A daily dose of aspirin at night can help avoid many deadly heart attacks that usually occur in the early morning, researchers reveal.looseid/Flickr

A daily dose of aspirin at night can help avoid many deadly heart attacks which usually occur early morning, researchers reveal.

Aspirin has long been known to help prevent heart attack. In most cases, heart attack occurs either in the early morning or during the last stages of sleep. According to experts, the risk of developing heart attack or other cardiovascular complications at 6 am is 40 percent higher than the noon. However, there hardly exists any solid evidence about the right time that gives the maximum effect of the drug.

For the study, Dr Tobias Bonten from the Leiden University Medical Center in the Netherlands and colleagues looked at 290 people suffering from various types of cardiovascular diseases. The participants took a daily dose of 100mg aspirin at night for the first three months and in the morning for another three months. During each session, blood pressure and platelet activity of the participants were measured and recorded. Platelet is one of the important components of the blood. Changes in the platelet activation have known to play a major role in cardiovascular disorders.

Results showed that bedtime aspirin thinned blood and helped reduce platelet activity by 22 units.

"Because higher platelet activity contributes to a higher risk of acute heart events , this simple intervention - switching aspirin intake from morning to bedtime - could be beneficial for the millions of patients with heart disease who take aspirin on a daily basis," Dr Bonten, said in a statement.

The study has been presented at the American Heart Association's Scientific Sessions 2013, recently.

During an interview with TIME, Roberto Manfredini, professor of internal medicine at the University of Ferrara in Italy, explained the factors that increase the risk of heart attack in the morning. According to him, heart attacks occur when the body fails to meet the increased myocardial oxygen demand needed to start off the physical activities in the morning. Apart from that, levels of the hormone called cortisol goes up after waking up in the morning, further leading to a dramatic increase in blood sugar, blood pressure and heart rate. All these processes consume majority of the oxygen levels in the body, at the same time reduce vessel size, restricting the flow of blood to the coronary vessels.

Another factor that contributes to heart attack is the reduced activity of fibrinolytic system in the morning. The system helps dissolve blood clots and the reduced activity affects the blood flow. A healthy person can always withstand these changes but for a person with heart problems, mainly diagnosed with atherosclerosis (accumulation of plaque on the artery walls and narrowing and hardening of arteries), these changes can often prove to be deadly.

Manfredini also added that the last stage of sleep, which involves rapid eye movement (REM) and dreaming, poses serious risk to the heart. Dreaming leads to a sudden increase in the activity of the autonomic nervous system and needs lots of oxygen, making it hard to many heart patients to survive the situation.