Effects of HIV infection on age and cause of death for persons with hemophilia A in the United States

Racial and ethnic differences in reported haemophilia death rates in the United States

INTRODUCTION

People with haemophilia's life expectancies have improved over time. Whether progress has been experienced equitably is unknown.

AIM

To examine recorded haemophilia death (rHD) rates according to race and ethnicity in the United States (US).

METHODS

In this cohort study, rHDs were examined with US National Vital Statistics' 1999-2020 Multiple Cause-of-Death data. rHD was defined as having a haemophilia A (D66) or B (D67) ICD-10 code in the death certificate (underlying or multiple causes of death). Age-adjusted rHD rates were compared with age-adjusted rate ratios (aRR) and 95% Confidence Intervals (CI).

RESULTS

There were 3115 rHDs in males with an rHD rate of 0.98 per 1 million males. Between 1999 and 2020, rHD rates declined by 46% in NH (Non-Hispanic) White, 44% in NH Black (aRR = 0.56, 95%CI 0.43, 0.74), and 42% in Hispanic (aRR = 0.58, 95%CI 0.39, 0.88) males. However, rHD rates remained higher and were on average 30% greater in NH Black versus NH White males (aRR = 1.30 95% CI 1.16, 1.46). Among males with rHD, the median age at death rose from 54.5 to 65.5 years between 1999 and 2020 and was 12 years lower in NH Black (56 years) versus NH White (68 years) males in 2010-2020. There were 930 females with rHD, with an age-adjusted rate of 0.22 per 1 million females, which was consistent between 1999 and 2020.

CONCLUSION

Reported haemophilia-death rates improved in males across all race/ethnicities, but rates were higher Black versus White males. Given the inherent limitations of the current study's data source, further investigation of survival rates and disparities in haemophilia are needed.

Patient-centered pharmacovigilance: priority actions from the inherited bleeding disorders community

Pharmacovigilance, the science and practice of monitoring the effects of medicinals and their safety, is the responsibility of all stakeholders involved in the development, manufacture, regulation, distribution, prescription, and use of drugs and devices. The patient is the stakeholder most impacted by and the greatest source of information on safety issues. It is rare, however, for the patient to take a central role and exert leadership in the design and execution of pharmacovigilance. Patient organizations in the inherited bleeding disorders community are among the most established and empowered, particularly in the rare disorders. In this review, two of the largest bleeding disorders patient organizations, Hemophilia Federation of America (HFA) and National Hemophilia Foundation (NHF), offer insights into the priority actions required of all stakeholders to improve pharmacovigilance. The recent and ongoing increase in incidents raising safety concerns and a therapeutic landscape on the cusp of unprecedented expansion heighten the urgency of a recommitment to the primacy of patient safety and well-being in drug development and distribution.

Plain Language Summary

Patients at the center of product safety Every medical device and therapeutic product has potential benefits and harms. The pharmaceutical and biomedical companies that develop them must demonstrate that they are effective, and the safety risks are limited or manageable, for regulators to approve them for use and sale. After the product has been approved and people are using it in their daily lives, it is important to continue to collect information about any negative side effects or adverse events; this is called pharmacovigilance. Regulators, like the United States (US) Food and Drug Administration, the companies that sell and distribute the products, and healthcare professionals who prescribe them are all required to participate in collecting, reporting, analyzing, and communicating this information. The people with the most firsthand knowledge of the benefits and harms of the drug or device are the patients who use them. They have an important responsibility to learn how to recognize adverse events, how to report them, and to stay informed of any news about the product from the other partners in the pharmacovigilance network. Those partners have a crucial responsibility to provide clear, easy-to-understand information to patients about any new safety concerns that come to light. The community of people with inherited bleeding disorders has recently encountered problems with poor communication of product safety issues, prompting two large US patient organizations, National Hemophilia Foundation and Hemophilia Federation of America, to hold a Safety Summit with all the pharmacovigilance network partners. Together they developed recommendations to improve the collection and communication of information about product safety so that patients can make well-informed, timely decisions about their use of drugs and devices. This article presents these recommendations in the context of how pharmacovigilance is supposed to work and some of the challenges encountered by the community.

Therapeutic and technological advancements in haemophilia care: Quantum leaps forward

INTRODUCTION

Recent technological innovations in haemophilia have advanced at an astounding pace, including gene therapy programmes and bioengineered molecules for prophylaxis, products that reduce treatment burden through half-life extension, unique mechanisms of action, and subcutaneous administration. Additional technological advancements have emerged that are anticipated to further transform haemophilia care.

AIM

Review new and emerging haemophilia therapies, including replacement and bypassing products, digital applications, utilisation of big data, and personalised medicine.

METHODS

Data were obtained from peer-reviewed presentations/publications, and ongoing studies in haemophilia, ultrasonography, and artificial intelligence (AI).

RESULTS

Available treatments include new recombinant factors VIII (FVIII) and IX (FIX), extended half-life FVIII/IX products, a new FVIIa product for inhibitor patients, and a FVIIIa-mimetic. Several novel therapeutics are in clinical trials, including FVIIIa mimetics and inhibitors of naturally-occurring anticoagulants. Ongoing gene therapy trials suggest that a single vector infusion using an optimised construct can produce factor activity that reduces bleeding to near zero for years. Today, persons with haemophilia (PwH) approach a lifespan comparable to that of the general population, presenting treatment challenges for age-related co-morbidities. Technological innovations have broadened beyond therapeutics to include large database analyses utilising remote data collection with handheld devices, and to tailor AI applications. Current development efforts include patient-performed ultrasonography, algorithms for scan interpretation, and point-of-care haemostatic testing devices.

