Key Findings: New Study Shows That Regular Treatment for Hemophilia Starting Early in Life Can Prevent Joint Disease

Three young boys standing together

In hemophilia, regular treatment to prevent bleeding (prophylaxis) can prevent joint disease when started early in life.

Therapies and healthcare delivery for men and boys with hemophilia have improved over the last five decades. Yet people affected by hemophilia still experience significant health challenges.

In order to better address these challenges, it will be important to monitor and learn more about the health of people with hemophilia. This knowledge can be used to develop programs to help decrease illness and death from this disorder.

About the Study

Researchers from the Centers for Disease Control and Prevention (CDC) and the U.S. Hemophilia Treatment Center Network analyzed data from a health monitoring system that tracked care and health outcomes of boys and men with hemophilia in the United States. The study aimed to examine

  • Trends over time in the use of regular treatment to prevent bleeding episodes, called prophylaxis;
  • Changes over the same period in the health of each person’s joints (such as the average number of bleeding episodes into a person’s joints and the ability of the joints to move properly); and
  • The effect of beginning prophylaxis at various ages on the health of a person’s joints over time for those between 2 and 19 years of age.

Researchers studied information collected from 6,196 males between 2 and 69 years of age with severe hemophilia A. These males received care at U.S. hemophilia treatment centers from 1999-2010. The data collected from all of their clinic visits were used to examine trends in prophylaxis use and changes in their health over the study period. In a separate study, data collected during the same period from 2,908 boys and young men were used to determine the age at which beginning prophylaxis worked best to preserve the ability of their joints to move properly.

We invite you to read the scientific summary of the study.

What is Hemophilia

Hemophilia is an inherited bleeding disorder in which the blood does not clot properly. This can lead to spontaneous bleeding as well as prolonged bleeding following injuries or surgery.

Blood contains many proteins called clotting factors that can help to stop bleeding. People with hemophilia have low levels of either factor VIII (“factor eight”) or factor IX (“factor nine”). Because of the way hemophilia is inherited, the condition predominantly affects males, while females with the genetic change in the clotting factor are typically referred to as carriers. Hemophilia carriers can have an increased bleeding tendency, such as heavy menstrual bleeding.

Main Findings from the Study

  • The use of prophylaxis by hemophilia patients to prevent bleeding increased from about one-third of patients in 1999 to half of all patients by the end of the study period.
  • Prophylaxis use was greater among patients younger than 20 years old with 3 in every 4 of these patients using this treatment to prevent bleeding by 2010.
  • Bleeding episodes in joints as well as in other places in the body decreased during 1999-2010, and in most cases the decrease was greater for those patients using prophylaxis.
  • Among patients under age 20, prophylaxis resulted in less bleeding at any age. However, only those who started prophylaxis before age 4 or those who were not obese, meaning they did not have excess body fat, retained the ability to move their joints normally.

Public Health Message

Starting young children with severe hemophilia on prophylaxis before age 4 years is the most effective way to preserve healthy joint function over the lifespan.

Critical Gaps in Information & Future Work

Gaps in Information

A number of observations from this study need further investigation to determine why they occur:

  • Prophylaxis through the regular infusion or injection of clotting factor concentrates into a vein to prevent bleeding was shown to result in better joint health. However, this study found that not everyone with hemophilia used prophylaxis.
  • It is not known why prophylaxis is best able to protect the ability of joints to move properly only when treatment is started at a very young age.
  • It is not known why all people with hemophilia don’t use prophylaxis, and what might be the barriers that keep them from using this treatment.

Future Work

Studies are needed to understand why some boys and men with hemophilia do not use prophylaxis and to develop strategies that are successful in changing this behavior. More work is needed to understand the factors that may lead to joint bleeds and develop treatment strategies for men with hemophilia who have a higher risk for joint disease.

More Information

Please visit the following links for more information:



Public health monitoring programs for hemophilia and other bleeding disorders

Key Findings Reference

Manco-Johnson MJ, Soucie JM, Gill JC. Prophylaxis usage, bleeding rate and joint outcomes of hemophilia 1999 – 2010: a surveillance project. Blood. 2017 Feb 9. pii: blood-2016-02-683169. doi: 10.1182/blood-2016-02-683169. [Epub ahead of print]