Why Daylight Saving Time Could Increase Your Heart Attack Risk

The number of heart attacks rises the Monday after daylight saving time, a Michigan Medicine study found. Interrupted sleep may be the culprit.

7:00 AM

Author | Michigan Medicine

Heart attacks occur most often on Monday mornings. And on one particular Monday, the risk may be further elevated.

Research shows a 24 percent jump in the number of heart attacks occurring the Monday after we "spring forward" for daylight saving time compared with other Mondays throughout the year.

That lost hour of sleep may play a bigger, perhaps more dangerous role in our body's natural rhythm, according to a 2014 study led by the University of Michigan Frankel Cardiovascular Center.

Although researchers can't say precisely what is driving this rise in heart attacks, they have a theory.

The reason more heart attacks happen on Monday mornings could be attributed to several factors, including the stress of starting a new workweek and inherent changes in our sleep-wake cycle. Previous studies have linked poor or insufficient sleep with heart disease.

With daylight saving time, all of this is compounded by one less hour of sleep.

A night-and-day difference

The hospitals included in the study admitted an average of 31 patients having a heart attack on any given Monday.

But the Monday immediately after springing ahead, there were an average of eight additional heart attacks. Cardiac events tapered off over the other days of that week.

Perhaps more telling, researchers found a 21 percent drop in the number of heart attacks the Tuesday after returning to standard time in the fall, when we gain an hour back.

The study has limitations. For example, it was restricted to one state and heart attacks requiring treatment such as angioplasty, therefore excluding patients who died before they got to the hospital or received help.

SEE ALSO: How Chronic Snoring Can Cause Heart Disease

Still, the findings may underscore a need to better staff hospitals the Monday after setting our clocks forward. It may also mean people who are vulnerable to heart disease may be at greater risk after sudden time changes.

Other risk factors

Although we can't change the calendar, preventive steps can be taken.

Give your body time to adjust by going to bed and waking up 15 minutes earlier starting two to three days before the time change (get more daylight saving time sleep tips from a Michigan Medicine physician here).

It's also helpful to know the signs and symptoms of a heart attack, no matter the time of year.

Crucial, too, is a commitment to making healthful choices.

After all, "most heart attacks happen in those who smoke or have risk factors that are not controlled," says Michigan Medicine cardiologist Hitinder Gurm, M.D. "Quitting smoking would be the most effective strategy for heart attack prevention.

"Controlling high blood pressure and high cholesterol, following a heart-healthy diet and getting regular exercise are other ways to reduce your risk of a heart attack."


More Articles About:

Heart Health Sleep Study Heart Attack Risk Factors Sleep Disorders
Health Lab word mark overlaying blue cells

Health Lab

Explore a variety of health care news & stories by visiting the Health Lab home page for more articles.

Media Contact

University Hospital at U-M Health in the spring with flowering trees in foreground and Survival Flight helicopter visible

Public Relations

Department of Communication at Michigan Medicine

[email protected]

734-764-2220

Stay Informed

Want top health & research news weekly? Sign up for Health Lab’s newsletters today!

Subscribe

Featured News & Stories

A woman wearing a bright yellow sweater is sleeping on her side on a couch. Her mouth is open and her glasses are askew. Her fingers are resting on an open book.
Medicine at Michigan

Why you might be having sleep problems

Excerpt from a book about why you might be having sleep problems.
mother with four kids smiling
Health Lab

A heart attack 9 days after giving birth: Mother of 4 shares her SCAD experience

A mother of four shares journey with a rare heart attack just days after birth called Spontaneous Coronary Artery Dissection, a leading cause of heart attacks in women under 50.
newborn close up in clear bassinet
Health Lab

Half of newborns with severe spina bifida have trouble breathing during sleep

Many infants with the most severe form of spina bifida called myelomeningocele experience breathing disruptions during sleep — increasing the risk of cognitive deficits later in life, a new study finds.
baby on blanket saying little blessing
Health Lab

Specialized local care gives baby with severe heart condition a stronger start before surgery

Newborn with a complex congenital heart defect receives coordinated, specialty care close to home while gaining strength before surgery.
two doctors with patient listening to heart
Health Lab

2 heartbeats, 1 future: Why pregnancy is a critical window for women’s heart health

Cardiovascular disease is the number one cause of death in women. Yet one of the most important windows to understand a woman’s lifelong heart health may come decades earlier during pregnancy. How new research could change heart care for women long after delivery.
Health Lab

How to use an AED in a cardiac emergency

A step-by-step guide on how to use an automated external defibrillator, or AED in a cardiac arrest or emergency