CONCLUSIONS

We have entered a golden age for haemophilia treatment and care with wide-ranging advancements targeting improved quality of life (QoL). Future-focused efforts by clinical and patient communities may provide equitable access and care for people impacted by haemophilia worldwide.

Impacts of symptomatic HIV infection on In-Hospital Cardiopulmonary Resuscitation Outcomes: A Population-Based Cohort Study in South Korea

Background

The impacts of human immunodeficiency virus (HIV) infection on survival outcomes after in-hospital cardiopulmonary resuscitation (ICPR) remains controversial. This study aimed to investigate the impacts of HIV infection on both short-term and long-term outcomes after ICPR.

Methods

This nationwide, population-based cohort study used data taken from the South Korean National Health Insurance Service database. All adult (≥18 years old) patients who experienced ICPR between January 1, 2010, and December 31, 2019, were included.

Results

A total of 298,676 adult patients who underwent ICPR were initially included in the analysis. Among them, 586 (0.2%) patients were assigned to the PWH group (patients with symptomatic HIV infection), while 298,090 (99.8%) patients were assigned to the control group. After 1:10 propensity score (PS) matching, 586 patients in the PWH group and 5,845 patients in the control group were included in the analysis. Logistic regression analysis after PS matching showed that the PWH group had a 20% lower live discharge rate after ICPR compared to the control group (odds ratio: 0.80, 95% confidence interval [CI]: 0.65, 0.97; P=0.024). However, Cox regression analysis after PS matching showed that the risks of 6-month survival (hazard ratio [HR]: 1.01, 95% CI: 0.93, 1.11; P=0.768) and 1-year survival (HR: 1.02, 95% CI: 0.93, 1.11; P=0.702) were not significantly different between the PWH and control groups.

Conclusion

Although the PWH group showed lower live discharge rates compared to the control group after ICPR, long-term survival outcomes from 6 months and 1 year were not significantly different.

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.

Causes of death and mortality trends related to hemophilia in Brazil, 1999 to 2016

INTRODUCTION

Multiple cause of death methodology enhances mortality studies beyond the traditional underlying cause of death approach.

AIM

This study aims to describe causes of death and mortality issues related to haemophilia with the use of multiple-cause-of-death methodology.

METHODS

Annual male haemophilia mortality data was extracted from the public multiple-cause-of-death databases of the Mortality Information System, searching deaths included in rubrics D66 "hereditary factor VIII deficiency" (haemophilia A), and D67 "hereditary factor IX deficiency" (Haemophilia B) of the International Classification of Diseases, Tenth Revision, and processed by the Multiple Cause Tabulator.

RESULTS

In Brazil, from 1999 to 2016, a total of 927 male deaths related to haemophilia occurred during the 18 year period, of which 418 (45,1 %) as underlying cause, and 509 (54,9 %) as associated cause of death. The leading associated cause of 418 deaths of haemophilia as underlying cause was hemorrhage (52.6%), half of which intracranial hemorrhage. Infectious and parasitic diseases accounted for 40,5% as the underlying causes of 509 deaths where haemophilia was an associated cause, where human immunodeficiency virus disease prevailed, however falling from 37,0% to 19.7%, and viral hepatitis increased from 6.0% to 7.9%; diseases of the circulatory system, increased from 13.5% to 18.4%, including intracranial hemorrhage from 5.7% to 7.0%, and neoplasms, from 8,5% to 13.2%, respectively from 1999-2007 to 2008-2016, followed as main underlying causes.

CONCLUSION

Hemorrhages, mainly intracranial hemorrhage, human immunodeficiency virus disease, and viral hepatitis are the chief prevention goals aiming at the control of haemophilia mortality.

Inhibitors and mortality in persons with nonsevere hemophilia A in the United States

Although persons with nonsevere hemophilia A (NSHA) account for about one-half of the hemophilia A population, epidemiological data in this subset of individuals are scarce. We set out to describe the clinical characteristics of persons with NSHA with inhibitors, and to determine mortality rates, predictors of mortality, and primary causes of death in persons with NSHA in the United States over a 9-year period (2010-2018). We queried the American Thrombosis and Hemostasis Network dataset (ATHNdataset) for information on demographics, inhibitor status, and date and cause of death. A total of 6624 persons with NSHA (86.0% men; 14.0% women) were observed for an average of 8.5 years; total 56 119 person-years . The prevalence of inhibitors was 2.6% (n = 171), occurring at a median age of 13 years. At the end of follow-up, 136 persons died at a median age of 63 years; an age-adjusted mortality rate of 3.3 deaths per 1000 person-years. Three deaths occurred in inhibitor participants. Presence of inhibitors was not associated with increased mortality risk (hazard ratio [HR], 0.7, 95% confidence interval [CI], 0.2-2.3). Factors independently associated with increased risk of death (HR, 95% CI) were the following: age (10-year increase) (2.1, 2.0-2.4); male (2.6, 1.0-6.4); hepatitis C (2.2, 1.5-3.1); and HIV (3.6, 2.2-6.0). The most common primary cause of death was malignancy (n = 27, 20.0%). In persons with NSHA, the development of inhibitors occurred at an early age and was not associated with increased mortality.

Epidemiological characteristics of HIV infected Korean: Korea HIV/AIDS Cohort Study

OBJECTIVES

To manage evidence-based diseases, it is important to identify the characteristics of patients in each country.

METHODS

The Korea HIV/AIDS Cohort Study seeks to identify the epidemiological characteristics of 1,442 Korean individuals with human immunodeficiency virus (HIV) infection (12% of Korean individuals with HIV infection in 2017) who visited 21 university hospitals nationwide. The descriptive statistics were presented using the Korea HIV/AIDS cohort data (2006-2016).

