Having an irregular heartbeat
Unfortunately, in many cases, there are no symptoms of an irregular heartbeat, but it does increase your risk for blood clots. “Atrial fibrillation is a kind of irregular heart rhythm that can put you at increased risk of blood clot formation in the upper chambers of the heart,” says Okeke-Igbokwe.
Cancer
“Some forms of cancer increase the amount of substances in your blood that cause clotting,” says Harnett. People with cancers of the brain, ovary, pancreas, colon, stomach, lung, and kidney have the highest risk of DVT.
Your age
DVT can occur at any age, but the older you are, the higher your risk is. “Being over 60 can up your chances of a clot,” says Harnett. “Approximately 1 in every 1,000 people will develop a DVT or PE each year, and this increases from about 1 in 10,000 for those in their 20s to about 5 in 1,000 for those in their 70s.”