Mortality before and after HIV infection in the complete UK population of haemophiliacs. UK Haemophilia Centre Directors' Organisation

Systems vaccinology studies - achievements and future potential

Human immune responses to vaccination are variable both within and between populations. Systems vaccinology, which is the application of multi-omics technologies to vaccine studies, seeks to understand such variation and predict responses to optimise vaccine strategies. Here, we outline new approaches to systems vaccinology, focusing on the incorporation of additional cohorts, endpoints and technologies.

All-cause mortality and causes of death in persons with haemophilia: A systematic review and meta-analysis

INTRODUCTION

Improvements in haemophilia treatment over the last decades resulted in increased life expectancy in persons with haemophilia (PWH).

AIM

We conducted a systematic review and meta-analysis to examine all-cause mortality and causes of death among PWH.

METHODS

We systematically searched EMBASE, MEDLINE, Web of Science, CINAHL and Cochrane central register of controlled trials from inception through March 15, 2021. Studies that reported a mortality estimate of PWH compared with the general population and/or reported causes of death were included. Random-effects meta-analysis with inverse variance method was used to obtain pooled estimates. We stratified the analysis by the year of cohort entry (before 2000 vs after 2000).

RESULT

Of the 4769 studies identified, 52 met the eligibility criteria. The pooled all-cause standardized mortality ratio (SMR) from 9 studies in PWH was 1.93 (95% CI 1.38-2.70; I² = 97%). The pooled SMRs before and after the year 2000 were 2.40 (95% CI 1.92-3.00; I² = 87%) and 1.20 (95% CI 1.03-1.40; I² = 62%), respectively. Before the year 2000, 31.2% deaths occurred due to HIV followed by haemorrhage (26.0%), cardiovascular disease (18.2%), liver disease (9.0%), and cancer (8.9%). Fewer (13.9%) deaths were attributable to HIV after the year 2000 with the proportion of deaths due to haemorrhage remaining unchanged.

CONCLUSION

With treatment advances, mortality in PWH has declined over the last few decades approaching that of the general population. However, haemorrhage remains a leading cause of death requiring further attention.

History of the West of Scotland Haemophilia Centre, Glasgow, 1950-2019

Over 70 years, the West of Scotland Haemophilia Centre in the UK has played a leading role in research, education and training. Its staff studied the natural history of haemophilias, their complications, and their treatment complications, pioneered the use of fibrinolytic inhibitors to reduce the risk of receiving a blood transfusion and developed national audit. Collaborations across Scotland with other haemophilia centres and the Scottish National Blood Transfusion Service progressed self-suffi ciency in NHS-produced factor concentrates, heat treatments to prevent HIV and hepatitis transmission, and finally, replacement of human by recombinant factor concentrates.

Why stay? Resilience in haemophilia physicians in the 1980s

AIMS

The occurrence of AIDS in 1980s posed difficult problems for haemophilia clinicians worldwide. The impact of these events is substantial, and the events continue to be subject to judicial proceedings and publications. The stance of haemophilia physicians, particularly their professional resilience, is of importance and remains unexamined.

METHODS

Deploying oral histories informed by literature review of scientific publications and past inquiry reports, this qualitative study addresses how physicians continued to work in haemophilia during those years and attributes that contributed to their resilience.

RESULTS AND CONCLUSIONS

Experience and role in laboratory aspects were of value in handling and communicating uncertainty. Collegiality, peer support and scholarship were important in sustaining their roles, in clinical decision-making and re-instating confidence in the therapeutic relationship during the toughest years of their practice.

Feasibility and Results of a Mobile Haemophilia Outpatient Care Pilot Project

Introduction Regular visits at haemophilia treatment centres (HTCs) in rural regions are often dependent on the access to a private car due to lack of or limited availability of public means. Therefore, a mobile haemophilia outpatient care (MHOC) concept providing home visits to haemophilia patients has been developed by the Saarland HTC, which is located in a rural German region.

Methods Haemophilia patients and their parents were home visited at least twice (baseline, follow-up) by trained medical staff. Socio-demographic and clinical data were collected and interviews were performed asking the patients and parents about their needs and expectations towards such a MHOC.

Results Seventy-nine patients were enrolled (56 adults, 23 children), 62.0% severely affected, 48.1% on prophylaxis, with a mean age of 37.4 ± 16.4 years (17–78) and 9.8 ± 4.2 years (3–16), respectively. Median travel distance to the HTC was 43.5 km (3–200). Note that 92.4% considered an intense binding to the HTC and a MHOC concept as ‘rather/very important’ (88.6%). They expected from a MHOC to provide consulting and educating activities, support in elderhood issues and treatment. For 35.4%, a MHOC could currently provide additional support, mainly due to patient's immobility and need of consultancy. They mainly used services in terms of consultancy in social–legal affairs and support in contacting authorities.

Conclusion The results of this study support the hypothesis that a MHOC concept is a needful supplement in haemophilia comprehensive care and will improve the challenging haemophilia treatment, especially for those with limited access to HTCs or with disabilities.

Haemophilia B: impact on patients and economic burden of disease

Worldwide, haemophilia is the most common hereditary bleeding disorder. The incidence of haemophilia B, however, is considerably less than haemophilia A and consequently appears to have received less attention in the research literature. This article aims to summarise the available evidence documenting the patient and economic burden associated with haemophilia B and current methods of disease management. Both the immediate and long-term clinical consequences of haemophilia B can have significant implications for patients in terms of functional limitations and diminished health-related quality of life (HRQOL). Evidence demonstrates that primary prophylaxis is the optimal strategy for replacing missing clotting factor IX (FIX) and managing haemophilia B. Use of recombinant FIX (rFIX) over plasma-derived FIX (pd-FIX) is also generally preferred for safety reasons. Prophylaxis using currently available rFIX products, however, requires a demanding regimen of intravenous infusions 2–3 times a week which may have significant implications for adherence and ultimately the long-term efficacy of such regimens. Only limited assessments of the cost-effectiveness of prophylactic versus on-demand FIX treatment regimens have been conducted to date. Prophylaxis, however, is generally more costly as greater quantities of FIX are consumed. Any reduction in FIX replacement dosing frequency is expected to improve patient adherence and contribute to improved clinical outcomes, further supporting the costeffectiveness of such interventions. Although a rare disease, as economic constraints for healthcare increase, generating further information regarding the key clinical, patient and economic outcomes associated with haemophilia B will be essential for supporting improvements in care for people with haemophilia B.