RESULTS

Men accounted for 93.3% of the total number of respondents, and approximately 55.8% of respondents reported having an acute infection symptom. According to the transmission route, infection caused by sexual contact accounted for 94.4%, of which 60.4% were caused by sexual contact with the same sex or both males and females. Participants repeatedly answered the survey to decrease depression and anxiety scores. Of the total participants, 89.1% received antiretroviral therapy (ART). In the initial ART, 95.3% of patients were treated based on the recommendation. The median CD4 T-cell count at the time of diagnosis was 229.5 and improved to 331 after the initial ART. Of the patients, 16.6% and 9.4% had tuberculosis and syphilis, respectively, and 26.7% had pneumocystis pneumonia. In the medical history, sexually transmitted infectious diseases showed the highest prevalence, followed by endocrine diseases. The main reasons for termination were loss to follow-up (29.9%) and withdrawal of consent (18.7%).

CONCLUSIONS

Early diagnosis and ART should be performed at an appropriate time to prevent the development of new infection.

DeepDeath: Learning to predict the underlying cause of death with Big Data

Multiple cause-of-death data provides a valuable source of information that can be used to enhance health standards by predicting health related trajectories in societies with large populations. These data are often available in large quantities across U.S. states and require Big Data techniques to uncover complex hidden patterns. We design two different classes of models suitable for large-scale analysis of mortality data, a Hadoop-based ensemble of random forests trained over N-grams, and the DeepDeath, a deep classifier based on the recurrent neural network (RNN). We apply both classes to the mortality data provided by the National Center for Health Statistics and show that while both perform significantly better than the random classifier, the deep model that utilizes long short-term memory networks (LSTMs), surpasses the N-gram based models and is capable of learning the temporal aspect of the data without a need for building ad-hoc, expert-driven features.

The hypertension of hemophilia is associated with vascular remodeling in the joint

OBJECTIVE

Hemophilic arthropathy is associated with pronounced vascular joint remodeling. Also, compared to the general population, PWH have a higher prevalence of hypertension not explained by usual risk factors. As vascular remodeling in various vascular beds is a hallmark of hypertension, we hypothesized that vascular joint remodeling is associated with elevated blood pressures and hypertension.

METHODS

Elbows, knees, and ankles of 28 adult PWH were evaluated for vascular abnormalities with MSKUS/PD, as well as for radiographic and clinical status and pain. Logistic and linear regression models were fitted to examine associations between hypertension, blood pressure, and PD score.

RESULTS

The extent of vascular abnormalities was associated with hypertension and blood pressures. Hypertensive patients had a higher PD score compared to nonhypertensive patients, and the risk of hypertension increased steeply with PD score. SBP was also strongly associated with PD score, while DBP was only weakly associated.

CONCLUSIONS

Vascular remodeling in hemophilic joints is associated with hypertension and elevated blood pressures. As hypertension is a grave risk factor for intracranial hemorrhage, a prominent cause of mortality in hemophilia patients, future studies are needed to address the causal pathways between vascular joint remodeling and blood pressure.

Evaluation of Heart Function in Patients With Hemophilia

There are conflicting reports about the protective effect of hemophilia on the occurrence of ischemic heart disease. This study focuses on evaluation of heart function in patients with hemophilia. Cross-sectional, case–control study was done on all patients with hemophilia A or B who came to hemophilia center, and data were compared to controls. The data were collected from their charts, and heart function was evaluated by 2-dimensional, Doppler and pulse tissue Doppler. The serum troponin I level was measured in all patients as a marker of myocardial damage. Fifty patients with hemophilia took part in this study. All of them were male with mean age 29.1 years. Systolic blood pressure (mean = 121.52 ± 11 vs 115.61 ± 9.81, P = .038) and diastolic (mean = 81.94 ± 4.51 vs 75.21 ± 3.95, P = .042) blood pressure were higher in the patients. Five (10%) patients had systolic hypertension and 7 (14%) patients had diastolic hypertension. The M-mode echocardiography results showed that interventricular septum in diastole in patients with hemophilia (mean 1.143 ± 0.29) was significantly thicker than the control group (mean 0.828 ± 0.22, P < .001). Tissue Doppler echocardiography showed that late diastolic velocity of septum (Aa; P = .030), systolic velocity (S) of lateral mitral valve ( P = .006), late diastolic velocity of lateral mitral (Aa) annulus ( P = .038), and late velocity of (Aa) tricuspid ( P = .004) had significant difference compared with the control group ( P < .05). Troponin enzyme level was < 0.1 in all patients. Patients with hemophilia had higher blood pressure and more hypertension. Echocardiographic study of patients with hemophilia showed some increase in septal thickness and changes in diastolic dysfunction

Ledipasvir-sofosbuvir and sofosbuvir plus ribavirin in patients with chronic hepatitis C and bleeding disorders

INTRODUCTION

Chronic hepatitis C virus (HCV) infection is prevalent among patients with inherited bleeding disorders and is a leading cause of mortality in those with haemophilia.

AIM

We evaluated the efficacy and safety of ledipasvir-sofosbuvir and sofosbuvir plus ribavirin in patients with chronic HCV genotype 1-4 infection and an inherited bleeding disorder.

METHODS

Ledipasvir-sofosbuvir was administered for 12 weeks to patients with genotype 1 or 4 infection and for 12 or 24 weeks to treatment-experienced cirrhotic patients with genotype 1 infection. Patients with genotype 2 and 3 infection received sofosbuvir plus ribavirin for 12 and 24 weeks respectively.

