Reported prevalence of von Willebrand disease worldwide in relation to income classification

INTRODUCTION

The diagnosis of von Willebrand disease (VWD) is complex and challenging, especially when diagnostic resources are limited. This results in a lack of consistency in identifying and reporting the number of people with VWD and variations in the VWD prevalence worldwide.

AIM

To analyze the reported prevalence of VWD worldwide in relation to income classification.

METHODS

Data on the VWD prevalence from the World Federation of Hemophilia Annual Global Survey, national registries of Australia, Canada, and the United Kingdom, and the literature were analysed. The income level of each country was classified according to the World Bank.

RESULTS

The mean VWD prevalence worldwide was 25.6 per million people. The VWD prevalence for high-income countries (HIC) of 60.3 per million people was significantly greater (p < .01) than upper middle (12.6), lower middle (2.5) and low (1.1) income countries. The type 3 VWD prevalence for HIC of 3.3 per million people was significantly greater (p < .01) than lower middle (1.3) and low income (0.7) countries. The reported VWD prevalence was greater among females than males.

CONCLUSION

The reported VWD prevalence varied considerably across and within income classifications. The variability of type 3 VWD prevalence was less than the VWD prevalence (all types). The variability in detection and diagnosis of type 1 VWD presents a challenge in forming a consistent prevalence value across countries and income classifications.

Evaluation of the sexual health in people living with hemophilia

BACKGROUND

Knowledge about sexual health, difficulty with sexual activity and intimacy (sexual difficulty), in people with hemophilia is little understood.

OBJECTIVES

The objectives were to determine the prevalence of sexual difficulty in people living with hemophilia (PWH) compared to people with no bleeding disorders (PWNoBD), and to determine factors associated with it.

METHODS

This was an analysis of the PROBE study. We recruited individuals who had hemophilia A or B (PWH) and PWNoBD who were 18 years old or older. We calculated proportions of participants with sexual difficulty and odds ratios (ORs) adjusted for sex and age with 95% confidence intervals.

RESULTS

There were 2007 PWH and 1972 PWNoBD. Mean (standard deviation) age was 41 (15) years in PWH and 42 (13) years in PWNoBD. Sexual difficulty was reported in 302 (15.1%) PWH and 79 (4.0%) PWNoBD. The odds of sexual difficulty were significantly higher in PWH (OR 3.82, 95% CI 2.85, 5.11). Among PWH, older age, experiencing acute or chronic pain in the past 12 months, bleeds within the past two weeks, ≥3 spontaneous joint bleeds (past six months), limitation of range of motion of any joints, and any life- or limb-threatening bleeds in the past 12 months were associated with sexual difficulty.

CONCLUSIONS

Sexual difficulty is more prevalent in people living with hemophilia and associated with markers of disease severity. Sexual health issues should be incorporated in comprehensive hemophilia care, future research, and hemophilia related health policy.

Converting factor and nonfactor usage into a single metric to facilitate benchmarking the resources consumed for haemophilia care across jurisdictions and over time

INTRODUCTION

The World Federation of Hemophilia started measuring factor utilization at the country level as IU/capita (International Units of factor concentrates used per country population) in 2001 for its Annual Global Survey. IU/capita have been used to benchmark a country's usage over time and for advocacy. The introduction of a common metric usage spanning across standard half-life (SHL), and extended half-life (EHL) clotting factor concentrates (CFCs) and emicizumab would be a valuable simplification for national healthcare policymaking and industrial production planning.

AIM

Develop and examine a method of converting IU of SHL or EHL, and milligrams of emicizumab into a single metric.

METHODS

We developed conversion factors from manufacturer's recommended dose for prophylaxis with SHL, EHL, and emicizumab as reported on the licensing information for the United States and Europe. We validate the accuracy of these conversion factors against real-world usage data.

RESULTS

The prescribing information in the United States and Europe is marginally different. The SHL/EHL conversion factors are higher when calculated based on the prescribing information than on real-world studies, which are considered more representative of clinical practice. The best estimate of the SHL/EHL conversion factors for FVIII and FIX were 1.04 and 1.87. The conversion factor for emicizumab to SHL is 70 IU/mg.

CONCLUSION

We have generated robust estimates of conversion factors for currently used treatment options for prophylaxis in haemophilia. Usage of a single, harmonized metric will facilitate benchmarking across different countries or longitudinally irrespective of the case-mix of treatment options.

Modelling future usage and cost of factor and emicizumab to treat haemophilia A for the US Western States Region IX haemophilia treatment centres

INTRODUCTION

Increased usage of emicizumab in the United States will affect standard half-life (SHL) and extended half-life (EHL) products usage and cost.