The Natural History of Hepatitis C Virus Infection in Hemophiliacs

Hepatitis C virus (HCV) infection is an important cause of morbidity and mortality in patients affected by hereditary bleeding disorders and treated with non-virus inactivated clotting factor concentrates during the 1970s. Since the onset of the infection is known (first treatment with large-pool non-virus inactivated blood products) these patients are a unique model for studying the natural history of HCV infection and associated complications. The course of Hepatitis can be accurately assessed in these patients because they are regularly followed at hemophilia centers with laboratory, clinical and instrumental tests. In this review, we briefly report the present knowledge about the natural course of HCV infection in hemophiliacs, by analyzing the prevalence of HCV infection, the genotype distribution and the risk factors involved in the progression of chronic Hepatitis into severe liver disease as cirrhosis, liver decompensation and hepatocellular carcinoma. Understanding the natural evolution of HCV infection in hemophiliacs helps us to understand better the natural history of HCV infection and to improve the treatment approach to all HCV infected patients.

Is the cardiovascular toxicity of NSAIDS and COX-2 selective inhibitors underestimated in patients with haemophilia?

Joint pain secondary to chronic arthropathy represents one of the most common and debilitating complications of haemophilia, often requiring analgesic care. When compared with nonselective non-steroidal anti-inflammatory drugs (ns-NSAIDs), selective COX-2 inhibitors (coxibs) offer the major advantage of not increasing the bleeding risk, thus being a better choice of analgesics for haemophilia patients. However, several studies have highlighted the cardiovascular risks posed by coxibs and NSAIDs. Given the assumed protection against thrombosis conferred by the deficiency in coagulation factors VIII or IX, these precautions regarding the use of coxibs and NSAIDs have never really been taken into account in haemophilia management. However, contrary to what has long been suspected, haemophilia patients are indeed affected by the same cardiovascular risk factors as nonhaemophiliac patients. Further studies should be conducted to evaluate the impact of NSAIDs on cardiovascular risks and the prevalence of hypertension in haemophilia patients.

How does the humoral response to HIV-2 infection differ from HIV-1 and can this explain the distinct natural history of infection with these two human retroviruses?

A substantial proportion of people infected with HIV-2, the second causative agent of acquired immune deficiency syndrome (AIDS), behave as long-term non-progressors (LTNP) and are able to control the infection more effectively than most HIV-1-infected patients. A better understanding of the differences in the natural history of HIV-1 and HIV-2 infection, and how these relate to the relative immunogenicity and evolution of the two virus strains, could provide important insights into the mechanisms of protective immunity in HIV infection. One of the most striking differences is that most people infected with HIV-2 generate high titers of broadly neutralizing antibodies, whereas this is relatively uncommon in HIV-1 infection. In this review we compare the underlying structural differences of the envelope (Env) between HIV-1 and HIV-2, and examine how these might affect the antibody responses as well as their impact on Env evolution and control of viral replication.

The conundrum of causality in tumor virology: the cases of KSHV and MCV

Controversy has plagued tumor virology since the first tumor viruses were described over 100 years ago. Methods to establish cancer causation, such as Koch's postulates, work poorly or not at all for these viruses. Kaposi's sarcoma herpesvirus (KSHV/HHV8) and Merkel cell polyomavirus (MCV) were both found using nucleic acid identification methods but they represent opposite poles in the patterns for tumor virus epidemiology. KSHV is uncommon and has specific risk factors that contribute to infection and subsequent cancers. MCV and Merkel cell carcinoma (MCC), in contrast, is an example in which mutations to our normal viral flora contribute to cancer. Given the near-ubiquity of human MCV infection, establishing cancer causality relies on molecular evidence that does not fit comfortably within traditional infectious disease epidemiological models. These two viruses reveal some of the challenges and opportunities for inferring viral cancer causation in the age of molecular biology.

AIDS denialism and public health practice

In this paper, we respond to AIDS denialist arguments that HIV does not cause AIDS, that antiretroviral drugs are not useful, and that there is no evidence of large-scale deaths from AIDS, and discuss the key implications of the relationship between AIDS denialism and public health practice. We provide a brief history of how the cause of AIDS was investigated, of how HIV fulfills Koch's postulates and Sir Bradford Hil's criteria for causation, and of the inconsistencies in alternatives offered by denialists. We highlight clinical trials as the standard for assessing efficacy of drugs, rather than anecdotal cases or discussions of mechanism of action, and show the unanimous data demonstrating antiretroviral drug efficacy. We then show how statistics on mortality and indices such as crude death rate, life expectancy, child mortality, and population growth are consistent with the high mortality from AIDS, and expose the weakness of statistics from death notification, quoted by denialists. Last we emphasize that when denialism influences public health practice as in South Africa, the consequences are disastrous. We argue for accountability for the loss of hundreds of thousands of lives, the need to reform public health practice to include standards and accountability, and the particular need for honesty and peer review in situations that impact public health policy.

Mild hemophilia A

Mild hemophilia A (HA), defined by clinical features and factor VIII coagulant activity (FVIII:C) between 0.05 and 0.40 IU mL(-1), is characteristically distinct from severe HA. Indeed, although the molecular characterization of mild HA has permitted the identification of specific underlying mutations, its clinical phenotype is strikingly different from that of patients with a severe FVIII defect, where spontaneous hemorrhages or recurrent joint bleeding are usual manifestations. With aging, mild HA patients may develop complications (i.e. cancers and cardiovascular disorders), the management of which may prove challenging due to the concomitant bleeding tendency. Furthermore, the development of inhibitors provides an additional major complication in these patients, because it increases the severity of the bleeding phenotype and complicates their management. Standard management of mild HA includes the use of desmopressin and antifibrinolytic agents for minor bleeding episodes or surgical procedures, whilst major bleeding or surgery requires replacement therapy with FVIII concentrates. As regards treatment of patients with inhibitors, bypassing agents (i.e. activated prothrombin complex concentrates and recombinant activated FVII) have proven effective in the treatment of bleeding episodes, but as there are insufficient data to determine the optimal approach to immune tolerance induction in this group of patients, their optimal management remains controversial. Rituximab is a newer, promising therapeutic option for inhibitor eradication in such patients. Many aspects concerning mild HA remain to be clarified, including the molecular basis, the natural history and the optimal diagnostic and therapeutic strategies. Only large prospective studies will shed light on this condition.