RESULTS

The majority of the 120 treated patients had a severe bleeding disorder (55%); overall, 65% of patients had haemophilia A and 26% of patients had haemophilia B; 22% were HIV coinfected. Sustained virologic response at 12 weeks posttreatment was 99% (98/99) in patients with genotype 1 or 4 infection; 100% (5/5) in treatment-experienced cirrhotic patients with genotype 1 infection; 100% (10/10) in patients with genotype 2 infection; and 83% (5/6) in patients with genotype 3 infection. There were no treatment discontinuations due to adverse events (AEs). The most frequent non-bleeding AEs were fatigue, headache, diarrhoea, nausea and insomnia. Bleeding AEs occurred in 22 patients, of which all but one were considered unrelated to treatment.

CONCLUSION

Treatment with ledipasvir-sofosbuvir for patients with HCV genotype 1 or 4 infection or sofosbuvir plus ribavirin for patients with genotype 2 or 3 infection was highly effective and well tolerated among those with inherited bleeding disorders.

The Hypertension of Hemophilia Is Not Explained by the Usual Cardiovascular Risk Factors: Results of a Cohort Study

Background. The etiology of the high prevalence of hypertension among patients with hemophilia (PWH) remains unknown. Methods. We compared 469 PWH in the United States with males from the National Health and Nutrition Examination Survey (NHANES) to determine whether differences in cardiovascular risk factors can account for the hypertension in hemophilia. Results. Median systolic and diastolic BP were higher in PWH than NHANES (P < 0.001) for subjects not taking antihypertensives. Those taking antihypertensives showed similar differences. Differences in both systolic and diastolic BP were especially marked among adults <30 years old. Differences between PWH and NHANES persisted after adjusting for age and risk factors (body mass index, renal function, cholesterol, smoking, diabetes, Hepatitis C, and race). Conclusions. Systolic and diastolic BP are higher in PWH than in the general male population and especially among PWH < 30 years old. The usual cardiovascular risk factors do not account for the etiology of the higher prevalence of hypertension in hemophilia. New investigations into the missing link between hemophilia and hypertension should include age of onset of hypertension and hemophilia-specific morbidities such as the role of inflammatory joint disease.

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.

Long-term follow up of HIV-1-infected Korean haemophiliacs, after infection from a common source of virus

In the early 1990s, 20 haemophiliacs (HPs) were infected with a common source of HIV-1 viruses through the contaminated clotting factor IX. The aim of this study is to review 20 HPs infected with a common source of virus. The enrolled patients have been consecutively treated with Korean red ginseng (KRG), zidovudine (ZDV) or two-drug therapy and highly active antiretroviral therapy (HAART). We determined full-length pol gene over 20 years and human leukocyte antigen (HLA) class I with peripheral blood mononuclear cells and reviewed medical records. Eighteen HPs experienced various opportunistic infections or clinical manifestations. There were significant inverse correlations between the HLA prognostic score and the annual decrease in CD4+ T-cell counts prior to HAART (AD) (P < 0.05) and the amount of KRG and the AD (P < 0.01). From 1998, the HPs had been treated with HAART. Each of the two patients died without and with HAART regimen respectively. At present, 16 HPs have been alive with HAART. Among the 16 HPs, 12 and 4 are on HAART-plus-KRG and HAART only respectively. Eleven HPs including 2 HPs with G-to-A hypermutations had revealed resistance mutations. Ten and two HPs have shown poor adherence and incomplete viral suppres-sion on HAART respectively. Virological failure based on WHO guidelines was not observed on KRG-plus-HAART. Two HPs revealed additional resistance mutations against two classes on KRG-plus-HAART. As a nationwide study, we first report overall features on clinical course of Korean haemophiliacs. Further education on the importance of drug adherence is needed.

Challenges in treating elderly patients with haemophilia: a focus on cardiology

Seventy years ago, the average life expectancy for patients with severe haemophilia A was less than 17 years. Today, due to the availability of safe and effective clotting factor concentrates, life expectancy is nearly normal, at least in patients without viral infections. More individuals are living into their 70s and 80s, acquiring a range of diseases that are common in elderly persons. One of the most important challenges includes the treatment of comorbidities, especially cardiovascular diseases. Although most evidence suggests that haemophilia, at least the severe manifestation, partially protects against myocardial infarction, stroke and venous thromboembolism, typical cardiovascular risk factors can still be present despite the clotting defect. Patients with haemophilia are equally or even more prone to obesity, hypertension, diabetes, and dyslipidaemia, and this is especially true for HIV-infected individuals using highly active antiretroviral therapy. The management of elderly haemophilia patients with cardiovascular comorbidities is hampered by a lack of evidence-based guidelines. Nevertheless, experience in treating cardiovascular disease is growing amongst the haemophilia community, and several authors have published their own recommendations for managing a variety of commonly encountered cardiovascular scenarios in haemophilia patients. Basic recommendations exist for risk-factor management, the adaptation of factor replacement therapy in the at-risk elderly, management of coronary revascularization, the management of acute coronary syndrome and atrial fibrillation. This review outlines our current knowledge about cardiovascular risk in elderly haemophilia patients, recommendations for clinical decision making, and our own experiences of managing individuals with coronary heart disease and atrial fibrillation.

Innovative approach for improved rFVIII concentrate

The development of a new recombinant factor VIII was designed and implemented to answer a number of unmet needs of patients affected by hemophilia A. Turoctocog alfa is bioengineered in a specific Chinese hamster ovary clone to present translational and posttranslational characteristics (sulphation, glycosylation) biosimilar to natural circulating forms of FVIII, with the aim to devoid any minimal change which may impact immunogenicity and antigenicity of recombinant protein. Both producer cell line and media are maintained free of any animal or human plasma derivative. Downstream processes of purification are performed by five steps (immunoaffinity chromatography, ion-exchange chromatography, virus inactivation by means of solvent-detergent treatment and nanofiltration, and to end with gel filtration), to provide the best possible margin of safety from known and unknown infectious agents. Large clinical trials seem to confirm the expectations placed in Turoctocog alfa in terms of high quality and safety of recombinant FVIII toward the goal of overcoming actual and future challenges of hemophilia therapy.

