESULTS

Across all settings, the mean annual per-patient cost of DRV/r-based treatment was 2-19% higher than that of control PI-based therapy during the first year of therapy. By raising CD4 cell counts, however, DRV/r-based regimens were predicted to lower mean annual non-antiretroviral-related costs by 16-38% compared with control PI-based therapy. When combined, the total annual per-patient cost of HIV care during the first year of therapy was estimated to be 7% lower in the DRV/r compared with the control PI arm using US data, 8% lower using Swedish data, budget neutral using UK and Belgian data and 5% higher using Italian data.

CONCLUSIONS

Darunavir-based HAART may lower non-antiretroviral-related costs compared with control PI-based therapy in highly treatment-experienced, HIV-infected patients during the first year of therapy by improving patients' CD4 cell counts. These costs could partly/fully offset the increased acquisition cost of DRV/r in this patient population over the same period.

The cost of managing HIV infection in highly treatment-experienced, HIV-infected adults in France

BACKGROUND

Highly active antiretroviral therapy (HAART) has greatly enhanced HIV management, lowering the risk of clinical disease progression and death by substantially improving HIV-induced immune deficiency. Lower CD4 cell counts have consistently been associated with higher direct costs of HIV patient care. The aim of this study was to analyze HIV costs of care in France at different levels of HIV-induced immune deficiency (as measured by the CD4 cell count) using recent data from treatment-experienced patients.

METHODS

This analysis used data from the French Hospital Database in HIV, containing data on approximately 50% of the French HIV population. Patients were included in the analysis if they had visited a participating centre from 2003 to 2005, had CD4 cell counts determined at least twice during the study period, and had been prescribed at least two nucleoside reverse transcriptase inhibitors, one non-nucleoside reverse transcriptase inhibitor and two protease inhibitors since their first consultation. Resources consumed were counted and aggregated according to the CD4 cell count level. Standard costs were applied.

RESULTS

Periods with the lowest CD4 cell counts were associated with increased prescription rates of antiviral agents (other than anti-HIV agents), antiparasitic drugs and antimycobacterial agents. Antiretroviral treatments accounted for 80% of all medications prescribed during the study period. Hospitalization rates decreased with increasing CD4 cell counts, with 0.72 hospitalizations per patient-year for those with CD4 cell counts of 50 cells/mm³ or less compared with 0.05 per patient-year for patients with CD4 cell counts greater than 500 cells/mm³. There was a clear trend towards lower mean healthcare costs per patient-year with decreasing immune deficiency; from €34,286 to €12,361.

CONCLUSIONS

Our study showed an association between the degree of HIV-induced immune deficiency (measured by CD4 cell count) and the costs of managing HIV infection among highly pre-treated, HIV-infected individuals in France in the HAART era.

Characteristics of non-Hodgkin lymphoma arising in HIV-infected patients with suppressed HIV replication

OBJECTIVE

Despite effective treatment of HIV infection, some patients still develop non-Hodgkin lymphoma (NHL). We analysed patients with HIV-associated NHL and undetectable plasma HIV-RNA, according to the duration of HIV suppression.

METHODS

Out of 388 patients included in a prospective cohort of HIV-associated NHL from 1996 to 2008, 128 (33%) had a plasma HIV-RNA below 500 copies/ml and were included in the study. Patients with long-term HIV suppression (>18 months) were compared with patients with recent HIV suppression (< or = 18 months).

RESULTS

All patients but three were treated with combination antiretroviral therapy, with a median duration of 2.2 years. The median duration of HIV suppression was 10.1 months. Most cases (65%) occurred within 18 months following HIV suppression. In the more than 18 months group, patients developed NHL at a higher CD4 cell count than patients with 18 months or less of HIV suppression (359 versus 270 cells/microl, P = 0.02). None of the NHL characteristics were different between the two groups. Outcome was similar in the two groups (complete remission, 64 versus 72.5%; P = 0.35 and 3-year survival, 46 versus 56%; P = 0.08). In addition, 52% of the tumours were Epstein-Barr virus or human herpesvirus 8 associated, without any difference in the proportion of virus-associated tumours according to the duration of HIV suppression.

CONCLUSION

In patients with undetectable HIV-RNA, NHL occurred mainly within the first 18 months following HIV suppression. In patients developing NHL after long-term HIV suppression, the level of CD4 cell count was higher, but the association with Epstein-Barr virus or human herpesvirus 8 and the prognosis were similar to that observed in patients with recent HIV suppression.

