Recent research indicates that an hour of sleep is lost due to the change to daylight savings time increases the threat of heart attacks the subsequent Monday by approximately twenty-five percent compared to other Mondays during the year. In contrast, the risk of heart attack is reduced by twenty-one percent when the clock goes back to standard time and people sleep for an extra hour.

Daylight Savings Time
The database of non-federal Michigan hospitals also points to the influence of moving the clock forward and backward. The hospital observed the frequency of admissions to the hospital before the beginning of daylight savings time and the following Monday for more than four years.

Dr. Amneet Sandhu, a cardiology fellow at the University of Colorado in Denver who conducted the research, discussed his findings at the annual scientific sessions of the American College of Cardiology in Washington. He said that there is a loss of one hour of sleep because of the change to daylight savings time. He also said that heart attacks generally occurred on Monday mornings. The reason might be the pressure of the new working week and an altered sleep cycle due to daylight savings time.

Although a link between sleep deprivation and heart attacks was established in earlier studies, researchers are still unable to find out why people are sensitive to changes in the sleep-wake cycle. Dr. Sandhu says that their study indicates that even the slightest change in sleep may have debilitating effects on the health of an individual.

What Is Daylight Savings Time (DST)?

Usually, the clock is moved forward by one hour in the spring so that there is more daylight in the evenings compared to in the mornings. The time is changed back to normal in the fall. Daylight savings time, or DST, started during World War I to save energy. However, some experts do not agree with this change and they question whether the change in time serves any purpose and whether there is still a need for it.

What’s The Study?

Dr. Sandhu inspected more than forty thousand people who were admitted to the Michigan hospitals. He found that around thirty people suffered a heart attack on any Monday. However, there were eight incidences of heart attacks on the Monday after the shift to daylight savings time. The number of people who had heart attacks on other days of the week was very low.

Dr. Sandhu added that heart patients are at increased risk of a heart attack after changing to daylight savings time. He suggested that hospitals should increase staff numbers on Mondays after the change to daylight savings time. If we are aware of times when there will be an increased number of patients with heart attacks in hospitals, we will be equipped to take care of them.


The researchers concluded that there are numerous limitations to the investigation. The research is limited to one particular area and to the types of heart attack that require artery opening surgeries, such as stents. The research does not involve patients who passed away before being admitted to hospital.

Leave a Reply

Your email address will not be published. Required fields are marked *