Prevalence and risk factors for hypertension in hemophilia

Hypertension (HTN) is a major risk factor for intracranial hemorrhage. We, therefore, investigated the prevalence, treatment, and control of HTN in adult patients with hemophilia (PWH). PWH≥18 years (n=458) from 3 geographically different cohorts in the United States were evaluated retrospectively for HTN and risk factors. Results were compared with the nationally representative sample provided by the contemporary National Health and Nutrition Examination Survey (NHANES). PWH had a significantly higher prevalence of HTN compared with NHANES. Overall, the prevalence of HTN was 49.1% in PWH compared with 31.7% in NHANES. At ages 18 to 44, 45 to 64, 65 to 74, and ≥75 years, the prevalence of HTN for PWH was 31.8%, 72.6%, 89.7%, and 100.0% compared with 12.5%, 41.2%, 64.1%, and 71.7% in NHANES, respectively. Of treated hypertensive PWH, only 27.1% were controlled, compared with 47.7% in NHANES (all P<0.05). Age, body mass index, diabetes mellitus, and renal function were independently associated with HTN. Among patients with moderate or severe hemophilia there was a trend (≈1.5-fold) for higher odds of having HTN compared with patients with mild hemophilia. On the basis of these results, new care models for adult PWH and further studies for the causes of HTN in hemophilia are recommended.

The role of natural VWF/FVIII complex concentrates in contemporary haemophilia care: a guideline for the next decade

Current treatment for haemophilia provides excellent efficacy and safety albeit with a number of unresolved issues. The development of inhibitors following treatment with factor VIII (FVIII) is the most challenging complication of haemophilia and bears the highest economic burden for a chronic disease. Moreover, prophylactic therapy for haemophilia requires repeated infusions of FVIII, frequently as often as two or three times weekly, which can impact greatly on patients' daily lives. As considerable scope remains for further advancements in the management of this condition, the primary focus of this paper relates to issues regarding current treatment and strategies in place to resolve the various issues. For countries approaching access to replacement therapy, it is important to know whether or not plasma-derived and recombinant products are associated with different risks of inhibitor development in previously untreated patients with severe haemophilia. The ongoing international SIPPET study is expected to provide an answer to this clinical dilemma. Methods under investigation to prolong the half-life of factor concentrates offer new hope to reduce the burden of prophylaxis for patients with haemophilia, with early results suggesting greater benefits with FIX.

The aging patient with hemophilia

The prospects for many boys born with hemophilia today include a normal life expectancy and minimal to no joint disease. However, despite the availability of safe replacement clotting factor concentrates and effective antiviral treatment, the aging patient with hemophilia today faces many challenges. These include management of their hemophilia as well as the same age-related health issues as experienced in the general population. While increasing, data on the prevalence of comorbidities and their management in the hemophilia population remain limited. This review will focus on issues related to management of hemophilia and complications of cardiovascular, musculoskeletal, hepatic, and renal disease. Available research is summarized and potential approaches to management are discussed.

A case-control study reveals immunoregulatory gene haplotypes that influence inhibitor risk in severe haemophilia A

Several genes that modify risk of factor VIII (FVIII) inhibitors in haemophilia A patients have been identified. Aside from the underlying mutations that cause haemophilia A, inhibitor risk appears to be modified by polymorphisms in various cytokines and immunomodulators including IL10, TNFα and CTLA4. HLA haplotypes have not been strong determinants of inhibitor risk. We sought to confirm previous observations on FVIII inhibitor risk-modifying genes and to test new candidate genes encoding various otherTH1/TH2 cytokines. We also sought to determine whether normal FVIII gene polymorphisms affect inhibitor risk in caucasians. We studied 915 caucasian, severe haemophilia A patients (282 inhibitor cases and 633 non-inhibitor controls). Genes were analysed using 368 tagging single nucleotide polymorphisms starting 20 kb 5' and ending 10 kb 3' of each gene's coding sequence; four other polymorphisms (factor V Leiden & prothrombin 20210 polymorphisms and two in HFE) were also evaluated. Haplotypes that increased inhibitor risk were found in IL10 (OR = 1.33, P = 0.04), IL12 (OR = 1.31, P = 0.04) and IL1α (OR = 2.16, P = 0.034). Protective haplotypes were seen in IL2 (OR =  .69, P = 0.008) and IL1β (OR = 0.75, P = 0.02). One rare haplotype in the FVIII gene increased the risk of inhibitor development by nearly fourfold (OR = 3.8, P = 0.004). We replicate previous findings for IL10; identify new associations with IL1, IL2 and IL12; and identify a rare FVIII haplotype in caucasians that is associated with increased inhibitor risk.

The Aging Patient with Hemophilia: Complications, Comorbidities, and Management Issues

Improvements in hemophilia care and antiviral treatments have resulted in increases in median life expectancy for persons with congenital hemophilia A and B. Currently, 2% of hemophilia A and B patients surveyed in US comprehensive hemophilia treatment centers are 65 years of age or older and 15% are 45 years or older. Many of the complications of hemophilia, including intracranial hemorrhage, joint disease, and inhibitor development, increase with increasing age. Hepatocellular carcinoma and end-stage liver disease are increasing in the older hemophilia population due to infection with hepatitis C (HCV) and HCV/HIV coinfection. Older hemophilia patients also now face the same medical conditions associated with aging in the general population, including cardiovascular disease and cancer. Complex hemostatic management, sometimes in conjunction with antithrombotic management, with extensive cross-specialty clinical and laboratory coordination may be required for the care of the older hemophilia patient. Because elderly hemophilia patients currently represent a small portion of the overall hemophilia population, there is little in the way of clinical data to guide recommendations. Registry databases and cooperative group studies are needed for the development of evidence-based guidelines for the older hemophilia population, which is anticipated to expand in the future.