AIM

To model the usage and cost of SHL and EHL products, and emicizumab to treat haemophilia A (HA) in the 13 Western States Region IX haemophilia treatment centres (HTCs.) (California, Nevada, Hawaii and Guam).

METHODS

We modelled product usage and cost using decision analysis methods.

VARIABLES

epidemiology/demographics, treatment and product cost. Data were from the US Western States Region IX, US Centers for Disease Control and Prevention, American Thrombosis and Hemostasis Network and the literature.

RESULTS

Prior to EHL products and emicizumab, the usage of SHL products was ~300 million international units (IUs) or 6.8 IUs/capita and a cost of $430 million. With the uptake of EHL and emicizumab, the 2025 estimated usage of factor (SHL and EHL) was 270 million IUs (5.4 IU per capita) and 1,993 grams (40 micrograms/capita) for emicizumab and a cost of $532 million. As the number of HA patients in the region increases by 59%, factor usage increases by 20%, emicizumab usage increases by 26%, and cost increases to $650 million.

CONCLUSION

The entrance of emicizumab into the market may radically change the use of SHL and EHL products. Our model suggests that emicizumab use will likely increase total product costs. While our estimates are most useful for the United States, the effect of emicizumab on factor use will likely be similar in other parts of the world.

Non-severe haemophilia: Is it benign? - Insights from the PROBE study

INTRODUCTION

There are limited data on the impact of haemophilia on health status and health-related quality of life (HRQL) in people with non-severe (mild and moderate) haemophilia.

AIM

To evaluate the health status of people living with mild or moderate haemophilia.

METHODS

Data on respondents with no bleeding disorder (NoBD), mild and moderate haemophilia patients were drawn from the PROBE study. Respondents were enrolled using network patient organizations. This analysis was performed as a cross-sectional study. Primary outcomes were reported bleeding, acute and chronic pain, activities of daily living and HRQL.

RESULTS

A total of 862 respondents with NoBD (n = 173), mild (n = 102) and moderate (n = 134) haemophilia were eligible, with a median age of 33, 42 and 43, respectively. In relation to haemophilia-related sequalae, 53% of male and 29% of female patients with mild and 83% of males with moderate haemophilia had more than 2-3 bleeds in the last 12 months. Reporting of acute and chronic pain is less in those with NoBD compared to the mild and moderate cohorts for both genders. Multivariate analysis demonstrates significant reductions in quality of life using VAS, EQ-5D-5L and PROBE for males with mild and moderate haemophilia (P ≤ .001) with only PROBE indicating a significant reduction for females with mild (P = .002).

CONCLUSION

People affected by mild or moderate haemophilia report a significant HRQL impact due to haemophilia-related bleeding. Future research is needed to identify the optimal care management of patients with mild and moderate haemophilia.

Establishing the Prevalence and Prevalence at Birth of Hemophilia in Males: A Meta-analytic Approach Using National Registries

BACKGROUND

The large observed variability in hemophilia prevalence prevents robust estimation of burden of disease.

OBJECTIVE

To estimate the prevalence and prevalence at birth of hemophilia and the associated life expectancy disadvantage.

DESIGN

Random-effects meta-analysis of registry data.

SETTING

Australia, Canada, France, Italy, New Zealand, and the United Kingdom.

PARTICIPANTS

Male patients with hemophilia A or B.

MEASUREMENTS

Prevalence of hemophilia as a proportion of cases to the male population, prevalence of hemophilia at birth as a proportion of cases to live male births by year of birth, life expectancy disadvantage as a 1 - ratio of prevalence to prevalence at birth, and expected number of patients worldwide based on prevalence in high-income countries and prevalence at birth.

RESULTS

Prevalence (per 100 000 males) is 17.1 cases for all severities of hemophilia A, 6.0 cases for severe hemophilia A, 3.8 cases for all severities of hemophilia B, and 1.1 cases for severe hemophilia B. Prevalence at birth (per 100 000 males) is 24.6 cases for all severities of hemophilia A, 9.5 cases for severe hemophilia A, 5.0 cases for all severities of hemophilia B, and 1.5 cases for severe hemophilia B. The life expectancy disadvantage for high-income countries is 30% for hemophilia A, 37% for severe hemophilia A, 24% for hemophilia B, and 27% for severe hemophilia B. The expected number of patients with hemophilia worldwide is 1 125 000, of whom 418 000 should have severe hemophilia.

LIMITATION

Details were insufficient to adjust for comorbid conditions and ethnicity.

CONCLUSION

The prevalence of hemophilia is higher than previously estimated. Patients with hemophilia still have a life expectancy disadvantage. Establishing prevalence at birth is a milestone toward assessing years of life lost, years of life with disability, and burden of disease.

PRIMARY FUNDING SOURCE

None.