AIDS-related and non-AIDS-related mortality in the Asia-Pacific region in the era of combination antiretroviral treatment

OBJECTIVE

Although studies have shown reductions in mortality from AIDS after the introduction of combination antiretroviral treatment (cART), little is known about cause-specific mortality in low-income settings in the cART era. We explored predictors of AIDS and non-AIDS mortality and compared cause-specific mortality across high-income and low-income settings in the Asia-Pacific region.

METHODS

We followed patients in the Asia Pacific HIV Observational Database from the date they started cART (or cohort enrolment if cART initiation was identified retrospectively), until the date of death or last follow-up visit. Competing risks methods were used to estimate the cumulative incidence, and to investigate predictors, of AIDS and non-AIDS mortality.

RESULTS

Of 4252 patients, 215 died; 89 from AIDS, 97 from non-AIDS causes and 29 from unknown causes. Age more than 50 years [hazard ratio 4.29; 95% confidence interval (CI) 2.10-8.79] and CD4 cell counts less than or equal to 100 cells/microl (hazard ratio 8.59; 95% CI 5.66-13.03) were associated with an increased risk of non-AIDS mortality. Risk factors for AIDS mortality included CD4 cell counts less than or equal to 100 cells/microl (hazard ratio 34.97; 95% CI 18.01-67.90) and HIV RNA 10 001 or more (hazard ratio 4.21; 95% CI 2.07-8.55). There was some indication of a lower risk of non-AIDS mortality in Asian high-income, and possibly low-income, countries compared to Australia.

CONCLUSION

Immune deficiency is associated with an increased risk of AIDS and non-AIDS mortality. Older age predicts non-AIDS mortality in the cART era. Less conclusive was the association between country-income level and cause-specific mortality because of the relatively high proportion of unknown causes of death in low-income settings.

High levels of chronic immune activation in the T-cell compartments of patients coinfected with hepatitis C virus and human immunodeficiency virus type 1 and on highly active antiretroviral therapy are reverted by alpha interferon and ribavirin treatment

Chronic immune activation is a driver of human immunodeficiency virus type 1 (HIV-1) disease progression. Here, we describe that subjects with chronic hepatitis C virus (HCV)/HIV-1 coinfection display sharply elevated immune activation as determined by CD38 expression in T cells. This occurs, despite effective antiretroviral therapy, in both CD8 and CD4 T cells and is more pronounced than in the appropriate monoinfected control groups. Interestingly, the suppression of HCV by pegylated alpha interferon and ribavirin treatment reduces activation. High HCV loads and elevated levels of chronic immune activation may contribute to the high rates of viral disease progression observed in HCV/HIV-1-coinfected patients.

Effect of immunodeficiency, HIV viral load, and antiretroviral therapy on the risk of individual malignancies (FHDH-ANRS CO4): a prospective cohort study

BACKGROUND

The relative roles of immunodeficiency, HIV viral load, and combination antiretroviral therapy (cART) in the onset of individual cancers have rarely been examined. We examined the effect of these factors on the risk of specific cancers in patients infected with HIV-1.

METHODS

We investigated the incidence of both AIDS-defining cancers (Kaposi's sarcoma, non-Hodgkin lymphoma, and cervical cancer) and non-AIDS-defining cancers (Hodgkin's lymphoma, lung cancer, liver cancer, and anal cancer) in 52 278 patients followed up in the French Hospital Database on HIV cohort during 1998-2006 (median follow-up 4.9 years, IQR 2.1-7.9; 255 353 person-years). We tested 78 models with different classifications of immunodeficiency, viral load, and cART with Poisson regression.

FINDINGS

Current CD4 cell count was the most predictive risk factor for all malignancies apart from anal cancer. Compared with patients with CD4 count greater than 500 cells per microL, rate ratios (RR) ranged from 1.9 (95% CI 1.3-2.7) for CD4 counts 350-499 cells per microL to 25.2 (17.1-37.0) for counts less than 50 cells per microL for Kaposi's sarcoma (p<0.0001), from 1.3 (0.9-2.0) to 14.8 (9.7-22.6) for non-Hodgkin lymphoma (p<0.0001), from 1.2 (0.7-2.2) to 5.4 (2.4-12.1) for Hodgkin's lymphoma (p<0.0001), from 2.2 (1.3-3.6) to 8.5 (4.3-16.7) for lung cancer (p<0.0001), and from 2.0 (0.9-4.5) to 7.6 (2.7-20.8) for liver cancer (p<0.0001). For cervical cancer, we noted a strong effect of current CD4 (RR 0.7 per log(2), 95% CI 0.6-0.8; p=0.0002). The risk of Kaposi's sarcoma and non-Hodgkin lymphoma increased for current plasma HIV RNA greater than 100 000 copies per mL compared with patients with controlled viral load (RR 3.1, 95% CI 2.3-4.2, p<0.0001; and 2.9, 2.1-3.9, p<0.0001, respectively), whereas cART was independently associated with a decreased incidence (0.3, 0.2-0.4, p<0.0001; and 0.8, 0.6-1.0, p=0.07, respectively). The RR of cervical cancer for those receiving cART was 0.5 (0.3-0.9; p=0.03). The risk of anal cancer increased with the time during which the CD4 count was less than 200 cells per microL (1.3 per year, 1.2-1.5; p=0.0001), and viral load was greater than 100 000 copies per mL (1.2 per year, 1.1-1.4, p=0.005).