Survival in a cohort of patients with haemophilia at the haemophilia care center in Vienna, Austria, from 1983 to 2006

Survival of patients with haemophilia is still a relevant issue of great interest. A survival analysis was conducted among 226 patients with haemophilia A and B (128 severe haemophiliacs), who were treated at the haemophilia care centre in Vienna. Information on mortality in our patient cohort was obtained from the Austrian Central Death Register. Overall, 96 of a total of 226 patients (42.5%) died between 1983 and 2006; 37 patients (38.5%) died due to HIV-infection, 15 due to HCV infection, 15 due to bleeding (15.6%, respectively) and 29 (30.2%) due to various other causes. The mortality of HIV-positive patients was 74.3% (n = 55) and that of HCV-positive patients was 40.4% (n = 55) in the analysed period. The patient mortality rates were compared with those of the general Austrian male population following adjustment for age and calendar period. We found that the cumulative relative survival of all patients was 0.694 (95% CI 0.614-0.767). The cumulative relative survival of patients with severe haemophilia (FVIII or IX level < or =1%) was 0.489 (0.394-0.579), but was normal (0.986; 95% CI 0.858-1.082) for patients with mild or moderate haemophilia (FVIII or IX level 2-50%). The survival rate was lowest in HIV-positive patients (0.287; 95% CI 0.186-0.398), but was also decreased to 0.874 (0.776-0.951) in HIV-negative patients. It can, therefore, be concluded that the survival of patients with severe haemophilia is still decreased compared to those with non-severe haemophilia and the general male population, regardless of HIV-infection.

Stone age diseases and modern AIDS

The great advantage of being a sexually transmitted disease is the ability to survive and specialize solely on a host species that is present in low numbers and widely distributed so that contact between infected and uninfected organisms by chance is rare. Pathogens of a sparse, but widely distributed host species, must either: i) have an alternative host; ii) be able to survive in a dormant state; or iii) be non-destructive to their host. For the pathogens of a diploid there is a particularly effective strategy, that of being sexually transmitted. Then the hosts' themselves transfer the pathogen.

Transmissible spongiform encephalopathy agent clearance by the immunoaffinity and anion-exchange chromatography steps of the ReFacto manufacturing process

ReFacto (moroctocog alfa), a recombinant factor VIII approved for the treatment of haemophilia A, is produced by a mammalian cell-culture process that includes therapeutic-grade human serum albumin (HSA) in the cell-culture medium. While to date there have been no cases of transmissible spongiform encephalopathy (TSE) resulting from the clinical use of HSA, Wyeth conducted a study to demonstrate that the ReFacto manufacturing process has significant capacity to remove a TSE agent if it were present as a contaminant in the HSA. The immunoaffinity (8A4 Sepharose) and anion-exchange (Q Sepharose) chromatography steps were evaluated for the clearance of the hamster TSE agent, strain 263K. This Good Laboratory Practice study was performed using appropriately qualified, laboratory-scale chromatography systems. Filtered brain homogenate from TSE-infected hamsters was added to loads of both chromatographic columns, and the concentration of TSE agent in the loads and product pools were determined using a validated western blot quantitation method. Replicate chromatography runs were consistent, as demonstrated by the < or =0.7 log(10) difference observed in TSE agent reduction between each pair of runs. The immunoaffinity and anion-exchanges steps demonstrated 3.8 log reduction and >5.2 log reduction respectively. These data provide a high degree of assurance that in the unlikely event of a TSE contamination of the HSA used in the ReFacto cell-culture process, the purification steps have the potential to remove the infectious agent to extremely low levels, thereby significantly reducing the risk to patients receiving ReFacto.

Out of Africa: what can we learn from HIV-2 about protective immunity to HIV-1?

Most people infected with human immunodeficiency virus 2 (HIV-2) do not progress to disease, even though the minority who do cannot be distinguished clinically from HIV-1-infected patients. Here we review what is known about the basis of viral control in HIV-2 infection.

Mortality rates, life expectancy, and causes of death in people with hemophilia A or B in the United Kingdom who were not infected with HIV

Since the 1970s, mortality in the hemophilia population has been dominated by human immunodeficiency virus (HIV) and few reports have described mortality in uninfected individuals. This study presents mortality in 6018 people with hemophilia A or B in the United Kingdom during 1977 to 1998 who were not infected with HIV, with follow-up until January 1, 2000. Given disease severity and factor inhibitor status, all-cause mortality did not differ significantly between hemophilia A and hemophilia B. In severe hemophilia, all-cause mortality did not change significantly during 1977 to 1999. During this period, it exceeded mortality in the general population by a factor of 2.69 (95% confidence interval [CI]: 2.37-3.05), and median life expectancy in severe hemophilia was 63 years. In moderate/mild hemophilia, all-cause mortality did not change significantly during 1985 to 1999, and median life expectancy was 75 years. Compared with mortality in the general population, mortality from bleeding and its consequences, and from liver diseases and Hodgkin disease, was increased, but for ischemic heart disease it was lower, at only 62% (95% CI: 51%-76%) of general population rates, and for 14 other specific causes it did not differ significantly from general population rates. There was no evidence of any death from variant Creutzfeldt-Jakob disease or from conditions that could be confused with it.

Trends in AIDS and Mortality in HIV-Infected Subjects With Hemophilia From 1985 to 2003

OBJECTIVE

To study trends in progression to AIDS, all-cause mortality, and cause-specific mortality (AIDS-related, liver disease, and hemorrhagic complications) over calendar periods with different exposure to highly active antiretroviral therapy (HAART) in a cohort of hemophiliacs in Spain, taking into account the competing risks of the causes of death.

METHODS

Multicenter cohort of HIV-infected hemophiliacs. HIV seroconversion was estimated using mathematic techniques for interval-censored data from 1979 through 1985. Rates of AIDS and cause-specific death were calculated by Poisson regression, allowing for late entry, for the periods 1985 through 1992, 1993 through 1996, 1997 through 2000 (early HAART), and 2001 through 2003 (late HAART), also allowing for competing risks.

