Blood pressure medications may be more beneficial if taken at night rather than in the morning, according to a study published Tuesday in the European Heart Journal.
A large study of more than 19,000 patients with high blood pressure found that the drug, so that it worked overnight when patients were sleeping, reduced the risk of heart death and disease by almost half.
"The same drug taken at different hours of the day actually has different pharmacological properties, behaving as completely different drugs," says the study's lead author, Ramon Hermida, director of the bioengineering and chronobiology laboratories at Vigo University in Spain
Hermida and his research team randomly selected half of the study participants to take their blood pressure pills in the morning. The other half made the medication part of their sleep.
This team followed the patients for six years, periodically monitoring their blood pressure levels within 48-hour blocks.
The differences in the results were striking: compared to the group that took the pills in the morning, the night clocks were above 40 percent lower risk of experiencing a heart attack, heart failure, stroke, or need for procedures to open obstructed coronary arteries.
Moreover, their risk of dying from heart problems during the study period was reduced by 66 percent.
By taking blood pressure medications at bedtime, you prevent high blood pressure during sleep, which is an important risk factor for cardiovascular disease, Hermida told NBC News.
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Usually a person experiences "night immersion" while sleeping at night: blood pressure "drops" by about 1
But this does not happen in some people and others may even get a rise in blood pressure during sleep, says Dr. Luca Laffin, a preventive cardiologist at the Cleveland Clinic who has not participated in new research.
"It makes sense that if we give blood pressure medications at night, we can catch some of those people who have an undiagnosed pattern or high blood pressure at night," Laffin said, "and protect them from the more cardiovascular diseases. "
Previous research has suggested that better blood pressure control at night can be beneficial."
"That was the missing piece," says Dr. Renato Lopez, a professor of medicine at the University "The Duke School of Medicine.
" For the first time in a very large, randomized flush, this study has really produced impressive results, "said Lopez, who is not involved in the new study.
Although the results are encouraging, researchers say patients with high blood pressure should talk to their doctors before making any changes to their
"It is important to understand that this may not apply to medicines to be taken more than once a day or for blood pressure medications prescribed for other problems such as angina, "Dr. Tim Chico, Professor of Cardiovascular Medicine at the University of Sheffield, United Kingdom, said in a statement.
There are other warnings.
The new study prompted participants to take all their blood pressure medications at one time or night or in the morning, rather some in the morning or some at night. But some cardiologists say many patients may need a more appropriate approach.
"For most people, a combination of several medicines in the morning and several evenings means that you can do better, eliminate side effects and generally have better control of your blood pressure for 24 hours," says Laffin.  Related
And people may not want to take some types of blood pressure medications at night, such as diuretics, because they increase urination.
The study included only white participants, so it's unclear if the obvious benefits would be as much effective for African Americans who have fasting but higher uncontrolled blood pressure and mortality from heart disease.
The results may also not apply to awake people all night, such as shift workers.
In the meantime, just by making sure you are taking medication for blood pressure as a whole, showed a significant reduction in the risk of heart attack and stroke, and anyone measuring more than 130/80 mmHg is considered high in blood, as directed by the American Heart Association and the American College of Cardiology.
The time of day a person measures their blood pressure may also be the key. The readings are usually higher in the morning, so many doctors recommend that those who monitor blood pressure at home take measurements once in the morning and once in the evening.
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