A blood clot in a deep vein, usually in a leg, is called a deep vein thrombosis, or DVT. It is dangerous because a piece of it can break off, travel to the lungs, and block blood flow there. That is a pulmonary embolism, or PE, and it can kill within minutes. Together the two conditions are called venous thromboembolism (VTE). Up to 900,000 Americans are affected each year, and 60,000 to 100,000 die. Black Americans carry more of that burden than any other group.
Why this hits Black adults harder
The gap is real and it is measured. In the Atherosclerosis Risk in Communities study, the lifetime risk of a first blood clot between ages 45 and 85 was 11.5% in Black participants compared with 6.9% in white participants, and the incidence rate ran about 65% higher in Black adults over the full follow-up (Folsom and colleagues, American Journal of Medicine, 2019). The outcomes gap is wider than the incidence gap. A national analysis of 109,992 pulmonary embolism deaths found Black Americans died at an age-adjusted rate of 5.26 per 100,000 versus 2.91 for white Americans, more than double (Zghouzi and colleagues, Annals of the American Thoracic Society, 2023).
Several things drive the disparity. A 2025 American Heart Association scientific statement reports Black patients are about 1.9 times more likely than white patients to be hospitalized for PE and carry a nearly 50% higher rate of all-cause death after one (15.0% versus 10.7%). The same statement found Black patients are less likely to receive clot-busting interventional treatments such as catheter-directed therapy and surgical clot removal (Circulation, 2025). One inherited factor matters here: sickle cell trait, carried by roughly 1 in 13 Black Americans, roughly doubles the risk of pulmonary embolism. In a prospective study it accounted for about 7% of blood clots among Black participants (Folsom and colleagues, American Journal of Hematology, 2015). Higher rates of obesity, clotting-protein levels, and gaps in timely care fill in much of the rest.
Leg DVT warning signs, and the dark-skin trap
A leg clot usually announces itself in one leg, not both. The CDC lists four signs: swelling, pain or tenderness (often a cramp or ache in the calf), warmth in the area, and redness or discoloration of the skin (CDC). The catch for Black readers is the fourth one. On brown and dark skin a clot does not usually turn bright red. It can read as a dusky, bruise-like, or simply off color that blends in and is easy to miss, the same blind spot that delays diagnosis of skin and circulation problems across darker skin tones. So do not wait for redness. If one leg is swollen, painful, and warm, treat that as the signal even if the color looks normal to you.
Roughly half of people with a DVT have no symptoms at all, which is part of why the lungs are sometimes the first place anyone notices a problem. If you have already lived with leg-circulation issues, the overlap matters: read our explainer on peripheral artery disease in Black adults so you can tell the two apart and flag either one to a clinician.
The lung clot signs that mean call 911
A pulmonary embolism is the emergency. The CDC lists these warning signs: difficulty breathing that comes on suddenly; chest pain or discomfort that usually worsens with a deep breath or a cough; a faster than normal or irregular heartbeat; coughing, sometimes coughing up blood; and very low blood pressure, lightheadedness, or fainting (CDC). Sudden death is the first sign in about one in four people who have a PE. You do not have time to schedule an appointment or wait it out. If you or someone near you has sudden breathlessness, chest pain with breathing, or faints, call 911.
When your risk spikes
Clots form when blood sits still, when a vein is injured, or when the blood is primed to clot. The CDC names the common triggers: long stretches without moving, including bed rest and long flights or drives; surgery and hospital stays (about half of all clots start during or soon after one); pregnancy and the first three months after delivery; extra estrogen from birth control pills or hormone therapy; cancer and its treatment; chronic heart, lung, or inflammatory disease; obesity; a central IV line; older age; and inherited clotting disorders or a family or personal history of clots (CDC). Smoking adds to the load. Pregnancy is a sharp one for Black women, whose maternal risks are already elevated. If you are pregnant or recently delivered, our guide to postpartum warning signs for Black mothers covers the leg and breathing symptoms that warrant a same-day call.
Preventing a clot you can see coming
As many as 70% of healthcare-associated clots are preventable (CDC). On a flight or drive over four hours, stand, walk, or flex your calves every hour or two and stay hydrated. Around any surgery or hospital stay, ask what the clot-prevention plan is: blood thinners, compression devices, or compression stockings are standard, and you can confirm you are getting them. If clots run in your family or you carry sickle cell trait, say so before any surgery or long hospitalization so the team can plan around it.
Treatment works when you move fast
The core treatment for a DVT or a PE is an anticoagulant, a blood thinner that stops the clot from growing and lets the body break it down while preventing new ones. Most people take a direct oral blood thinner for at least three months, sometimes longer depending on what caused the clot. A large or unstable PE may need clot-busting drugs or a catheter procedure in the hospital. A blood clot caught early is very treatable. The danger is delay, and delay is exactly where the racial gap shows up. Speaking up about your symptoms is part of the treatment.
How to get care
For an emergency, the ER is the right door. For everything short of that, build a relationship before you need it. A primary care clinician can assess your risk, order leg ultrasound or imaging when symptoms appear, and refer you to a hematologist if you have a clotting disorder or a clot that keeps coming back. You can find a Black primary care clinician or hematologist in our directory and start with someone who will take a swollen leg or a family history of clots seriously the first time you raise it.
Frequently asked questions
What does a blood clot in the leg feel like? ▼
Usually swelling in one leg, with pain or a cramp or tenderness that is often in the calf, plus warmth in the area. The skin may look reddish, darker, or discolored, but on brown and dark skin that color change is subtle and easy to miss. Trust the swelling, pain, and warmth even if the color looks normal.
How do I know if a clot has reached my lungs? ▼
A pulmonary embolism causes sudden shortness of breath, chest pain that gets worse when you breathe in or cough, a fast or irregular heartbeat, coughing that may bring up blood, and lightheadedness or fainting. These are 911 symptoms. Sudden death is the first sign in about one in four people who have a PE.
Why are Black Americans at higher risk for blood clots? ▼
The lifetime risk of a clot is 11.5% for Black Americans versus 6.9% for white Americans, and the death rate from pulmonary embolism is more than double. The drivers include higher rates of obesity and certain clotting-protein levels, sickle cell trait (which roughly doubles PE risk), and gaps in timely diagnosis and access to advanced clot treatments.
Are blood clots treatable? ▼
Yes. The main treatment is an anticoagulant, a blood thinner that stops the clot from growing and prevents new ones, usually for at least three months. A large or unstable lung clot may need clot-busting drugs or a catheter procedure. Caught early, a blood clot is very treatable. The danger is waiting too long to get checked.
Can I prevent a blood clot on a long flight or after surgery? ▼
Often, yes. On long flights or drives, get up and move or flex your calves every hour or two and stay hydrated. Around surgery or a hospital stay, ask what the clot-prevention plan is; blood thinners and compression devices are standard, and as many as 70% of healthcare-associated clots are preventable.
