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Your FAQs Around Hemophilia A

Many people with hemophilia A can lead ordinary, active lives. Learning more about this genetic condition can support effective long-term management strategies.

Hemophilia A is a genetic condition that is present from birth. It can be inherited or de novo (caused by a genetic change that occurs during embryonic development). Like other types of hemophilia, hemophilia A prevents proper blood clotting.

This article explores the frequently asked questions about hemophilia A, including its causes, severity, and impact on quality of life.

Hemophilia A is one of two primary types of hemophilia — the other is hemophilia B. Hemophilia A is a genetic condition that prevents the body from making enough of clotting factor VIII (factor 8). Clotting factors are proteins in the blood that are involved in coagulation (clot formation).

Clots are part of the body's healing process. They control blood loss and create a matrix that supports tissue repair.

People with hemophilia A have a genetic change on the F8 gene of their X chromosome that affects the production of clotting factor VIII. Without enough clotting factor VIII, coagulation is interrupted. As a result, clots may not form, may form slowly, or may not be stable if they do form.

Hemophilia A varies in severity, depending on how the F8 gene is altered. Genetic changes can result in a mild, moderate, or severe deficiency of clotting factor VIII. The lower the level of clotting factor VIII, the more serious the bleeding can be.

Mild hemophilia A, which involves clotting factor VIII levels of 6% to 40%, rarely causes spontaneous bleeding (episodes of internal hemorrhaging that result from an unknown cause or from everyday activities). Though it is considered mild, this type of hemophilia A will still result in prolonged or excessive bleeding as a result of minor tissue trauma.

Bleeding episodes are more common in severe hemophilia A. With clotting factor VIII levels of less than 1%, severe hemophilia A may periodically cause spontaneous bleeding.

The life span for someone with hemophilia A varies depending on the severity of the condition and on individual factors such as age, co-occurring conditions, and medical management.

Research suggests that hemophilia has an association with a lower life expectancy overall. In a 2020 study involving more than 1,000 men in the Netherlands, researchers found that the median life expectancy for those with hemophilia was 77 years — 6 years lower than the median for the larger population of men.

In a 2023 study in the United States, researchers found that between 1999 and 2020, the median life expectancy for males with hemophilia increased from 54.5 to 65.5 years. However, racial disparities were significant, with a 12-year difference in the median age at end of life between non-Hispanic Black males (56 years) and non-Hispanic white males (68 years).

Quality of life (QoL) is a measurement of how well a person feels. In hemophilia A, QoL varies depending on the severity of the condition and individual variables such as overall health, lifestyle habits, and treatment adherence.

A 2019 survey found that health-related QoL among people with severe hemophilia A was low. The most common challenges that survey participants cited were pain, anxiety, depression, and physical limitations due to joint pain.

QoL in milder forms of hemophilia A may be higher. With treatment and safety measures, many people can maintain ordinary levels of activity and function.

Hemophilia A primarily affects males due to inheritance patterns. The condition appears on the X chromosome.

In females, two X chromosomes are present (XX), one from the father and one from the mother. Males have one X chromosome from their mother and a Y chromosome from their father (XY).

In females, an unaffected X chromosome can compensate for the F8 genetic change on the other X chromosome. However, because males have only one X chromosome, the altered F8 gene will affect the production of clotting factor VIII.

Females can still have factor VIII deficiency if the second X chromosome is not working or if both X chromosomes have the genetic change, but males are more likely to experience severe bleeding.

This means females with an F8 genetic change are less likely to have significant symptoms, while all males with an F8 change for hemophilia A will have clotting factor VIII deficiency.

Clotting factor VIII deficiency in hemophilia A does not worsen with age. If a person does not receive treatment for the condition, the severity that is present at birth will remain consistent throughout the person's life.

However, hemophilia A symptoms may become more noticeable as a result of natural age-related changes in the body, illness, chronic injury, or co-occurring medical conditions. Over time, spontaneous bleeds can cause long-term damage to some areas of the body, such as the joints.

Hemophilia A affects the body's ability to form blood clots. It is a genetic condition caused by a change in the F8 gene on the X chromosome.

With treatment and everyday safety precautions, many people with hemophilia A can lead active, ordinary lives. Quality of life and life expectancy can vary depending on factors such as the condition's severity and a person's age, lifestyle, and co-occurring medical conditions.

Saliva Activates Coagulation In Persons With Hemophilia A

A recent study led by MedUni Vienna provides new insights into the mechanisms of coagulation in persons with haemophilia A, the most common form of haemophilia. The research team was able to show that saliva contains special vesicles that trigger rapid coagulation of the blood of haemophilic patients. The results, which were recently published in the scientific journal Blood, contribute significantly to a better understanding of the disease.

Haemophilia is a hereditary blood disorder characterised by a deficiency of certain coagulation factors, which can lead to life-threatening bleeding if left untreated. Why haemophilia A (with factor VIII deficiency) often leads to joint bleeding, but rarely to mucosal bleeding, was previously unclear. In search of an explanation, the scientific team led by Johannes Thaler and Cihan Ay (Clinical Division of Hematology and Hemostaseology, Department of Medicine I, MedUni Vienna) and Rienk Nieuwland (Amsterdam University Medical Centers) studied research into the importance of the body's own fluids for blood coagulation, which had been forgotten for decades.

