man holding chest due to heart attack
Julie Hambleton
Julie Hambleton
February 12, 2024 ·  4 min read

Heart Attacks Are Most Common On This Day Of The Week, Study Finds

Heart attacks are scary and can quite often be deadly. For those with a greater risk of having one, this newly published research will give yet another reason to have the “Sunday Scaries.” A recent study conducted by doctors at the Belfast Health and Social Care Trust and the Royal College of Surgeons has found that deadly heart attacks are most likely to occur on everyone’s favorite day of the week, Mondays.

Study Finds Deadly Heart Attack Most Likely to Occur On Mondays

As if Mondays weren’t already bad enough. Now, research shows that if you’re at risk of a heart attack, Monday is the most likely day of the week you’ll have one on. The study analyzed data from 10,528 patients from the Republic of Ireland and Northern Ireland admitted to hospitals between 2013 and 2018 with an ST-segment elevation myocardial infarction (STEMI). This is not the first study to find this, and past research teams have dubbed this ever-dreaded day of the week “Blue Mondays.” Previous research points to an association with our circadian rhythms, or the body’s sleep and wake cycle, as a reason for this phenomenon. (1, 2)

What is a STEMI Heart Attack?

STEMI is a type of heart attack that occurs when a complete blockage of one of the heart’s major arteries is blocked. This type of heart attack is considered the most serious and requires immediate medical attention. The study found a significant increase in rates of STEMI heart attacks at the start of the working week, with rates highest on a Monday. There were also higher rates of STEMI than they expected to see on a Sunday. 

The study encompassed patients from both the Republic of Ireland and Northern Ireland, with 7,112 patients from the Republic and 3,416 from Northern Ireland. The data was collected from hospitals across Ireland, including major urban centers and rural hospitals.

Read: Eating chilies cuts risk of death from heart attack and stroke, study says

The Question is: Why?

Truthfully, the researchers aren’t sure why the spike is so significant on Mondays for deadly heart attacks. They hypothesize that this likely has many reasons behind it and caution against pointing to any one cause. That being said, they agree that previous thoughts about circadian rhythm are likely at play.

“We’ve found a strong statistical correlation between the start of the working week and the incidence of STEMI. This has been described before but remains a curiosity. The cause is likely multifactorial, however, based on what we know from previous studies, it is reasonable to presume a circadian element.”  said study lead Dr Jack Laffan.

This refers to the fact that most people generally have a regular weekly routine. We go to bed around the same time each night, wake up at the same time, and follow the same daily routines, more or less. When the weekend arrives, however, we may stay up later and/or sleep in later. We are also more likely to participate in other activities that are different from what we do during the week and eat and drink differently. It is more likely that we eat less heart-healthy foods as well as consume more alcohol. These all contribute to an increased risk of having a heart attack.

Of course, it’s easy to point to Mondays as having a higher heart attack risk because it is the first day of the work week. Many people feel dread or an increased amount of stress on a Monday. While stress can increase your risk of heart attack, the researchers seem to believe that the interruption of our circadian rhythm caused by the weekend is more likely the primary factor at play here.

Read: Did you know that eating heavy meals can trigger heart attacks?

What Does This Mean For Health Care?

The study’s findings have significant implications for healthcare providers and policymakers in Ireland and potentially around the world. The researcher indicates that hospitals should focus on ensuring adequate staffing and resources are available on Mondays to provide timely and effective treatment for patients with STEMI. Additionally, policymakers may need to consider implementing public health campaigns to raise awareness about the increased risk of heart attacks on Mondays and encourage individuals to take preventative measures.

The Bottom Line

While the study’s findings are concerning, it is important to note that individuals can take steps to reduce their risk of heart attack. These include maintaining a healthy diet, engaging in regular physical activity, quitting smoking, and managing stress levels. If you have a low risk of heart attack, then the chances of you having one are not high, no matter what day of the week it is. If you are concerned about your level of heart attack risk, speak with your healthcare provider to have your heart checked and implement a heart health action plan.

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  1. Deadly heart attacks more common on a Monday .” Eurekalert. June 4, 2023.
  2. Weekends rule: Study finds heart attacks more frequent on Mondays.” Study Finds. July 6, 2017.