Latent therapeutic demand model for the immunoglobulin replacement therapy of primary immune deficiency disorders in the USA

BACKGROUND AND OBJECTIVES

Our research aim is to model latent therapeutic demand (LTD) for the immunoglobulin replacement therapy (IgGRT) of primary immune deficiency disorders (PIDDs) in the USA. Given the high level of variability of IgGRT use and major differences among American and European practices in the management of patients with PIDDs, we develop a USA-specific LTD model for common variable immune deficiency (CVID), hyper IGM syndrome, severe combined immune deficiency, Wiskott-Aldrich syndrome and X-linked agammaglobulinemia (XLA).

METHODS AND MATERIALS

We use decision analysis methods to model the underlying IgGRT demand for PIDDs by assessing USA-specific epidemiology and treatment. Data for the epidemiology and treatment variables were obtained from the medical literature, USIDNET and Immune Deficiency Foundation. The uncertainty surrounding the variables was modelled using probability distributions and evaluated using Monte Carlo simulation.

RESULTS

The mean treatment dose from USIDNET and European Society for Immunodeficiencies (ESID) was significantly different for treating CVID, and the number of annual infusions from USIDNET and ESID was significantly different for treating CVID and XLA. The mean and standard deviation of LTD for all PIDDs is 105·1 ± 88·5 g per 1000 population, with CVID contributing the most to LTD.

CONCLUSION

Estimating country-specific LTD is important to ensure an adequate supply of IgGRT and an optimal treatment for patients with PIDDs and for improving national healthcare policymaking and production planning.

The Patient Reported Outcomes, Burdens and Experiences (PROBE) Project: development and evaluation of a questionnaire assessing patient reported outcomes in people with haemophilia

Background

The interest of health care agencies, private payers and policy makers for patient-reported outcomes (PRO) is continuously increasing. There is a substantial need to improve capacity to collect and interpret relevant PRO data to support implementation of patient-centered research and optimal care in haemophilia. The Patient Reported Outcomes, Burdens and Experiences (PROBE) Project aims to develop a patient-led research network, to develop a standardized questionnaire to gather patient-reported outcomes and to perform a feasibility study of implementing the PROBE questionnaire.

Methods

A pilot questionnaire was developed using focus group methodology. Content and face validity were assessed by a pool of persons living with haemophilia (PWH) and content experts through interactive workshops. The PROBE questionnaire was translated with the forward-backward approach. PROBE recruited national haemophilia patient non-governmental organizations (NGOs) to administer the questionnaire to people with and without haemophilia. PROBE measured the time to complete the questionnaire and gathered feedback on its content and clarity; staff time and cost required to implement the questionnaire were also collected.

Results

The PROBE questionnaire is comprised of four major sections (demographic data, general health problems, haemophilia-related health problems and health-related quality of life using EQ-5D-5L and EQ-VAS). Seventeen NGOs participated in the pilot study of the PROBE Project, recruiting 656 participants. Of these, 71% completed the questionnaire within 15 min, and all participants completed within 30 min. The median total staff and volunteer time required for the NGOs to carry out the study within their country was 9 h (range 2 to 40 h). NGO costs ranged from $22.00 to $543.00 USD per country, with printing and postage being the most commonly reported expenditures.

Conclusions

The PROBE questionnaire assesses patient-important reported outcomes in PWH and control participants, with a demonstrated short completion time. PROBE proved the feasibility to engage diverse patient communities in the structured generation of real-world outcome research at all stages.

Trial registration

Trial registration: NCT02439710.

Electronic supplementary material

The online version of this article (10.1186/s40814-018-0253-0) contains supplementary material, which is available to authorized users.

Measuring the quality of haemophilia care across different settings: a set of performance indicators derived from demographics data

BACKGROUND

Haemophilia is a rare disease for which quality of care varies around the world. We propose data-driven indicators as surrogate measures for the provision of haemophilia care across countries and over time.

MATERIALS AND METHODS

The guiding criteria for selection of possible indicators were ease of calculation and direct applicability to a wide range of countries with basic data collection capacities. General population epidemiological data and haemophilia A population data from the World Federation of Hemophilia (WFH) Annual Global Survey (AGS) for the years 2013 and 2010 in a sample of 10 countries were used for this pilot exercise.

RESULTS

Three indicators were identified: (i) the percentage difference between the observed and the expected haemophilia A incidence, which would be close to null when all of the people with haemophilia A (PWHA) theoretically expected in a country would be known and reported to the AGS; (ii) the percentage of the total number of PWHA with severe disease; and (iii) the ratio of adults to children among PWHA standardized to the ratio of adults to children for males in the general population, which would be close to one if the survival of PWHA is equal to that of the general population. Country-specific values have been calculated for the 10 countries.

CONCLUSIONS

We have identified and evaluated three promising indicators of quality of care in haemophilia. Further evaluation on a wider set of data from the AGS will be needed to confirm their value and further explore their measurement properties.

