You might want to change the time of day you take your blood pressure medicine

You may want to take your blood pressure medicine at bedtime rather than when you get up in the morning, according to a study published Tuesday in the European Heart Journal.

The research found that people who take their anti-hypertensive medicine before bed had better-controlled blood pressure and consequently had a much lower risk of death or illness from heart problems when compared to people who took their medication in the morning.

Compared to those who took their medicine in the morning, the people who took their medicine at night had nearly half the risk of dying from heart problems and nearly half the risk of having heart attack, stroke, heart failure, myocardial infarction or of needing a procedure to unblock their arteries.

When researchers looked at individual heart problems, those who took their pills at night saw their risk of death from heart or blood vessel problems reduced by 66%. The risk of stroke went down by 49%. The risk of myocardial infarction went down by 44%. Heart failure risk went down 42% and coronary revascularisation by 40%.

Researchers figured this out looking at data from 19,084 patients enrolled in the Hygia Project, a network of care centers in Spain. Scientists compared the results for people who took their pills at night versus those who took them when they got up in the morning. They followed these patients for more than six years. The patients’ blood pressure was checked over 48 hours at least once a year.

The authors argue that there is no significant study that shows that taking blood pressure medicine works best in the morning, although it is common practice for doctors to recommend taking it when you wake up.

“Morning ingestion has been the most common recommendation by physicians based on the misleading goal of reducing morning blood pressure levels. However, the Hygia Project has reported previously that average systolic blood pressure when a person is asleep is the most significant and independent indication of cardiovascular disease risk, regardless of blood pressure measurements taken while awake or when visiting a doctor,” author Dr. Ramon Hermida said in a statement. Hermida works with the Bioengineering and Chronobiology Laboratories at the University of Vigo, Spain.

More research will need to be done to see if the results can be replicated in other ethnic groups.

“We have been waiting for this, this is a practice changing study,” said Dr. John A. Osborne, who was not involved with the study, but is the director of cardiology at State of the Heart Cardiology in Southlake, Texas and serves as a volunteer with the American Heart Association.

Osborne said that he had noticed the smaller trial done by this group that showed similar results and had been watching for the outcome of this larger study. To see these “astounding” results in a much bigger group of people in a real world setting, “it is practice changing data.”

When asked why doctors may have told their patients to take their medicine in the morning, Osborne said it may have been that doctors thought it would be easier for people to remember to take their pills in the morning or it may have been because some high blood pressure medicines are diuretics.

“You probably don’t want to take a pill at night that will make you get up and pee, but after a few weeks, this progressively becomes less of a problem, so that shouldn’t be an issue,” Osborne said. “Especially when you see there is such a benefit to this.”

Dr. Barbara Roberts, a cardiologist and associate clinical professor of medicine at Brown, said she applauds the scientists who did this work. “I believe you will see doctors come around to this quickly,” Roberts said. “Hypertension is such a strong risk factor for cardiovascular disease, far greater than cholesterol and everything that will allow us to treat this more effectively is important.”

Dr. Tim Chico, who was not involved with the study, but is a professor of cardiovascular medicine and honorary consultant cardiologist at the University of Sheffield, told Science Media Centre in the UK that the results were “impressive.” He said you should talk to your doctor, as with any change in your routine, and he said there will need to be further studies to confirm these results.

“However, as taking medications at bedtime poses little risk,” Chico said, “there is enough evidence from this study to recommend that patients consider taking their medication at bedtime.”