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Are you at risk of a blood clot?

Published:Tuesday | March 25, 2014 | 12:00 AM

THE HUMAN body is indeed amazing. The circulation of blood throughout our structure is vital to life, but the blood in our blood vessels must be thin enough to flow freely but at the same time able to clot if the vessels are damaged.

Blood clotting, called coagulation, is then important to prevent excessive bleeding. Specialised blood cells called platelets and certain proteins in the blood called clotting factors work together to stop the bleeding after an injury by forming a clot. Later, after the injury has healed, the body naturally dissolves the blood clot.

Sometimes, however, a dangerous situation develops when without any obvious injury, clots form inside blood vessels and do not dissolve naturally. When a clot forms in a deep vein in the leg or pelvis, this is called a deep vein thrombosis or DVT. With a DVT, you may get a cramping pain, redness, swelling in the leg, or have no symptoms at all.

Sometimes, with a DVT, the clot may dislodge and move to the lungs, creating a life-threatening condition called a pulmonary embolus or PE. It can strike suddenly, causing breathlessness, chest pain, sudden collapse, and even death. Because of this, blood clots must be taken seriously and steps taken to prevent them.

Risk factors for blood clots

Like all disorders, blood clots have a cause, and many lifestyle factors can increase the tendency for unhealthy blood clotting formation.

Inflammation: Whenever inflammation exists in the body, your blood becomes more sticky and clotting is more likely. Infections of any kind, cancer, obesity, diabetes, the metabolic syndrome, liver and kidney disease all increase your risk of clot formation because all are inflammatory disorders.

Homocysteine: This is a toxic amino acid linked to inflammation, and increased blood levels of this substance is a risk factor for blood clots. Your doctor can do a simple blood test to check your homocysteine level.

Not surprisingly, the risk of blood clots is very high in HIV patients, especially if they have other infections.

Inactivity: The more inactive you are, the more sluggish the flow of blood through your body and the more likely it is for clots to form. Prolonged bed rest and immobility are notorious causes of blood clot formation. Sitting with crossed legs for long periods or being confined to a car or aeroplane during a long trip will increase one's risk of clot formation. Interestingly, more blood clots occur in people while in hospital than anywhere else. Their confinement to bed and their underlying medical condition would account for that. Now you have one more reason to keep physically active and remember that deep breathing is a great activity to keep the blood flowing.

Dehydration: This occurs when your body lacks water. This common condition causes your blood vessels to narrow and your blood to thicken, which raises your risk for blood clots. Remember that water accounts for two-thirds of your body and that dehydration is our commonest nutritional deficiency. Especially in hot conditions or in air conditioning, aim to consume half an ounce of water for each pound of your body weight and have lots of water-rich foods like fresh fruit and vegetables.

Medication: Several commonly prescribed medicines elevate your risk of clot formation. Drugs containing the hormone oestrogen like birth control pills and hormone replacement medicines top the list. Research from Europe reveals that popular pain-relieving drugs called NSAIDS (e.g. Voltaren or ibuprofen) greatly increase you risk of clot formation as can several antipsychotic medications (e.g. Risperdal, Seroquel and Zyprexa). Even drugs used to prevent blood clots, like heparin and warfarin, under certain conditions may actually increase the risk.

Lack of vitamin D: Vitamin D obtained from moderate sun exposure has been shown to reduce the risk of deep vein thrombosis. Research from Oregon Health and Science University published in 2006 in the British Journal of Haematology found that high doses of vitamin D were very efficient in decreasing blood clots in patients with prostate cancer - another reason to keep your levels of vitamin D up.

Smoking: This raises the risk of unwanted blood clots in several ways. It increases inflammation, makes the blood platelets more sticky, and also damages the lining of the blood vessels, all of which can cause blood clots to form. Don't smoke!

Stress: It is not well recognised, but stress increases your risk of developing a blood clot. Stress activates what is called the flight or fight reaction in which your body automatically prepares itself to either do battle or escape from a threat, real or imagined. To deal with the possibility of an injury or wound, your blood vessels will constrict and your blood will get thicker and stickier. All this puts your body at higher risk of developing a clot.

So take all the above precautions and avoid blood clots.

You may email Dr Tony Vendryes at or listen to 'An Ounce of Prevention' on POWER 106FM on Fridays at 8 p.m. His new book, 'An Ounce of Prevention, Especially for Women', is available locally and on the Internet.