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Heart Health Center

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Take Aspirin at Bedtime to Better Protect Heart?

Small trial found the drug reduced blood clotting more when taken at night than in the morning

WebMD News from HealthDay

By Dennis Thompson

HealthDay Reporter

TUESDAY, Nov. 19, 2013 (HealthDay News) -- A daily dose of aspirin has become a common treatment for people at high risk for heart attacks or strokes, because it thins the blood and prevents clots from forming.

But does it matter when during the day you take the drug?

A new Dutch study suggests that people who take aspirin at bedtime might get more protection against heart attacks or strokes.

The research involved nearly 300 heart attack survivors who were taking aspirin to ward off a second heart attack. During two separate three-month periods, half the patients took 100 milligrams of aspirin after they woke up in the morning while the other half took the same dose at bedtime.

The researchers wanted to see if taking aspirin at night could better thin a person's blood and potentially lower their heart attack risk, said study author Dr. Tobias Bonten, who serves in the department of clinical epidemiology at Leiden University Medical Center in the Netherlands.

"Since the 1980s, it's been known that cardiovascular events happen more often in the morning," Bonten said. Morning hours are a peak period of activity for platelets, blood cells that aid in clotting, he said. Doctors suspect that might have a hand in the increased risk of heart attacks and strokes in the morning.

Aspirin reduces the activity of platelets, and thus reduces the chance that those platelets will clot in the bloodstream and cause a heart attack or stroke, according to the findings. The study is scheduled for presentation Tuesday at the American Heart Association's annual meeting in Dallas.

Research presented at meetings should be viewed as preliminary until published in a peer-reviewed medical journal.

The timing of taking aspirin, however, has not drawn much scholarly attention, said Dr. Gregg Fonarow, a spokesman for the American Heart Association.

"There really have not been studies looking at the timing of aspirin," said Fonarow, a professor of cardiology at the University of California, Los Angeles. "You would imagine that timing of the dose, morning or evening, wouldn't matter very much."

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