Mortality and causes of death in Italian persons with haemophilia, 1990-2007

Although a number of studies have analysed so far the causes of death and the life expectancy in haemophilic populations, no investigations have been conducted among Italian haemophilia centres. Thus, the aim of this study was to investigate mortality, causes of deaths, life expectancy and co-morbidities in Italian persons with haemophilia (PWH). Data pertaining to a total of 443 PWH who died between 1980 and 2007 were retrospectively collected in the 30 centres who are members of the Italian Association of Haemophilia Centres that chose to participate. The mortality rate ratio standardized to the male Italian population (SMR) was reduced during the periods 1990-1999 and 2000-2007 such that during the latter, death rate overlapped that of the general population (SMR 1990-1999: 1.98 95% CI 1.54-2.51; SMR 2000-2007: 1.08 95% CI 0.83-1.40). Similarly, life expectancy in the whole haemophilic population increased in the same period (71.2 years in 2000-2007 vs. 64.0 in 1990-1999), approaching that of the general male population. While human immunodeficiency virus infection was the main cause of death (45%), 13% of deaths were caused by hepatitis C-associated complications. The results of this retrospective study show that in Italian PWH improvements in the quality of treatment and global medical care provided by specialized haemophilia centres resulted in a significantly increased life expectancy.

Aging with hemophilia: implications for social work practice

Individuals with hemophilia and other congenital bleeding disorders are surviving beyond any life expectancy previously predicted and now face conditions associated with "normal" aging. Hemophilia along with co-morbid conditions of HIV and Hepatitis C complicate treatment for heart disease, cancer, kidney disease, and other age-related diseases. Lack of understanding of the condition, its treatment, and its costs hampers care, particularly when patients are treated outside of specialty clinics. This article provides an overview of bleeding disorders with a special focus on aging considerations. The role of social work in specialized hemophilia treatment centers is described and suggestions made to other social workers who may encounter this population in their practice. Finally, the need for policy and advocacy strategies is also addressed.

Co-morbidities and quality of life in elderly persons with haemophilia

The life expectancy and quality of life of persons with haemophilia has dramatically increased since the 1970s, with the exception of the increased rate of deaths observed during the 1980s and the 1990s due to blood-borne viral infections. Improvements of factor replacement therapy, treatment of infectious diseases and comprehensive health care provided by specialised haemophilia centres are the main determinants of the increasing age of the haemophilia population. As a consequence, a growing number of these patients develop age-related co-morbidities, such as cardiovascular disease and cancer. The care of these previously rare conditions is a new challenge for caregivers in haemophilia centres. This review focuses on co-morbidities in the ageing haemophilia patients, their impact on quality of life and their complex management.

Challenges and controversies in haemophilia care in adulthood

Overall life expectancy and quality of life among persons with haemophilia have increased in recent years, primarily because of the advances in factor replacement therapy and better treatment of infectious diseases. Older haemophilic patients now face aging co-morbidities that are common in the general male population, such as cardiovascular or metabolic diseases, prostate hypertrophy and hepatic, prostate and other cancers. The prevalence of cardiovascular disease and incidence of vascular events among older haemophilic patients can be expected to increase and haemophilic patients may become prone to some cardiovascular risk factors, warranting preventative measures. The treatment of long-term complications of hepatitis C virus infection such as liver cirrhosis and hepatic cancer can be expected to be required in a large portion of the older haemophilia population for some years to come. Appropriate antiviral treatment and close monitoring for possible disease advancement will constitute an important part of routine medical care, and special considerations may be appropriate in conjunction with invasive procedures, chemo- or radiotherapy. At the moment, hard data on which to base the management of these conditions are largely lacking, but can be expected to increase dramatically in the coming decades. In the meantime, the ageing population of haemophilia patients should be offered the same comprehensive health care offered to the general population, which may require a restructuring of health care delivery.

Antihemophilic factor (recombinant) plasma/albumin-free method for the management and prevention of bleeding episodes in patients with hemophilia A

Hemophilia is a rare genetic bleeding disorder that, if not adequately controlled, is associated with life-threatening bleeding events and serious and costly complications, primarily from joint damage. The advent of effective clotting factor replacement therapy for patients with hemophilia is considered one of the foremost medical advances of the 20th century. The last 3 decades of experience in hemophilia care have witnessed the effectiveness of the care of patients with hemophilia within specialized comprehensive care centers, advances in factor replacement therapies, the benefits of prophylaxis over on-demand replacement therapy, and the role of aggressive management of joint disease to prevent dysfunction. Ongoing challenges, including the management of inhibitors to factor therapies and the consequences of thousands of patients with hemophilia becoming infected with human immunodeficiency virus and hepatitis C virus in the 1980s from contaminated plasma-derived factor concentrates, have highlighted the need for vigilance with respect to clotting factor product safety, access to care, and a full complement of choice of factor replacement therapies. Advate^® (antihemophilic factor [recombinant] plasma/albumin-free method [rAHF-PFM]) is the first recombinant factor VIII therapy manufactured without human or animal protein additives to eliminate the risk of pathogen transmission that could be carried by these additives. Preclinical studies established bioequivalence with recombinant antihemophilic factor (Recombinate^®), a product with 16 years of clinical experience. Currently licensed in 44 countries worldwide, rAHF-PFM has over 7 years of clinical research within 5 global studies supporting its safety and efficacy in the treatment of patients with hemophilia A.