RESULTS

Of 585 subjects, 44% were younger than 15 years of age, 82% had severe hemophilia, 86% had type A hemophilia, and the median seroconversion date was October 1982. Calendar period and age at HIV seroconversion strongly influenced AIDS and death rates. Compared with 1993 through 1996, decreases of 75% (relative risk [RR] = 0.25, 95% confidence interval [CI]: 0.14 to 0.43) and 72% (RR = 0.28, 95% CI: 0.12 to 0.63) in the RR of AIDS were observed in early and late HAART. For all-cause mortality, 72% (RR = 0.28, 95% CI: 0.18 to 0.42) and 83% (RR = 0.17, 95% CI: 0.09 to 0.33) decreases were observed by 1997 through 2000 and 2001 through 2003. For liver-related deaths, increases were observed in the late-HAART period (RR = 2.80, 95% CI: 0.94 to 8.36) compared with 1993 through 1996, but using competing risks, this RR was substantially reduced (RR = 1.70, 95% CI: 0.57 to 5.04).

DISCUSSION

Major reductions in AIDS and death rates were observed from 1997 to 2003 in hemophiliacs. These survival improvements are largely attributable to decreases in AIDS-related deaths and have been accompanied by increases in liver disease death rates, which are overestimated if competing risks are not taken into account.

Mortality rates and causes of death among all HIV-positive individuals with hemophilia in Canada over 21 years of follow-up

Many individuals with hemophilia were infected with human immunodeficiency virus (HIV) in the early 1980s through contaminated blood products. Most also were co-infected with hepatitis C virus (HCV). Deaths among the entire cohort of HIV-positive hemophiliacs in Canada up to 2003 are described. Using registry data, we analyzed Kaplan-Meier survival curves, determined the effect of age at HIV seroconversion on mortality, and described cause-specific proportional mortality patterns over time. Of 2427 Canadians with hemophilia, 660 (27.2%) were HIV-positive, of whom 406 (61.5%) died. In contrast, 114 (6.5%) deaths occurred in HIV-negative controls. Median age at HIV seroconversion was 20 (range, < 1-67 years), and median survival was 15.0 years (95% confidence interval, 13.6-16.4 years). Younger age at HIV seroconversion was associated with improved survival; however, this finding was not explained by differences in causes of death across age groups. Following the introduction of highly active antiretroviral therapy, the proportion of deaths due to acquired immune deficiency syndrome has decreased, while the proportion of deaths due to liver disease has increased. There were 1134 HCV-positive individuals, of whom only 444 (39.2%) were also HIV-positive. Liver disease is a growing health concern among many hemophiliacs, not only those who are HIV-positive.

Prevalence and risk factors for heart disease among males with hemophilia

There have been conflicting reports in the literature about the protective effect of hemophilia on the occurrence of ischemic heart disease (IHD). Circulatory disease has been reported as the second most common cause of death in persons with hemophilia in the United States. In addition to diabetes and hypertension, high levels of FVIII, as may occur during factor concentrate infusions, may increase IHD risk in this population. To estimate the prevalence of heart disease and examine factors associated with IHD and other heart diseases among persons with hemophilia, we analyzed data collected from the medical records of 3,422 males with hemophilia living in six U.S. states from 1993 to 1998. Heart disease cases were ascertained from among 2,075 persons who were hospitalized at least once during the 6-year period. Of these, 48 were diagnosed with IHD and 106, with other types of heart disease. The age-specific prevalence of IHD ranged from 0.05% in those under 30 years to 15.2% in those 60 years or older. Hospital discharge rates in males with hemophilia with IHD and other types of heart disease were lower compared to rates in age-matched U.S. males. In our cohort, as in the general population, IHD was independently associated with age, hypertension, diabetes, and hyperlipidemia. Other heart diseases were associated with HIV infection, hypertension, hemophilia B, and diabetes. In summary, persons with hemophilia have unique risk factors such as infusion of factor concentrates and infection with HIV that may predispose them to heart disease as their life expectancy increases.

Social and environmental risk factors in the emergence of infectious diseases

Fifty years ago, the age-old scourge of infectious disease was receding in the developed world in response to improved public health measures, while the advent of antibiotics, better vaccines, insecticides and improved surveillance held the promise of eradicating residual problems. By the late twentieth century, however, an increase in the emergence and re-emergence of infectious diseases was evident in many parts of the world. This upturn looms as the fourth major transition in human-microbe relationships since the advent of agriculture around 10,000 years ago. About 30 new diseases have been identified, including Legionnaires' disease, human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS), hepatitis C, bovine spongiform encephalopathy (BSE)/variant Creutzfeldt-Jakob disease (vCJD), Nipah virus, several viral hemorrhagic fevers and, most recently, severe acute respiratory syndrome (SARS) and avian influenza. The emergence of these diseases, and resurgence of old ones like tuberculosis and cholera, reflects various changes in human ecology: rural-to-urban migration resulting in high-density peri-urban slums; increasing long-distance mobility and trade; the social disruption of war and conflict; changes in personal behavior; and, increasingly, human-induced global changes, including widespread forest clearance and climate change. Political ignorance, denial and obduracy (as with HIV/AIDS) further compound the risks. The use and misuse of medical technology also pose risks, such as drug-resistant microbes and contaminated equipment or biological medicines. A better understanding of the evolving social dynamics of emerging infectious diseases ought to help us to anticipate and hopefully ameliorate current and future risks.

The incidence of factor VIII and factor IX inhibitors in the hemophilia population of the UK and their effect on subsequent mortality, 1977-99

BACKGROUND

Previous studies of the development of inhibitors and their impact on mortality have been small.

OBJECTIVES

To examine the development of inhibitors in people with hemophilia in the UK and their effect on subsequent mortality.

PATIENTS

6078 males with hemophilia A and 1172 males with hemophilia B registered in the UK Haemophilia Centre Doctors' Organisation database, 1977-98.

RESULTS

In severe hemophilia A inhibitors developed at rates of 34.4, 5.2 and 3.8 per 1000 years at ages <5, 5-14 and 15+years; cumulative risks at ages 5 and 75 were 16% and 36%. In hemophilia A the rate of inhibitor development decreased during 1977-90, but increased during the 1990s. In severe hemophilia B inhibitors developed at rates of 13.3 and 0.2 per 1000 years at ages <5 and 5+ and cumulative risks at ages 5 and 75 were 6% and 8%. With HIV, inhibitor development did not increase mortality. In severe hemophilia without HIV, inhibitor development doubled mortality during 1977-92, but during 1993-99 mortality was identical with and without inhibitors. In severe hemophilia without HIV but with inhibitors, mortality from causes involving bleeding decreased during 1977-99 (P = 0.001) as did mortality involving intracranial hemorrhage (P = 0.007).