INTERPRETATION

cART would be most beneficial if it restores or maintains CD4 count above 500 cells per microL, thereby indicating an earlier diagnosis of HIV infection and an earlier treatment initiation. Cancer-specific screening programmes need to be assessed in patients with HIV.

FUNDING

Agence Nationale de Recherches sur le SIDA et les hépatites (ANRS), INSERM, and the French Ministry of Health.

Adult mortality and antiretroviral treatment roll-out in rural KwaZulu-Natal, South Africa

OBJECTIVE

To investigate trends in adult mortality in a population serviced by a public-sector antiretroviral therapy (ART) programme in rural South Africa using a demographic surveillance system.

METHODS

Verbal autopsies were conducted for all 7930 deaths observed between January 2000 and December 2006 in a demographic surveillance population of 74,500 in the Umkhanyakude district of northern KwaZulu-Natal province, South Africa. Age-standardized mortality rate ratios (SMRRs) were calculated for adults aged 25 to 49 years, the group most affected by HIV, for the 2 years before 2004 and the 3 subsequent years, during which ART had been available.

FINDINGS

Between 2002-2003 (the period before ART) and 2004-2006 (the period after ART), HIV-related age-standardized mortality declined significantly, from 22.52 to 17.58 per 1000 person-years in women 25-49 years of age (P < 0.001; SMRR: 0.780; 95% confidence interval, CI: 0.691-0.881), and from 26.46 to 18.68 per 1000 person-years in men 25-49 years of age (P < 0.001; SMRR: 0.706; 95% CI: 0.615-0.811). On sensitivity analysis the results were robust to the possible effect of misclassification of HIV-related deaths.

CONCLUSION

Overall population mortality and HIV-related adult mortality declined significantly following ART roll-out in a community with a high prevalence of HIV infection. A clear public health message of the benefits of treatment, as revealed by these findings, should be part of a multi-faceted strategy to encourage people to find out their HIV serostatus and seek care.

Human immunodeficiency virus in an aging population, a complication of success

The proportion of human immunodeficiency virus (HIV)-infected patients aged 50 and older has greatly increased since the beginning of the epidemic, particularly since 1996, when combination antiretroviral therapy became available. By 2015, 50% of HIV-infected individuals in the United States are likely to be aged 50 and older. The rate of progression of untreated HIV disease, response to therapy, and complicating effects of comorbidities differ in older and younger patients. Older untreated patients with HIV demonstrate faster rates of CD4(+) cell loss and more rapid progression to acquired immunodeficiency syndrome (AIDS) and death than younger individuals. Synergistic deleterious effects of chronic immune activation on the course of HIV infection with the immune senescence of aging may promote this accelerated course. Despite the increasing prevalence in older patients and cost-effectiveness analyses that favor HIV testing, older patients are less likely to be routinely evaluated for HIV infection. Consequently, when diagnosed, older patients have more-advanced disease than do younger patients and, upon presentation with AIDS-defining conditions, are less likely to receive timely appropriate therapy. The treatment of older HIV-infected patients is complicated by preexisting comorbid conditions, including cardiovascular, hepatic, and metabolic complications, which in turn may be exacerbated by the effects of HIV infection per se, modest immunodeficiency (i.e., at CD4(+) counts >350 cells/microL), and the metabolic and other adverse effects of combination antiretroviral therapy. Nevertheless, older patients derive substantial benefit from combination antiretroviral therapy despite having less of an immunological response than expected given their adherence to therapy and excellent virological responses.

