Blood Clot Drug Warfarin Linked with Heart Attack Risk

Warfarin - a drug used to treat blood-clots can raise the risk of heart attacks, a new study reported.

The drug is already known to cause severe health complications in some people. Now, researchers at Monash University and their colleagues have found that the drug lowers vitamin K, which increases calcification of organs and can lead to heart-attack risk.

Warfarin belongs to a group of drugs called anticoagulants or "blood thinners".  The drug decreases blood's ability to clot. The drug is also given to patients with certain kind of irregular heartbeat, people with prosthetic heart valves and even those who have suffered a heart attack.

Vitamin K is a fat-soluble vitamin and is known to help in clotting blood. Foods such as fish, liver, meat, spinach, turnip greens and collard are good sources of vitamin K. People on anticoagulants are advised to limit intake of foods that have high levels of vitamin K. Apart from clotting, the vitamin is also associated with maintaining bone-density in older people.

In the study, researchers looked at a case of calcification in a patient who was on warfarin for ten years.

"It's commonly believed that the only effect of vitamin K deficiency is blood clotting, but it's becoming increasing clear that vitamin K has many important functions in the body in the bones, the brain, arteries and other tissues and systems," said Professor Wahlqvist, former head of medicine at the Monash Medical Centre "In the case of vascular (blood vessel) walls, vitamin K-dependent proteins (VKDPs) help prevent calcification and hardening of the coronary and other arteries.

The patient, researchers said, had no known risk factors for heart disease, but had increased rate of calcification after taking the drug. According to researchers, doctors prescribing the drugs must know that vitamin K doesn't just affect clotting, but is also important for many other functions.

"When an individual has a Vitamin K deficiency, the body does not mineralise bones properly, resulting in weak bones and osteoporosis. Along with this, calcium is deposited around organs like the heart and kidney. This calcification of organs can lead to organ failure and life-threatening problems," Wahlqvist said in a news release.

Note- People shouldn't discontinue or change the dose of any prescribed drug without consulting a physician.