Hemophilia 3 times as prevalent in men than originally thought: study

A well-known genetic disorder that prevents blood from clotting is more prevalent in men than originally thought, according to a recent study published in the Annals Of Internal Medicine.

Researchers at McMaster University in Hamilton say the study has shown that close to 1,125,000 men around the world have hemophilia — three times more than the previous estimate of 400,000.

The probe also showed that close to 418,000 of those men had a severe version of the disease.

Hemophilia is a defect that comes in two types: hemophilia A has a factor 8 (F8) gene defect, and hemophilia B has a factor 9 (F9) gene defect. Both are genes that encode instructions for making proteins that help clot blood.

Lack of treatment for the disorder can lead to chronic and debilitating joint disease, while bleeding into organs and brain hemorrhages can lead to disability and death.

Researchers say that for every 100,000 men, 21 will have hemophilia A or B, with seven having the severe version. Meanwhile, for every 100,000 newborn boys, 29 will have hemophilia A or B, with 12 having the severe form of the disease.

Dr. Alfonso Iorio, lead author of the paper and health sciences professor at McMaster, says the “life expectancy disadvantage” associated with hemophilia varies depending on the availability of care.

According to the study, those born with hemophilia will likely see a 64 per cent reduction in the quality and duration of life if they live in an upper-middle-income country. Those who live in countries considered largely middle income will see a 77 per cent drop in their quality of life, while the number is 93 per cent for those residing in low-income countries.

“Knowing how many patients are expected in each country, given its population, is an important measure of the efficiency of the health-care system,” said Iorio.

“Knowing how many patients are out there will enable health-care systems to estimate the resources needed to treat the disease and enable drug manufacturers to increase the investment in research to match the demand of a patient population three times larger than we previously thought.”

The study was completed by an international team of researchers from France, the U.S. and the U.K. which used data from countries with the most comprehensive registries of hemophilia, including Australia, Canada, France, Italy, New Zealand and the U.K.