Taking blood pressure pills at bedtime rather than in the morning could cut the risk of heart attacks, heart disease and strokes, according to a new study.

The research, published in the European Heart Journal, is the biggest study of its kind to investigate whether the timing of taking drugs affects health outcomes.

Almost 20,000 people with high blood pressure were split into two groups for a clinical trial, with the first taking their entire dose of pills at night and the rest when they woke up.

Image: Almost 20,000 people with high blood pressure were involved in the study

The groups then had their blood pressure monitored over a period of 48 hours at least once a year.

Over a follow-up period of six years, 1,752 patients on the trial died from cardiovascular disease, had a heart attack, suffered heart failure or stroke, or had a coronary revascularisation procedure to unblock narrowed arteries.


Compared to those who took their pills in the morning, people who took them in the evening had a 66% lower risk of death from heart disease; a 44% reduced chance of a heart attack; and a 40% lower risk of coronary revascularisation.

They were also 42% less likely to have heart failure and almost half had a lower risk of stroke - even when factors likely to influence the results were taken into account, such as cholesterol levels and gender, and whether people smoked or had Type 2 diabetes.

The research was led by a team from the University of Vigo in Spain.

Author Professor Ramon Hermida said: "Current guidelines on the treatment of hypertension do not mention or recommend any preferred treatment time.

"Morning ingestion has been the most common recommendation by physicians based on the misleading goal of reducing morning blood pressure levels."

He added that blood pressure levels when a person is asleep are a significant indicator of cardiovascular disease risk - and that taking pills at night helps to lower blood pressure at this time.

The findings have been described as "impressive" - by Tim Chico, professor of cardiovascular medicine at the University of Sheffield.

He said that given there was little risk in taking medication before bedtime, there was "enough evidence" to recommend they do just that, but he said patients should speak to their doctor first.

Another expert said the study has "the potential to transform how we prescribe blood pressure medication".

Paul Leeson, professor of cardiovascular medicine at the University of Oxford, said: "The scale of the project, length of follow-up and size of effect are impressive.

"Importantly, this is a 'real world' study where doctors were allowed to prescribe whatever they wanted and just change medication timing.

"This means the findings are likely to be relevant to most people who take tablets for high blood pressure."

The British Heart Foundation said that, while the study supported previous evidence, further research was needed.

Image: The British Heart Foundation said further research was needed

Vanessa Smith, senior cardiac nurse at the charity, also had a warning for patients: "If you're currently taking blood pressure medication, it's important to check with your GP or pharmacist before changing the time you take it.

"There may be specific reasons why your doctor has prescribed medication in the morning or night."