Inhibition of envelope-mediated CD4+-T-cell depletion by human immunodeficiency virus attachment inhibitors

Human immunodeficiency virus type 1 (HIV-1) envelope (Env) binding induces proapoptotic signals in CD4(+) T cells without a requirement of infection. Defective virus particles, which represent the majority of HIV-1, usually contain a functional Env and therefore represent a potentially significant cause of such CD4(+)-T-cell loss. We reasoned that an HIV-1 inhibitor that prohibits Env-host cell interactions could block the destructive effects of defective particles. HIV-1 attachment inhibitors (AIs), which potently inhibit Env-CD4 binding and subsequent downstream effects of Env, display low-nanomolar antiapoptotic potency and prevent CD4(+)-T-cell depletion from mixed lymphocyte cultures, also with low-nanomolar potency. Specific Env amino acid changes that confer resistance to AI antientry activity eliminate AI antiapoptotic effects. We observed that CD4(+)-T-cell destruction is specific for CXCR4-utilizing HIV-1 strains and that the fusion blocker enfuvirtide inhibits Env-mediated CD4(+)-T-cell killing but is substantially less potent than AIs. These observations, in conjunction with observed antiapoptotic activities of soluble CD4 and the CXCR4 blocker AMD3100, suggest that this AI activity functions through a mechanism common to AI antientry activity, e.g., prevention of Env conformation changes necessary for specific interactions with cellular factors that facilitate viral entry. Our study suggests that AIs, in addition to having potent antientry activity, could contribute to immune system homeostasis in individuals infected with HIV-1 that can engage CXCR4, thereby mitigating the increased risk of adverse clinical events observed in such individuals on current antiretroviral regimens.

Non-AIDS-defining deaths and immunodeficiency in the era of combination antiretroviral therapy

OBJECTIVE

To assess whether immunodeficiency is associated with the most frequent non-AIDS-defining causes of death in the era of combination antiretroviral therapy (cART).

DESIGN

Observational multicentre cohorts.

METHODS

Twenty-three cohorts of adults with estimated dates of human immunodeficiency virus (HIV) seroconversion were considered. Patients were seroconverters followed within the cART era. Measurements were latest CD4, nadir CD4 and time spent with CD4 cell count less than 350 cells/microl. Outcomes were specific causes of death using a standardized classification.

RESULTS

Among 9858 patients (71 230 person-years follow-up), 597 died, 333 (55.7%) from non-AIDS-defining causes. Non-AIDS-defining infection, liver disease, non-AIDS-defining malignancy and cardiovascular disease accounted for 53% of non-AIDS deaths. For each 100 cells/microl increment in the latest CD4 cell count, we found a 64% (95% confidence interval 58-69%) reduction in risk of death from AIDS-defining causes and significant reductions in death from non-AIDS infections (32, 18-44%), end-stage liver disease (33, 18-46%) and non-AIDS malignancies (34, 21-45%). Non-AIDS-defining causes of death were also associated with nadir CD4 while being cART-naive or duration of exposure to immunosuppression. No relationship between risk of death from cardiovascular disease and CD4 cell count was found though there was a raised risk associated with elevated HIV RNA.

CONCLUSION

In the cART era, the most frequent non-AIDS-defining causes of death are associated with immunodeficiency, only cardiovascular disease was associated with high viral replication. Avoiding profound and mild immunodeficiency, through earlier initiation of cART, may impact on morbidity and mortality of HIV-infected patients.

Temporal changes in causes of death among HIV-infected patients in the HAART era in Rio de Janeiro, Brazil

BACKGROUND

The widespread use of highly active antiretroviral therapy (HAART) has led to marked decreases in death rates in Brazil in HIV-infected individuals. Nonetheless, there are scarce data on specific causes of death.

METHODS

Death rates from a cohort of HIV-infected patients in Rio de Janeiro, Brazil, were analyzed in 2-year periods, from 1997 to 2006. Poisson models and survival models accounting for competing risks were used to assess association of covariables. A standardized validated algorithm was used to ascertain specific causes of death.

RESULTS

Of the 1538 eligible patients, 226 (14.7%) died during the study period, corresponding to a mortality rate of 3.2 per 100 person-years. The median follow-up time was 4.61 years (interquartile range = 5.63 years) and the loss to follow-up rate was 2.4 per 100 person-years. Overall, 98 (43.4%) were classified as non-AIDS-related causes. Although opportunistic infections were the leading causes of death (37.6%), deaths due to AIDS-related causes declined significantly over time (P < 0.01). In the most recent period (2005-2006), the rate of non-AIDS-related causes of deaths was higher than that of AIDS-related causes of death.

CONCLUSIONS

In the HAART era, there has been a significant change in causes of death among HIV-infected patients in Rio de Janeiro. As access to HAART improves, integration with other public programs will become critically important for the long-term success of HIV/AIDS programs in developing countries.