CONCLUSIONS

These data provide estimates of the rate of inhibitor development in hemophilia A and hemophilia B, and they show that the rate of inhibitor development has varied over time, although the reasons for this remain unclear. They also show that in severe hemophilia the substantial increase in mortality previously associated with inhibitors is no longer present.

Blood Products for Hemophilia

Hemophilia is an inherited bleeding disorder, which in its severe form is characterized by recurrent hemarthrosis and internal bleeding. In the absence of effective treatment the prognosis is poor, but the development of blood products in the last few decades has transformed the outlook, and patients can now live essentially normal lives. Treatment options vary around the world, with cryoprecipitate still the mainstay of therapy in many developing countries. Many patients were infected with hepatitis and/or HIV through the use of coagulation factor concentrates before the introduction of physical methods of viral inactivation in the mid-1980s. In more affluent countries, the debate in recent years has focused on the relative merits of plasma versus recombinant products. Coagulation factor concentrates are expensive, and cost-benefit and quality-of-life studies will assume an increasing importance in guiding the selection of products. Looking to the future, genetic engineering offers the potential to create coagulation factors with enhanced properties, such as reduced immunogenicity and prolonged half-life. Transgenic animals are a potential source of therapeutic materials. Several trials of gene therapy for hemophilia are already underway.

The effect of highly active antiretroviral therapy for HIV on the anti-HCV specific humoral immune response

The effect of highly active antiretroviral therapy (HAART) on HCV replication is controversial, with some studies reporting no effect and others increases, reductions and even clearances of HCV RNA after treatment. In this study, the effect of HAART was investigated on the titre of anti-HCV specific antibodies and on the relationship between these antibodies and HCV RNA level in a cohort of 24 patients with inherited bleeding disorders. A significant inverse correlation between antibodies to both total HCV proteins and HCV RNA (R = -0.42, P = 0.05) and between antibodies to HCV envelope glycoproteins and HCV RNA (R = -0.54, P = 0.01) was observed pre-HAART. The relationship disappeared or was obscured after therapy (R = 0.24, P = 0.30 and R = 0.16, P = 0.50, respectively). Thus, we show that HAART affects the HCV specific humoral immune responses without affecting the HCV RNA level.

Retrospective analysis of 1312 patients with haemophilia and related disorders in a single Chinese institute

With 1.3 billion people, China has the largest population in the world, and therefore has the largest population of persons with haemophilia (PWH). As there is no national registry for haemophilia, it is difficult to ascertain how many PWH have actually been diagnosed. Between January 1983 and June 2002, 1312 patients with coagulation disorders were referred to our hospital, and 1190 patients were evaluable. Among them, 1069 (89.8%) patients had haemophilia, 68 had vWD, 20 had factor XI deficiency, 10 had acquired factor VIII inhibitor and 23 had other coagulation disorders. Of the 1069 PWH, 14.7% were unclassified, 38.4% severe, 35.7% moderate and 11.1% mild. If the unclassified cases were excluded, 45.1% were severe, 41.9% moderate and 13.0% mild. Twenty-nine of the 68 vWD patients had vWF:Ag <5%, and subcategorized as type 3 vWD. Because vWF multimer analysis was not performed in our centre, the remaining vWD patients were not subdivided.

Treatment of patients with haemophilia and inhibitory antibodies

The development of inhibitory antibodies is a complication which arise in approximately 10% of patients with haemophilia A. The underlying genetic mutation is the single most important predisposing cause, although other risk factors have been identified. Periodic screening for inhibitors is a vital aspect of haemophilia care. The consequences of inhibitor development are very significant in terms of morbidity and cost. Several agents are now available for control of bleeding, but these are often very expensive. The most useful agents include recombinant activated factor VII, prothrombin complex concentrates and porcine factor VIII. It is possible to suppress antibody production with immune tolerance, which is successful in approximately 85% of cases and relapse is rare.

Control of bleeding in patients with haemophilia A with inhibitors: a systematic review

This paper reports a systematic review of the best available evidence of clinical effectiveness in the treatment of acute bleeding in haemophilia A patients with inhibitors. Because of the lack of randomized controlled trials (RCTs) on this topic, broad inclusion criteria with regard to study design were applied in order to assess the best available evidence for each intervention. Because of the clinical and methodological heterogeneity of the evidence, it was not appropriate to pool data across studies; instead, data were synthesized using tabulation and qualitative narrative assessment. No evidence was found to support the use of high-dose factor VIII (FVIII) in bleeding episodes. However in surgery it was found to be highly successful (100%) for low-titre, low-responding inhibitors although not reliable for high-responding inhibitors. Porcine FVIII (pFVIII) was effective in the control of severe bleeding episodes with high-titre or high-responding inhibitors (100%) and in 60-90% of surgical procedures. Activated prothrombin complex concentrates (APCCs) appear to be more effective than prothrombin complex concentrates (PCCs) in the control of mild to severe bleeding episodes. There was no good evidence for the use of PCCs in surgery. APCCs controlled bleeding in approximately 90% of surgical episodes. Recombinant factor VIIa (rFVIIa) controlled 70-100% of mild to severe bleeding episodes with high-responding inhibitors, and achieved better results when used early. It was effective in 60-100% of surgical episodes. Doses varied from study to study, and side-effects from mild to infrequent but serious adverse events were reported. The quality of the evidence is variable. Limited evidence relating to other treatment options is also included in the review.

The chemical bases of the various AIDS epidemics: recreational drugs, anti-viral chemotherapy and malnutrition

In 1981 a new epidemic of about two-dozen heterogeneous diseases began to strike non-randomly growing numbers of male homosexuals and mostly male intravenous drug users in the US and Europe. Assuming immunodeficiency as the common denominator the US Centers for Disease Control (CDC) termed the epidemic, AIDS, for acquired immunodeficiency syndrome. From 1981-1984 leading researchers including those from the CDC proposed that recreational drug use was the cause of AIDS, because of exact correlations and of drug-specific diseases. However, in 1984 US government researchers proposed that a virus, now termed human immunodeficiency virus (HIV), is the cause of the non-random epidemics of the US and Europe but also of a new, sexually random epidemic in Africa. The virus-AIDS hypothesis was instantly accepted, but it is burdened with numerous paradoxes, none of which could be resolved by 2003: Why is there no HIV in most AIDS patients, only antibodies against it? Why would HIV take 10 years from infection to AIDS? Why is AIDS not self-limiting via antiviral immunity? Why is there no vaccine against AIDS? Why is AIDS in the US and Europe not random like other viral epidemics? Why did AIDS not rise and then decline exponentially owing to antiviral immunity like all other viral epidemics? Why is AIDS not contagious? Why would only HIV carriers get AIDS who use either recreational or anti-HIV drugs or are subject to malnutrition? Why is the mortality of HIV-antibody-positives treated with anti-HIV drugs 7-9%, but that of all (mostly untreated) HIV-positives globally is only 1.4%? Here we propose that AIDS is a collection of chemical epidemics, caused by recreational drugs, anti-HIV drugs, and malnutrition. According to this hypothesis AIDS is not contagious, not immunogenic, not treatable by vaccines or antiviral drugs, and HIV is just a passenger virus. The hypothesis explains why AIDS epidemics strike non-randomly if caused by drugs and randomly if caused by malnutrition, why they manifest in drug- and malnutrition-specific diseases, and why they are not self-limiting via anti-viral immunity. The hypothesis predicts AIDS prevention by adequate nutrition and abstaining from drugs, and even cures by treating AIDS diseases with proven medications.