The researchers discovered that the saliva of haemophilia A patients contains extrinsic tenase complexes, which are located on vesicles. Extrinsic tenase complexes are protein complexes that consist of two coagulation factors (tissue factor TF and factor VIIa) and initiate the activation of the coagulation cascade when they come into contact with blood. Analyses by the study authors confirm that mucosal bleeding in the mouth of these patients is indeed rare and stops quickly. Patients without this protein complex in their saliva lack this protective mechanism. "They therefore often suffer from oral mucosal bleeding," reports Johannes Thaler.

Body fluids as activators of blood coagulation

The importance of body fluids for coagulation was first described in the 1930s. At that time, the average life expectancy of haemophilia patients was just eight years. The Viennese paediatrician Alphons Solé discovered that maternal milk is a strong activator of coagulation. In a clinical study, he showed that tamponades soaked in maternal milk quickly brought acute, previously unstoppable bleeding to a halt in haemophilia patients. However, Solé's findings, which were confirmed by independent researchers, were forgotten. It was only a few years ago that the team led by Johannes Thaler, Cihan Ay and Rienk Nieuwland revived this historical research. The scientists were able to prove that the coagulation-promoting properties of maternal milk, amniotic fluid, urine -- and now also saliva -- are due to the presence of extracellular vesicles with extrinsic tenase complexes.

The results provide important insights into the mechanisms of coagulation and contribute to a better understanding of haemophilia A. "At the same time, they show that it can be very rewarding to re-evaluate historical scientific work in order to develop innovative approaches for research and potentially also for the targeted treatment of patients," says Johannes Thaler about the significance of the findings.

Moving For A Job Isn't As Frightening As It Used To Be

I'm a pastor in the United Methodist Church, where the one constant we share is change. In our denomination, pastors serve on an itinerant system, which means that the cabinet (the bishop plus the district superintendents) chooses which pastors will serve in different locations. As a result, I'll move from Belen, New Mexico, to Las Cruces, farther south in the state, at the end of June. My new church will be St. Paul's United Methodist Church.

When the cabinet asked us to move in the past, our first concern was the new congregation's proximity to a hemophilia treatment center (HTC). Because Caeleb, my youngest son, had already experienced complications of hemophilia, we needed to be close to the University of New Mexico Hospital in downtown Albuquerque. We depended on our experienced medical team when making decisions regarding my son's healthcare.

No other medical facility in the state has a treatment center focused solely on meeting the needs of those living with bleeding disorders. Hemophilia A — the condition that both of my sons live with — is rare, affecting approximately 1 in 5,000 live male births. As a result, many medical professionals know little, if anything, about treatment.

This lack of knowledge outside of HTCs is why, when asked to move to a new church before, I couldn't take some assignments. The risk of complications for both Caeleb and his older brother, Julian, proved too great to accept a change.

Years ago, when preparing for my ordination service, Caeleb started having a bleed in his right ankle. We were in a small, rural city and knew he needed to see a doctor. My wife, Cazandra, took Caeleb to a nearby emergency room (ER), where she told the attending medical team precisely what she'd seen and suggested that our son needed a factor VIII infusion.

Luckily, my fast-thinking wife called the HTC in Albuquerque and asked if someone could speak to the doctor on call regarding my son's condition. The ER physician agreed to talk to our hematologist, and together, they stopped the internal bleeding in my boy's right ankle. We breathed a sigh of relief as Caeleb's pain decreased significantly. I arrived in time to see my boy preparing for discharge from the small hospital.

Cazandra and I discussed the situation in the car and agreed that the visit reminded us of the importance of access to our HTC in Albuquerque. We thanked God that the ER doctor didn't mind receiving instructions from our hematologist. But we also knew we couldn't be sure that all doctors would follow the same protocol. The ER physician could've refused to talk with our medical team and instead administered treatment that might've proven detrimental to our son's psychosocial development.

We've come a long way

Now, our situation is different. In the fall, Caeleb will move into a dormitory at the University of New Mexico, right across the street from the hospital. We don't need to worry about his care. He will soon be 19 years old, and our new location — about 200 miles south of where we live now — will allow him to take charge of his medical needs. We can offer him support from a distance.

Cazandra and I are excited about our next chapter. While we prepare for our move, we feel confident that Caeleb has the tools he needs to handle his bleeding disorder. He has the doctor's and pharmacist's telephone numbers on his cellphone. I smile and say, "Thank you, dear God." We feel all will be well, but we can return to Albuquerque in less than three and a half hours if something goes awry.

When Cazandra and I initially talked about the move to Las Cruces, it felt like something was missing. We met with key leaders at the new church and set a moving date, but something still didn't feel right. Finally, we realized that, in all our planning, we hadn't considered a bleeding disorder. We looked at each other, smiled, and I told her in my best Elvis impersonation, "We've come a long way, baby. Thank you. Thank you very much."

Note: Hemophilia News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or another qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website. The opinions expressed in this column are not those of Hemophilia News Today or its parent company, Bionews, and are intended to spark discussion about issues pertaining to hemophilia.

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