Potency and mass of factor VIII in FVIII products

Several factor (F) VIII products of different origin and structure are being used for haemophilia A treatment worldwide. The assessment of FVIII concentration in these products is done using activity assays, which are dependent upon the assay and its modifications. To evaluate FVIII products for potency and for FVIII concentration and specific activity, three activity-based assays [activated partial thromboplastin time (APTT), intrinsic FXase and synthetic coagulation proteome] and two immunoassays (ELISA and western blotting) were used in this study with albumin-free full-length recombinant (r) FVIII as a standard. In all activity assays, products A and B (both contain full-length rFVIII) at 1 U mL(-1) showed potency similar to that of the 0.7 nm (1 U mL(-1)) rFVIII standard. Product E (contains truncated rFVIII) was less potent in the APTT (83% of standard) and product C (contains plasma FVIII) was less potent in FXase assays (66%). The ELISA immunoassay revealed that the specific activity of FVIII proteins in products A-C and E varied over a wide range (3900-13 200 U mg(-1)) and was higher for most lots when compared with the standard (5000 U mg(-1)), whereas the specific activity of product D (contains plasma FVIII) was lower than expected (3200-4800 U mg(-1)). (i) FVIII potency estimated in different assays gives dissimilar results; (ii) the specific activity of FVIII in various FVIII products is different and inconsistent. Thus, the administration of an equal FVIII potency in units means the administration of different amounts of FVIII protein, which may partly explain apparent discrepancies in product performance.

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.

Should hemophilia treaters switch to albumin-free recombinant factor VIII concentrates

PURPOSE OF REVIEW

To discuss the advantages and disadvantages of the albumin-free recombinant factor VIII concentrates in the treatment of hemophilia A.

RECENT FINDINGS

The third-generation recombinant factor VIII product Advate has been found to be safe and effective in treating bleeding associated with hemophilia A.

SUMMARY

Multiple issues must be considered when selecting a factor VIII concentrate for patients with hemophilia A including efficacy, availability, risk of transmission of infectious agents, risk of inhibitor development and cost. Third-generation recombinant factor VIII concentrates have been shown to be safe and effective. A theoretical improvement in risk of infectious agent transmission has been achieved by production of the products without human or animal plasma proteins. Controversy exists, however, with regard to a higher risk of inhibitor development with recombinant products. The higher cost of Advate can also potentially play a role in product choice. Overall every patient and their family must be presented with the advantages and disadvantages of all factor VIII concentrates, and be allowed to make an informed decision about which product to use for treatment.

Knowledge, attitudes, and behaviors of youths in the US hemophilia population: results of a national survey

OBJECTIVES

The National Hemophilia Foundation and the Centers for Disease Control and Prevention conducted a national survey focusing on knowledge about, attitudes toward, and behaviors associated with key prevention activities among youths with hemophilia and used the data gathered to design a health promotion campaign.

METHODS

A national, random sample of 459 patients was drawn from 20 hemophilia treatment centers and 8 hemophilia associations; 110 (24%) of the respondents were young people. A telephone questionnaire was used to measure knowledge, behaviors, and barriers to prevention.

RESULTS

Thirty-six percent of the youth respondents believed that joint disease cannot be prevented; 60% managed hemophilia by avoiding physical activity. Only 31% of the respondents treated bleeding episodes within 1 hour. Although hepatitis was a clear threat to this hemophilic cohort, 78% did now know transmission routes for hepatitis C, and 67% did not know transmission routes for hepatitis B.

CONCLUSIONS

Young people with chronic disorders need help understanding that they can prevent complications. We identified key messages for a hemophilia prevention campaign, including exercising to ensure healthy joints and treating bleeding episodes early and adequately.

Infectious disease in the blood supply and the public health response

The consistent improvements in hemophilia care seen in the years 1960 to 1980 halted when human immunodeficiency virus (HIV) appeared in the blood supply. In the early 1980s, before HIV virulence was fully understood, a complacent blood therapy industry and its regulators waffled on an appropriate response. As a result, the period between the appearance of HIV and its effective elimination from the blood supply was lengthy and many recipients of blood therapies became infected, with devastating impact on their quality of life, quality of care, and longevity. As the decade wore on, even as they began to better understand the threat, industry and public health officials continued to stall, in part because development of interventions was costly and cumbersome. In order to protect the safety of the blood supply and blood-derived therapies, it must be recognized that new pathogens will continue to emerge. Agencies' and companies' decision-making processes in this regard must therefore be proactive rather than reactive, and should preferably implement a formalized risk-management approach. The ongoing safety of blood therapies and the blood supply will also depend on continued vigilance and research. Finally, the hemophilia community must be allowed to play an active and educated role in their own care.

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.

Clinical uses of plasma and plasma fractions: plasma-derived products for hemophilias A and B, and for von Willebrand disease

The use of plasma-derived factor products to treat hemophilia A, hemophilia B, and von Willebrand disease (vWD) has changed since the start of the human immunodeficiency virus (HIV) epidemic. The use of plasma-derived factor concentrates for hemophilias A and B has decreased in developed countries because of the availability of recombinant products. However, in developing countries, which encompass most of the world's hemophilia community, plasma-product-based therapy remains the backbone of treatment because of economic constraints. Viral attenuation strategies have resulted in a much safer product profile. vWD product selection is less complicated than for hemophilas A and B because plasma-derived products are the only choice for patients who are unresponsive or who cannot receive pharmacologic therapy. As the majority of patients in the world with hemophilias A, B and vWD are treated with plasma-derived clotting factors, the need for these safe and efficacious therapies will continue in the future. This chapter discusses safety strategies for plasma-derived clotting factor, its availability, economics, efficacy, and inhibitor formation.