Prevalence of hepatitis C virus infection and risk for hepatocellular carcinoma and non-Hodgkin lymphoma in AIDS

Hepatitis C virus (HCV) infection is highly prevalent in some subpopulations with AIDS. HCV is linked to hepatocellular carcinoma (HCC) and possibly non-Hodgkin lymphoma (NHL), but the impact of AIDS on these associations is uncertain. We used U.S. registry data to study HCC and NHL risk in 304,411 adults with AIDS, comparing cohort subgroups with high prevalence (hemophiliacs and injection drug users) or low prevalence (homosexual men, heterosexuals, and others) of HCV infection. The ratio of observed to expected cancer cases (standardized incidence ratio [SIR]) measured risk relative to the general population. Sixty-one HCC cases were observed (SIR, 7.5; 95% confidence interval, 5.7-9.6). Risk for HCC was higher in subgroups with high prevalence of HCV infection than in subgroups with low prevalence of HCV infection (SIR: 11.4 versus 5.5, respectively; p =.004). Subjects developed the following NHL grades: low, 35 cases; intermediate, 1035 cases; high, 784 cases; and unspecified, 1395 cases. For each NHL grade, SIRs were highest in subgroups with low prevalence of HCV infection. These data suggest an effect of HCV infection on HCC risk among adults with AIDS. On the other hand, NHL risk was not higher for groups in whom HCV infection was prevalent.

The incidence of lymphoma in the UK haemophilia population between 1978 and 1999

OBJECTIVE

To determine the incidence of non-Hodgkin's lymphoma (NHL) and Hodgkin's disease (HD) in the UK haemophilia population during the 22 year period 1978-1999.

DESIGN AND METHODS

An analysis of patient data included on the UK Haemophilia Centre Doctors' Organisation lymphoma register. The number of cases of NHL and HD occurring in HIV-positive and negative patients in each 3-year period were compared with the expected incidence in the general male population.

RESULTS

Eighty-nine cases of lymphoma were identified. Seventy-two cases (81%) occurred in HIV-positive patients (67 NHL, five HD), and 17 cases (19%) in HIV-negative patients (nine NHL, eight HD). The incidence of NHL in the HIV-positive cohort was significantly increased, with a ratio of observed to expected cases of 83.92 (P < 0.001) in the period 1985-1996. The ratio reduced to 42.15 during the period 1997-1999, presumably as a consequence of the introduction of highly active antiretroviral therapy (HAART). There was a significant excess of HD in HIV-positive patients, with an observed to expected ratio of 10.50 between 1985 and 1999 (based on five cases, P < 0.001). During the whole observation period, there was a significant excess of HD in HIV-negative patients, with an observed to expected ratio of 2.66 (based on eight cases, P < 0.05).

CONCLUSION

The incidence of lymphoma is significantly higher in HIV-positive UK haemophilia patients compared with HIV-negative individuals. Since the introduction of HAART, the incidence of lymphoma has tended to fall in the HIV-positive group.

Factors predictive of death among HIV-uninfected persons with haemophilia and other congenital coagulation disorders

Historically, the leading cause of death among persons with haemophilia and other congenital coagulation disorders was uncontrolled bleeding. Mortality was associated with severe deficiency of coagulation factors VIII or IX and especially with high-titre antifactor neutralizing antibodies (inhibitors). The catastrophic contamination of plasma donor pools with human immunodeficiency virus (HIV) resulted in acquired immunodeficiency syndrome replacing haemorrhage as the leading cause of death among persons with haemophilia. Rather little has been written, however, about mortality among those not infected with HIV. The objective of this study was to identify conditions associated with all-cause mortality among HIV-uninfected patients who were followed for a mean of 8.8 years in the Multicentre Hemophilia Cohort Study. Among the 364 children (mean age 8 years), there were four deaths; two related to cancer, one to trauma, and the fourth to haemorrhage, end-stage liver disease and sepsis. Among the 387 HIV-uninfected adults (mean age 35 years) there were 29 deaths, with haemorrhage the leading cause of death, followed by hepatic, stroke and cancer deaths. Prognostic factors for all-cause mortality among the adults included haemophilia Type A with neutralizing antibodies [age-adjusted relative rate (RR) 3.1, 95% confidence interval (CI) 1.4-6.9] and serologic evidence of both hepatitis B and C virus (RR 4.1, 95% CI 0.97-17.6). Although hepatitis C viral load was slightly lower in patients with hepatitis B virus surface antigenaemia, it was unrelated to vital status. We conclude that causes of death and prognostic factors for current HIV-uninfected haemophilia patients are similar to those noted before the HIV epidemic. Better understanding, prevention and control of neutralizing antibodies and hepatitis infections may substantially improve longevity for people with haemophilia.

