Heart attacks are more likely to happen in the morning.

Heart attacks that occur in the morning are far more dangerous than at any other time of the day, research shows.


Patients struck down between 6am and midday suffer a fifth more damage to their heart muscle compared with those who have an attack later on.

Scientists believe the phenomenon may be due to the changes in the body’s blood pressure, hormone levels and metabolism rates that naturally occur when a person wakes up.

It is already well established that heart attacks are more likely to happen in the morning than other times of the day, but the latest study is the first to show that they are also more severe at this time of day.

Scientists at the National Centre of Cardiovascular Research in Madrid, Spain, studied 811 patients who were admitted to hospital with heart attacks between 2003 and 2009. 

All had suffered a type of heart attack known as an ST segment elevation myocardial infarction, caused by a prolonged period of blocked blood supply.

The researchers gauged the severity of the attacks by measuring the levels of the enzymes creatine kinase and troponin-I, which are higher the more the heart muscle has been damaged. 

They found that damage to the heart was 21 per cent greater when the attack had occurred between 6am and midday.

The results of the study, published in the medical journal Heart, also revealed that 269 patients had their heart attack in the 6am to noon period, followed by 240 patients who had their attack between noon and 6pm, 161 during the 6pm to midnight period, and 141 between midnight and 6am.

Doctors cannot yet explain why heart attacks appear to be more severe in the morning, but they believe it may be caused by natural changes in the body that occur over a 24-hour period.

For example, blood pressure is at its highest in the morning and lowest at night, during sleep. Hormones such as cortisol, which increases blood sugar levels, are also in higher concentration in the morning. The body’s metabolism increases when we wake up, but at night it is comparatively slow.

The trend could also be explained by the fact some people suffering chest pain at night may try to wait until morning before getting help.

Judy O’Sullivan, senior cardiac nurse at the British Heart Foundation, said: ‘This study provides some interesting observations. However further research is needed.

‘Regardless of the time of day, the quicker someone having a heart attack is treated, the less the damage they will have, which is why it is essential that anyone who experiences heart attack symptoms should call 999 immediately.’ 

There is already compelling evidence that heart attacks are more common in the morning. In 2008 researchers in Cincinnati claimed the risk was four times as high compared with other times of the day.

Photo credit:  TheWondrous

Via Daily Mail