Early antiretroviral therapy: the role of cohorts

PURPOSE OF REVIEW

To review the data that contribute to the debate on the optimal time to initiate highly active antiretroviral therapy in HIV-infected individuals, with a focus on the information that is available from cohort studies.

RECENT FINDINGS

The findings from cohort studies generally support initiation of highly active antiretroviral therapy at CD4 cell counts more than 350 cells/microl. In particular, the findings that death rates among treated HIV-infected individuals are higher than those in the general population, and that the risks of AIDS and serious non-AIDS events are higher in those with lower CD4 cell counts (even when the count remains >350 cells/microl), suggest that earlier initiation of highly active antiretroviral therapy may prevent some excess morbidity and mortality. However, given the lack of adjustment for lead-time bias in many analyses, the potential for residual confounding and the possible incomplete ascertainment of relevant outcomes in cohorts, it cannot be concluded that the benefits of highly active antiretroviral therapy when started at higher CD4 cell counts will outweigh the possible detrimental effects.

SUMMARY

Whereas the data from cohort studies currently support initiation of highly active antiretroviral therapy at CD4 cell counts more than 350 cells/microl, there is an urgent need for data from randomized trials to inform this decision.

Rapidly ageing HIV epidemic among men who have sex with men in Australia

BACKGROUND

Antiretroviral therapy has increased survival for individuals living with HIV and has led to an ageing of this population in developed countries. To date the rate of ageing has been unquantified, giving rise to uncertainty in the treatment emphasis and burden in this population.

METHODS

A mathematical model was used in conjunction with HIV/AIDS data from the Australian National HIV/AIDS Registry to estimate numbers and ages of Australian men who have sex with men (MSM) living with HIV infection from 1980 to 2005.

RESULTS

The average age of HIV-infected Australian MSM is estimated to exceed 44 years of age by the year 2010 and has increased by 1 year of age for each two calendar years since the mid-1980s. HIV-infected MSM over 60 years of age have been increasing in number by 12% per year since 1995. A consequence of successful therapy with subsequent ageing of those infected has meant that from 2001 estimated deaths from other causes exceed AIDS deaths in Australia.

CONCLUSIONS

In summary, our analyses indicate an increasing and rapidly ageing population living with HIV in Australia. This will inevitably lead to more serious non-AIDS conditions in ageing patients living with HIV, and to increased treatment complexity.

Should HIV therapy be started at a CD4 cell count above 350 cells/microl in asymptomatic HIV-1-infected patients?

PURPOSE OF REVIEW

The aim is to review the available data that contribute to the debate on the optimal time to initiate highly active antiretroviral therapy (HAART) in HIV-infected individuals with a CD4 cell count more than 350 cells/microl.

RECENT FINDINGS

Although few randomized data exist that can contribute to this debate, a number of findings from observational studies generally support earlier initiation of HAART. In particular, the findings that death rates remain higher in HIV-infected individuals than in uninfected individuals, even when successfully treated, and that both AIDS and several serious non-AIDS events are more common in those with a lower CD4 cell count (even when this count is above 350 cells/microl), suggest that earlier initiation of HAART may prevent much of the excess morbidity and mortality that remains in this patient group.

SUMMARY

Currently, the data would generally support initiation of HAART in patients with CD4 cell counts more than 350 cells/microl. However, given the strong potential for confounding in observational studies and the lack of adjustment for lead-time bias in many analyses, it is not possible to rule out possible long-term detrimental effects of earlier use of HAART until the results from fully powered randomized trials that directly address this issue become available.

Trends in HIV/TB coinfection in Trinidad and Tobago for the period 1998-2007

OBJECTIVES

The aim of this study was to extend the description of the epidemiologic pattern of human immunodeficiency virus (HIV)/tuberculosis (TB) coinfection from 1998 to 2007 in a high HIV/AIDS prevalence country.

DESIGN AND METHODS

This study utilized registry data to determine yearly TB incidence and HIV coinfection. Mortality rates for coinfected patients were calculated and compared with patients receiving highly active antiretroviral therapy (HAART).

RESULTS

From a TB population of 2010 registered patients, data was collected on the 466 patients with HIV/TB coinfection. The coinfection rate was found to be 23.6% for the study period. Patients on HAART were twice as likely to survive.

DISCUSSION AND CONCLUSIONS

The incidence of TB and HIV/TB coinfection rates continues to be major challenges in the developing world. Demographic, socioeconomic trends as well as risk factors remain unchanged. Increased HIV screening and HAART coverage offers hope for the future.