Adaptor protein-2 exhibits alpha 1 beta 1 or alpha 6 beta 1 integrin-dependent redistribution in rhabdomyosarcoma cells

Downregulation of several signaling pathways, such as those stimulated by growth factor receptors, occurs by internalization of signaling receptors through clathrin-coated pits. The first step in internalization or endocytosis is interaction with AP-2, which results in coated pit formation by assembly of clathrin to AP-2. Changes in endocytosis are reflected in the distribution of AP-2 molecules at the cell surface. Integrins are receptors which mediate attachment to the extracellular matrix and also stimulate numerous intracellular signaling pathways; however, it is not known how signaling through integrins is terminated or downregulated. Endocytosis through clathrin-coated pits offers an attractive mechanism for this. This work explores the relationship between AP-2 and beta(1) integrins. RD cells grown for 24 h on collagen or laminin exhibit a redistribution of AP-2 to the cell periphery relative to those grown on fibronectin or polylysine. The total AP-2 protein levels in the cells are unaffected. Blocking alpha(1)beta(1) integrin ligand binding on collagen prevents this redistribution fully. On laminin where alpha(1)beta(1) and alpha(6)beta(1) integrins are engaged, both receptors must be simultaneously blocked to prevent AP-2 redistribution, confirming that the redistribution depends on the specific engagement of the receptors. Immunofluorescence reveals that the majority of alpha(1)beta(1) integrins colocalize with alpha(6)beta(1) integrins in linear structures identified as focal adhesions. A separate fraction of alpha(1)beta(1) integrins colocalize with AP-2 in coated pits. Interestingly, alpha(6)beta(1) integrins are not located in coated pits, demonstrating that integrin colocalization with AP-2 is not necessary to induce redistribution of AP-2.

The Biology and Evolution of HIV

▪ Abstract  This review examines the current state of knowledge about HIV/AIDS in terms of its origins, pathogenesis, genetic variation, and evolutionary biology. The HIV virus damages the host's immune system, resulting in AIDS, which is characterized by immunodeficiency, opportunistic infections, neoplasms, and neurological problems. HIV is a complex retrovirus with a high mutation rate. This mutation rate allows the virus to evade host immune responses, and evidence indicates that selection favors more virulent strains with rapid replication. While a number of controversial theories attempt to explain the origin of HIV/AIDS, phylogenetic evidence suggests a zoonotic transmission of HIV to humans and implicates the chimpanzee (Pan troglodytes troglodytes) as the source of HIV-1 infection and the sooty mangabey as the source of HIV-2 infection in human populations. New therapies provide hope for increased longevity among people living with AIDS, but the biology of HIV presents significant obstacles to finding a cure and/or vaccine. HIV continues to be a threat to the global population because of its fast mutation rate, recombinogenic effect, and its use of human defenses to replicate itself.

The natural history of chronic hepatitis C in a cohort of HIV-negative Italian patients with hereditary bleeding disorders

This study looked at 102 anti-hepatitis C virus (HCV)-positive, hepatitis B virus (HBV)-negative, and HIV-negative patients (median age, 45.1 years; range, 15-71) affected by hereditary bleeding disorders who have been infected with HCV for 15 to 34 years (median, 25.1). All these patients were infected before the mid 1980s because of non-virally inactivated pooled blood products. Fourteen patients (13.7%) were HCV-RNA negative with no signs of liver disease and were considered to have cleared the virus. Eighty-eight patients (86.3%) were HCV-RNA positive. The HCV genotype distribution was 1a in 20.5%, 1b in 36.4%, 2 in 17.0%, 3 in 15.9%, 4 in 3.4%, and mixed in 6.8% of cases. Twenty-four patients (23.5%) had serum cryoglobulins, symptomatic in 4 cases, and associated with liver disease and with genotype 1. Among the 88 HCV-RNA-positive patients, 15 (17.0%) had normal alanine aminotransferase levels and abdominal ultrasound, 61 (69.3%) had nonprogressive chronic hepatitis, and 12 (13.7%) had severe liver disease (6 [6.9%] liver cirrhosis, 4 [4.5%] hepatic decompensation, and 2 [2.3%] hepatocellular carcinoma) after a follow-up period of 25 years. There were 3 (3.4%) liver-related deaths. HCV genotype 1, patient's age at evaluation, duration of infection, and severity of congenital bleeding disorder were associated with more advanced liver disease. The results confirm the slow progression of HCV infection in HIV-negative hemophiliacs.

Influence of human immunodeficiency virus infection on the course of hepatitis C virus infection: a meta-analysis

Studies have shown that rates of liver disease are higher in persons who are coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) than they are in persons with HCV alone, but estimates of risk vary widely and are based on data for dissimilar patient populations. We performed a meta-analysis to quantify the effect of HIV coinfection on progressive liver disease in persons with HCV. Eight studies were identified that included outcomes of histological cirrhosis or decompensated liver disease. These studies yielded a combined adjusted relative risk (RR) of 2.92 (95% confidence interval [CI], 1.70-5.01). Of note, studies that examined decompensated liver disease had a combined RR of 6.14 (95% CI, 2.86-13.20), whereas studies that examined histological cirrhosis had a pooled RR of 2.07 (95% CI, 1.40-3.07). There is a significantly elevated RR of severe liver disease in persons who are coinfected with HIV and HCV. This has important implications for timely diagnosis and consideration of treatment in coinfected persons.

Mathematical biology and medical statistics: contributions to the understanding of AIDS epidemiology

Some of the many ways in which mathematical biology and statistics have been used in investigating the acquired immunodeficiency syndrome (AIDS) epidemic are reviewed. Aspects of the spread of the disease via social and sexual networks are discussed. The different kinds of data involved are critically compared. Some studies of the incubation period are briefly reviewed and some comments made on the role of adherence to therapy.

Immune tolerance induction in hemophilia patients with inhibitors: costly can be cheaper

The development of inhibitory antibodies to factor VIII (FVIII) occurs in approximately 30% to 40% of patients with severe hemophilia A. Management options for patients with inhibitor include eradicating it via immune tolerance induction (ITI) or treating bleeding episodes with large quantities of hemostatic agents. ITI is costly, approaching $1 million for the average 5-year-old, but if successful results in improved clinical outcomes. We constructed a decision analysis using the Markov process to model expected clinical outcomes and costs over a lifetime for a typical 5-year-old hemophiliac with high inhibitor levels. Estimates of relevant variables were based on a thorough review of the medical literature. Outcomes modeled included total lifetime costs as well as life expectancy. The decision analytic model revealed that the ITI strategy was associated with an increase in projected life expectancy of 4.6 years. Total estimated lifetime costs for the ITI strategy were approximately $1.7 million less per patient. Sensitivity analyses over clinically and economically reasonable ranges did not change these findings. The insight that ITI can achieve an improved clinical outcome while being cost-saving is not reflected in many current treatment regimens. This example also illustrates that expensive therapy for patients with a chronic disease may be cost effective when analyzed from a societal perspective over the patient's lifetime. This finding has important policy implications for medical decision makers at many levels and reinforces the need to undertake pharmacoeconomic analyses and choose therapies from a long-term, societal perspective.