A study of reported factor VIII use around the world

The effect of replacement therapy has significantly improved the morbidity and mortality of people with haemophilia A in high income countries, a recent socio-economic development as the availability of safe concentrates has been matched by a willingness for their provision through reimbursement. In the developing world, however, this state has not been achieved, primarily because of the low visibility of haemophilia coupled with its expense, leading to inadequate treatment with its sequelae of severe pain, joint deformities, arthropathy, disabilities, and even death in childhood or early adult life. The objective of this paper was to study the reported factor VIII (FVIII) use on a country-by-country basis. Data on the reported FVIII use for 104 countries were obtained from the Marketing Research Bureau, Inc. and the World Federation of Hemophilia. The results show that FVIII use varies considerably among countries, even among the wealthiest of countries. The use of FVIII concentrate increases as economic capacity increases; in addition, consumption of FVIII has been increasing at a greater rate in high income countries. Given these trends, there probably will be a global increase in FVIII concentrates usage. Such information is critical for national healthcare agencies to determine realistic budget priorities in planning for an increased allocation of resources required to improve the treatment of patients with haemophilia A. This information is also important for pharmaceutical manufacturers to adequately plan for increased production of FVIII concentrates.

A study of variations in the reported haemophilia A prevalence around the world

The objectives of this paper were to study the reported haemophilia A prevalence (per 100 000 males) on a country-by-country basis and address the following: Does the reported prevalence of haemophilia A vary by national economies? We collected prevalence data for 106 countries from the World Federation of Hemophilia (WFH) annual global surveys and the literature. We found that the reported haemophilia A prevalence varied considerably among countries, even among the wealthiest of countries. The prevalence (per 100 000 males) for high income countries was 12.8 +/- 6.0 (mean +/- SD) whereas it was 6.6 +/- 4.8 for the rest of the world. Within a country, there was a strong trend of increasing prevalence over time--the prevalence for Canada ranged from 10.2 in 1989 to 14.2 in 2008 (R = 0.94 and P < 0.001) and for the United Kingdom it ranged from 9.3 in 1974 to 21.6 in 2006 (R = 0.94 and P < 0.001). Prevalence data reported from the WFH compared well with prevalence data from the literature. Patient registries generally provided the highest quality of prevalence data. The lack of accurate country-specific prevalence data has constrained planning efforts for the treatment and care of people with haemophilia A. With improved information, healthcare agencies can assess budgetary needs to develop better diagnostic and treatment facilities for affected patients and families and work to ensure adequate supplies of factor VIII concentrates for treatment. In addition, this information can help manufacturers plan the production of concentrates and prevent future shortages.

Modelling haemophilia epidemiology and treatment modalities to estimate the unconstrained factor VIII demand

The article presents a new method for estimating the unconstrained factor VIII (FVIII) demand based on the principles of decision analysis. Epidemiology and treatment modalities were integrated into a model for unconstrained FVIII demand. Assumptions for each variable with impact on the unconstrained FVIII demand were defined and probability estimates for these variables were obtained from the literature and medical experts. The sensitivity of the unconstrained FVIII demand to each of the variables was determined, and the variables with the greatest impact were modelled probabilistically. The probability-weighted average for the unconstrained FVIII demand model was 6.9 units per capita with a 90% uncertainty interval of 2.7-13.6 units per capita. When compared with FVIII usage in countries, only Luxembourg's use of FVIII (7.7 units per capita) exceeded the probability-weighted average for the modelled unconstrained FVIII demand. As better information becomes available, revision of model variables is easily accomplished allowing for a more accurate and dynamic forecast of demand over time. More accurate modelling of the 'true' demand longitudinally should help prevent shortages of FVIII concentrates such as those that have occurred in the past. In addition, a more accurate forecast of FVIII demand will allow national health care policy makers to better allocate financial and other resources. Sufficient and consistent supply of FVIII concentrates and appropriate financing of haemophilia care will allow the clinical benefits of more aggressive treatment regimens such as prophylaxis to be realized.

A country-by-country comparison of FVIII concentrate consumption and economic capacity for the global haemophilia community

The article presents a method to estimate the level of factor VIII (FVIII) concentrate consumption and economic capacity for each of the 110 countries considered in the study. A number of health-economic indicators were examined and purchasing power parity (PPP) gross national income (GNI) per capita had the strongest correlation with amount of FVIII concentrates sold in a country. Available data on FVIII concentrate consumption and health-economic indicators were used to calculate index values for FVIII use and economic capacity so each country can assess and compare its level of FVIII concentrate consumption with the economic resources of other countries in the global haemophilia A community. This article is of importance to policy makers, care givers and patient organizations in planning health-care resources for the treatment of haemophilia.