The number of people with hemophilia worldwide is higher than previously estimated, and patients still face a shortened life expectancy, according to an international meta-analysis of registry data.
Approximately 1.125 million people have hemophilia worldwide, compared with the previous estimate of 400,000, reported lead author Alfonso Iorio, MD, PhD, of McMaster University, Hamilton, Ont., and colleagues.
The previous estimate, from the early 2000s, was based on prevalence in the United States and the global population at the time, the investigators explained. Their report is in Annals of Internal Medicine.
They noted a lack of clarity in prior estimates concerning type and severity of hemophilia, and aimed to correct this knowledge gap with the present meta-analysis.
Prevalence was estimated using data from registries in Australia, Canada, Italy, France, the United Kingdom, and New Zealand, which are all high-income countries. Prevalence at birth was estimated using the Canadian, French, and British registries, as these are the most established databases, according to the investigators. The World Federation of Hemophilia Annual Global survey was used to estimate the total global number of patients with hemophilia, while national statistics databases were used to determine the number of males and live male births.
Of the 1.125 million cases of hemophilia worldwide, the investigators estimated that 418,000 are likely severe. Proportionally, 17.1 out of 100,000 males have hemophilia A, with 6.0 out of 100,000 males exhibiting severe hemophilia A. Hemophilia B is less common, occurring in 3.8 out of 100,000 males, with a 1.1 out of 100,000 classified as severe.
Turning to prevalence at birth, the investigators estimated that there are 24.6 cases of hemophilia A per 100,000 male births and 5.0 cases of hemophilia B per 100,000 male births.
The associated life expectancy disadvantage in high-income countries is highest for severe hemophilia A (37%), followed by all severities of hemophilia A (30%), severe hemophilia B (27%), and all severities of hemophilia B (24%).
“Having 1,125,000 persons with hemophilia worldwide, of whom about 418,000 have severe and mostly undiagnosed disease, constitutes a formidable challenge and burden for researchers and health care systems, especially because only 196,706 patients have been identified and reported globally,” the investigators wrote. “More efficient diagnostic approaches are needed in less wealthy countries to take advantage of current and future treatment modalities, including gene therapy. Increased demand for care should drive new policy planning and spur renewed effort toward the development and manufacture of new drugs.”
The updated prevalence figures will serve as a valuable roadmap for the future, according to J. Michael Soucie, PhD, of the Centers for Disease Control and Prevention, Atlanta.
“Although the magnitude of the global gaps in care for persons with hemophilia is daunting, country specific data generated by application of the prevalence estimates reported by Iorio and colleagues are an important step toward prioritizing efforts to address these gaps,” Dr. Soucie wrote in an accompanying editorial. “Having more accurate prevalence data might also allow identification of ways in which regional efforts to improve care access could generate considerable benefits for patients and cost savings for countries. Armed with these data for action, we can hope to make substantial progress toward the goal of improving the lives of persons with hemophilia wherever they live.”
The study received no financial support. The investigators reported relationships with Pfizer, Roche, Novo Nordisk, and others. Dr. Soucie reported having no conflicts of interest.
SOURCE: Iorio A et al. Ann Intern Med. 2019 Sept 10. doi: 10.7326/M19-1208.