Haemophilia care in central Scotland 1980-94. I. Demographic characteristics, hospital admissions and causes of death

To estimate the resources required to manage patients with haemophilia in Scotland, we studied the demographic features, hospital admissions and causes of deaths for individuals with haemophilia A and B and von Willebrand disease, treated with blood products, during the period 1980-94 living in central Scotland. Data were obtained from 413 adults and children (93% ascertainment). The age distribution in 1980 revealed a paucity of individuals over 60 years but the number in this age group increased over the study period. Of those with haemophilia A and B, 63 and two respectively, became HIV positive. Hospital admissions rose from 103 to 168 per annum; the number of annual bed days utilized also increased, but there was marked annual fluctuation (790-1832). The rate of admission was greater for those with severe haemophilia A and this increased during the 15-year period mainly due to the clinical consequences of human immunodeficiency virus (HIV) and hepatitis C virus (HCV). The admission rate for haemophilia B was significantly lower than that for haemophilia A, and was similar for all degrees of severity of the disorder. Throughout the 15-year period the incidence of admissions for acute bleeds was constant, as was the average duration in hospital. For those with a factor VIII inhibitor, the rate of admission was about double the rate of those without an inhibitor, although the duration of hospital stay was similar for both groups. There were 61 deaths; the death rate increased during the study period principally due to HIV and HCV, and 12 patients died from haemorrhage. We conclude that: (i) the life expectancy for haemophiliacs in Scotland was generally increasing, although HIV and HCV caused increasing mortality and morbidity (as shown by the increase in hospital admissions); (ii) hospital bed usage for the treatment of acute bleeds continued to be required, but fluctuated greatly; and (iii) the clinical impression that haemophilia B is less clinically severe than haemophilia A is confirmed by objective data. The planning implications for haemophilia care in Scotland and similar countries are discussed.

Immune tolerance induction in hemophilia patients with inhibitors: costly can be cheaper

The development of inhibitory antibodies to factor VIII (FVIII) occurs in approximately 30% to 40% of patients with severe hemophilia A. Management options for patients with inhibitor include eradicating it via immune tolerance induction (ITI) or treating bleeding episodes with large quantities of hemostatic agents. ITI is costly, approaching $1 million for the average 5-year-old, but if successful results in improved clinical outcomes. We constructed a decision analysis using the Markov process to model expected clinical outcomes and costs over a lifetime for a typical 5-year-old hemophiliac with high inhibitor levels. Estimates of relevant variables were based on a thorough review of the medical literature. Outcomes modeled included total lifetime costs as well as life expectancy. The decision analytic model revealed that the ITI strategy was associated with an increase in projected life expectancy of 4.6 years. Total estimated lifetime costs for the ITI strategy were approximately $1.7 million less per patient. Sensitivity analyses over clinically and economically reasonable ranges did not change these findings. The insight that ITI can achieve an improved clinical outcome while being cost-saving is not reflected in many current treatment regimens. This example also illustrates that expensive therapy for patients with a chronic disease may be cost effective when analyzed from a societal perspective over the patient's lifetime. This finding has important policy implications for medical decision makers at many levels and reinforces the need to undertake pharmacoeconomic analyses and choose therapies from a long-term, societal perspective.

Two decades of HIV infection in a cohort of haemophilic individuals: clinical outcomes and response to highly active antiretroviral therapy

OBJECTIVES

Many haemophilic individuals infected with HIV died before receiving antiretroviral therapy (ART). Most who remain alive are chronically infected with hepatitis C virus (HCV), which has implications for their prognosis and choice of ART. The clinical status of a cohort of HIV-positive haemophilic men is reported together with their response to highly active antiretroviral therapy (HAART).

DESIGN

Longitudinal cohort study.

SETTING

A comprehensive care haemophilia centre.

PATIENTS

A group of 111 haemophilic men who seroconverted to HIV in the period 1979 to 1985.

RESULTS

The cohort has been followed since 1979. By 30 April 1999, 57 of the 111 men had developed AIDS and 65 had died: Kaplan-Meier rates of 57.0% [95% confidence interval (CI) 46.9-67.0) and 65.1% (95% CI 52.7-77.4) by 19.5 years, respectively. AIDS rates have declined since 1997 but death rates have remained high, largely owing to deaths from non-HIV-related causes. Thirty-five patients remain alive and under follow-up at the clinic. The 28 men who had received ART had lower CD4 cell counts than the seven patients who had not received ART, but the two groups were otherwise similar. In total, 21 patients are known to have started HAART while under care at the centre. By 10-12 months after starting HAART, viral loads dropped by 2.06 log10 copies/ml and CD4 cell counts increased by 60 x 10(6) cells/l. In 10 out of 18 patients with viral loads initially > 400 copies/ml, a viral load below this level was attained; four had changed therapy at the time.

CONCLUSIONS

While the decision to initiate HAART in haemophilic men should be made carefully because of the possible adverse events, our results suggest that a good response rate was achieved in this group of men.

Cancer risk among men with, or at risk of, HIV infection in southern Europe

OBJECTIVE

To evaluate the cancer risk in southern European men with, or at risk of, HIV infection.

DESIGN

An analysis of longitudinal data to assess time-dependent rare events.

METHODS

Data from a cohort of HIV seroconverters, and from two hospital-based HIV seroprevalent cohorts were combined and analysed. The number of cancer cases observed was compared with the expected number, obtained from cancer incidence rates among men in the general population. Age-standardized incidence ratios (SIR) and their 95% confidence intervals (CI) were computed.

RESULTS

A total of 19,609 person-years of observation were accumulated among HIV-positive men, and 7957 person-years among HIV-negative men. Among HIV-positive men, statistically significant increased SIR were seen for Hodgkin's disease (HD) (SIR = 8.7), liver cancer (SIR = 11.0), and cancer of the salivary glands (SIR = 33.6). An excess of lung cancer was seen among intravenous drug users (IDU), but not among homosexual men. When the risk of all non-AIDS-defining cancers was considered, HIV-positive men had a nearly twofold excess (95% CI: 1.2-2.8). A risk of similar magnitude emerged among HIV-negative IDU (95% CI: 1.0-4.5), largely attributable to lung cancer and HD.

CONCLUSION

These findings confirm that HIV infection increases the risk of HD, whereas they suggest that the risk of hepatocellular carcinoma may also be enhanced by HIV infection. The observation of an elevated risk of lung cancer in both HIV-positive and HIV-negative IDU points to personal behaviours unrelated to HIV infection.