New U.S. Study Provides a Bigger Picture of Glanzmann Thrombasthenia

A large U.S. study is providing new insight into how common Glanzmann Thrombasthenia (GT) may be and how the condition affects people in everyday life.

Researchers analyzed health records from 1,059 people with Glanzmann Thrombasthenia using a large healthcare database containing records from hospitals and clinics across the United States.

The study examined GT prevalence, bleeding, anemia, transfusions, medications, and mortality between 2013 and 2024.

What Did the Glanzmann Thrombasthenia Study Find?

One of the biggest findings was that Glanzmann Thrombasthenia may be more common in the United States than previously thought.

GT has historically been estimated to affect approximately 1 in 1 million people. This study identified 1,059 people with GT suggesting that previous estimates may not capture everyone living with the disorder.

Researchers also found a significant burden from GT bleeding symptoms:

• 51.9% had at least one documented bleeding event
• 22.6% experienced nosebleeds
• 16.1% had blood in the urine
• 13% had melena, which can be a sign of gastrointestinal bleeding
• 29.7% of females ages 11–45 had abnormal uterine bleeding
• 2.3% had a documented intracranial hemorrhage

These numbers reflect only bleeding documented in medical records, so they may not include every bleeding episode patients experience.

Anemia Was Common in People With GT

Anemia was another major finding.

About 31% of people with GT had iron-deficiency anemia, compared with just 3.3% of the general population included in the study.

Repeated blood loss from nosebleeds, menstrual bleeding, gastrointestinal bleeding, and other bleeding episodes can contribute to iron deficiency over time.

The results highlight why monitoring iron levels and anemia can be an important part of caring for someone with Glanzmann Thrombasthenia.

Many GT Patients Required Transfusions

The researchers also found significant use of blood and platelet transfusions.

About 12.7% received red blood cell transfusions, while 11.3% received platelet transfusions. Overall, 16.4% received at least one blood or blood-component transfusion.

The study also documented the use of several medications and approaches commonly used to help manage bleeding and anemia in people with GT.

You can learn more about Glanzmann Thrombasthenia treatment and bleeding management.

Is Glanzmann Thrombasthenia More Common Than We Thought?

This study suggests that it could be.

Previous estimates have often relied on patients treated through specialized bleeding disorder centers. A large electronic health record database may identify additional people receiving care outside those centers.

However, the researchers also noted important limitations. Not every healthcare system uses Epic, medical records can be incomplete, and identifying patients through diagnostic codes can occasionally result in incorrect classifications.

The study therefore does not tell us exactly how many people in the United States have GT, but it provides evidence that the population could be larger than previously recognized.

Why Is This GT Research Important?

With more than 1,000 patients included, this is one of the largest real-world studies of Glanzmann Thrombasthenia in the United States.

The findings show that GT is about more than individual bleeding episodes. Repeated bleeding can contribute to anemia, transfusions, and other health complications over a lifetime.

Better identification of people with GT may also help researchers understand the condition, improve care, and support future Glanzmann Thrombasthenia research.

The Glanzmann’s Research Foundation continues to follow and share new research to help make complex scientific findings easier for patients, families and caregivers to understand.

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