Blood Clotting Disorders Research

• Medicine dosing: The Clarification of Optimal Anticoagulation through Genetics (COAG) study was a large-scale clinical study sponsored by the NHLBI that studied participants’ DNA to help determine the proper dose of the blood thinner warfarin for each participant. Results from this study were published in the New England Journal of Medicine. You can also read about common Questions and Answers on NHLBI’s COAG study and how precision medicine may help make warfarin safer.
• Women and blood clots: Women receiving hormone therapy have a higher risk of developing blood clots. The Women’s Health Initiative (WHI) is one of the largest women’s health projects ever launched in the United States, with more than 161,000 participants at 40 clinical centers. The WHI found that the use of estrogen plus progestin hormone therapy after menopause increased the risk of blood clots.
• Causes of disseminated intravascular coagulation (DIC): NHLBI-supported studies laid the groundwork for understanding disseminated intravascular coagulation (DIC), an acquired clotting disorder. These initial studies were critical for later studies on treatments for the condition. For example, studies in the 1980s, such as this one and this one, determined that the clotting factor protein C, which prevents clots, is activated in DIC and plays a major role in controlling the disease. Having low levels of protein C, such as from genetic mutatio mutations , makes people more likely to develop DIC if they have a bacterial infection. Low protein C levels are also linked to blood clots.

Our Division of Blood Diseases and Resources (DBDR) and Division of Lung Diseases (DLD) fund research on blood clots and clotting disorders. DBDR-supported research improves our understanding of normal and abnormal blood, blood clotting, and blood flow. It also supports scientific advances in biomarkers to diagnose blood conditions and in therapeutics to treat them. The DLD funds research on the causes, diagnosis, prevention, and treatment of lung diseases. Its Lung Vascular Biology Program supports research on pulmonary embolism, including understanding how the condition develops.

Current research on acquired clotting disorders

• Sepsis and acquired blood clots: Septic shock can cause blood clots throughout the body that lead to DIC. The risk of death doubles in patients who have sepsis that are diagnosed with DIC. Research funded by the NHLBI seeks to determine the mechanism of the formation of blood clots throughout the body during septic shock. Additional NHLBI-funded studies are examining a new nanoparticle drug that helps prevent blood clots in sepsis.
• Safer treatments for antiphospholipid syndrome (APS): Antiphospholipid syndrome (APS) poses a lifelong risk of blood clots. People with APS typically are prescribed blood thinner medicine that they must take for the rest of their lives to prevent complications of blood clots. Due to the known side effects of blood thinner medicine, NHLBI-funded scientists are actively investigating safer alternative treatment options for people with APS.

Find more NHLBI-funded studies on acquired clotting disorders at NIH RePORTER.

Current research on treatments for clotting disorders

• The role of enzymes: Certain enzymes in the blood, called thiol isomerases, are necessary for blood clot formation. NHLBI-funded researchers are now conducting studies to target these enzymes to stop blood clots from forming in disorders like sepsis, APS, and inherited clotting disorders.
• Warfarin dosage: Many people with clotting disorders and a history of blood clots are prescribed warfarin to prevent more blood clots from forming. NHLBI-funded scientists are researching ways to personalize the dosage based on each patient’s unique genetic and clinical profile.

Find more NHLBI-funded studies on treatment for clotting disorders at NIH RePORTER.

Current research on clotting disorder risk factors

NHLBI-funded researchers are developing tools to help predict who is at greater risk of blood clots with the goal of helping to prevent them.

• Oral contraceptives: People who take oral contraceptives are at an increased risk of developing blood clots. Researchers are conducting studies to examine the effects of oral contraceptive medicine on genetic and nongenetic factors in the blood that form blood clots. Other NHLBI-funded studies are assessing these factors to create a risk-prediction model that could help determine who may be at increased risk of blood clots caused by oral contraceptives.
• Trauma and blood clot risk: Many hospitalized trauma patients develop blood clots. NHLBI-funded researchers are developing a risk tool to accurately predict who is more likely to develop a dangerous blood clot after a traumatic illness or injury.
• Atrial fibrillation and blood clots: Atrial fibrillation is one of the most common types of arrhythmias, or irregular heart rhythms. Sometimes atrial fibrillation goes away on its own, but other times, it can lead to blood clots. NHLBI-funded researchers are developing algorithms to predict the risk of blood clots in people with atrial fibrillation.

Find more NHLBI-funded studies on the risk factors for blood clots at NIH RePORTER.

Our Division of Intramural Research includes some of the investigators at the NHLBI who are actively engaged in the study of blood clots and clotting disorders.

Read more about these projects and ongoing clinical trials.

• In February 2021, the NIH launched the Accelerating COVID-19 Therapeutic Interventions and Vaccines (ACTIV) initiative. As a part of the initiative, researchers funded in part by the NHLBI are exploring the use of a blood thinner to prevent blood clots in patients who have been discharged from the hospital following a diagnosis of moderate-to-severe COVID-19.
• The Vascular Interventions/Innovations and Therapeutic Advances (VITA) Program is a translational program that supports and accelerates early-stage development of promising diagnostics and treatments. The VITA Program seeks to address unmet clinical needs for vascular diseases, including blood clotting disorders, particularly in underserved communities.
• The Trans-Agency Research Consortium for Trauma-Induced Coagulopathy (TACTIC) research program is a partnership between the NHLBI and the Department of Defense to study the disruptions in the normal process of blood clotting that occur in people who experience severe trauma.