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.

Survival analysis of patients with haemophilia at the International Haemophilia Training Centre, Bangkok, Thailand

Haemophiliac treatment in less developed countries is limited to locally prepared fresh frozen plasma, cryoprecipitate, cryo-removed plasma and lyophilized products as replacement therapy. Factor concentrate is seldom used because of the high price. The present study reports the survival analysis of 164 patients comprising 138 haemophilia A and 26 haemophilia B cases from 134 families registered at the International Haemophilia Training Centre-Bangkok, Faculty of Medicine, Ramathibodi Hospital, Mahidol University from 1971 to 2000. The duration of follow-up ranged from 1 to 27 years and 8 months with a median of 9 years and 1 month. They received treatment on demand of bleedings, and 85 patients received additional home treatment for early bleedings. The proportion of death was 15.2%. The Kaplan-Meier survival curves revealed the median (95% CI) survival time of patients with severe and moderate degrees of 35 years and 6 months (21.4-49.7), and 38 years and 1 month (28.8-47.3), respectively. To compare the progressive achievement of haemophilia care services, the treatment period was divided into three decades: 1971-1980, 1981-1990 and 1991-2000. The patients with unaided proper walking increased from 62.8% in the first decade to 84.5% in the third decade. However, one-third of the patients developed one to four chronic haemarthrosis determined by clinical evaluation, especially patients with severe degree. Moreover, the estimated probability of a survival time beyond 13 years of age among patients with severe degree increased from 0.85 in the first decade to 0.94 and 1 in the second and third decades, respectively. Thus, established haemophilia care, even with limited resources, has significantly decreased the risk of death and increased the survival time among patients with haemophilia.

Factors associated with reporting multiple causes of death

Background

There is analytical potential for multiple cause of death data collected from death certificates. This study examines relationships of multiple causes of death as a function of factors available on the death certificate (demographics of decedent, place of death, type of certifier, disposal method, whether an autopsy was performed, and year of death).

Methods

Data from 326,332 Minnesota death certificates from 1990–1998 are examined. Underlying and non-underlying causes of death are examined (based on record axis codes) as well as demographic and death-related covariates. Associations between covariates and prevalence of multiple causes of death and conditional probability of underlying compared to non-underlying causes of death are examined. The occurrence of ischemic heart disease or diabetes as underlying causes are specifically examined.

Results

Both the probability of multiple causes of death and the proportion of underlying cause compared to non-underlying cause of death are associated with demographic characteristics of the deceased and other non-medical conditions related to filing death certificate such as place of death.

Conclusions

Multiple cause of death data provide a potentially useful way of looking for inaccuracies in reporting of causes of death. Differences across demographics in the proportion of time a cause is selected as underlying compared to non-underlying exist and can potentially provide useful information about the overall impact of causes of death in different populations.

Renal disease among males with haemophilia

Haematuria is common among persons with haemophilia (PWH), but its long-term effects on the kidney and renal function are not well defined. In addition, infection with human immunodeficiency virus (HIV) or hepatitis C, or exposure to nephrotoxic agents as therapy for these infections may place PWH at increased risk for renal disease. To examine factors associated with chronic renal disease (CRD) and acute renal disease (ARD) in PWH, we analysed data collected from the medical records of 3422 males with haemophilia living in six US states from 1993 to 1998. Renal disease cases were ascertained from among 2075 persons who were hospitalized at least once over the 6-year period. Of these, 60 (2.9%) were diagnosed during one or more hospitalizations with either ARD (29/60) or CRD (31/60). In multivariate analyses, we examined associations between renal disease and demographic and clinical factors including age, race, haemophilia type and severity, hypertension, diabetes, history of recent renal bleeds, presence of an inhibitor, and infection with hepatitis C or HIV. HIV infection and hypertension were strongly associated with both ARD and CRD. PWH who had ARD were also more likely to have an inhibitor than those without this diagnosis. PWH who had CRD were more likely to be older and non-white and to have had a recent admission for a kidney bleed than those without diagnosed CRD. In summary, we found that HIV infection and haemophilia-related factors including inhibitors and kidney bleeds were associated with renal disease in a cohort of males with haemophilia.

Influence of factor VIIa and phospholipids on coagulation in "acquired" hemophilia

OBJECTIVE

This study was performed to evaluate the influences of phospholipids and recombinant factor VIIa (rFVIIa) on thrombin generation and clot formation in "acquired" hemophilia B.

METHODS AND RESULTS

A synthetic mixture corresponding to hemophilia A (SHA) and "acquired" hemophilia B blood (AHBB) manufactured in vitro by an anti-FIX antibody were used in this study. With 10 pmol/L tissue factor (TF), 10 nmol/L rFVIIa, and saturating phospholipid, established thrombin generation in SHA was similar to that observed in the presence of factor VIII and rFVIIa at physiological concentrations. At lower phospholipid concentrations, thrombin generation was delayed and reduced. With 5 pmol/L TF, contact pathway-inhibited AHBB clotted later than normal blood and showed reduced clot stability and thrombin generation. These parameters of effectiveness were increased by the addition of phospholipids to AHBB, which restored clot stability and increased thrombin generation. No correction of clot formation or thrombin generation was observed when rFVIIa and phospholipids were added to AHBB in the absence of TF.

CONCLUSIONS

The influence of rFVIIa is dependent on TF, and phospholipids substantially increase the hemostatic (or thrombotic) potential of rFVIIa/TF.