Cold weather exposure can increase the risk of cardiac responses, including heart attacks. This is because blood vessels respond to low temperatures by constricting, which increases blood pressure and reduces circulation, putting strain on the heart.

A heart attack, or myocardial infarction, occurs when something creates a blockage in the blood vessels, usually a blood clot, causing a sudden interruption to the blood flowing to the heart. Doctors classify heart attacks as an emergency, as they deprive the body of oxygen and can cause sudden death. It is important to seek immediate medical attention if a person is experiencing heart attack symptoms.

Cold weather increases strain on the heart, as it affects cardiac and circulatory functions. People with existing cardiovascular conditions are at particularly high risk of heart attacks during cold weather. As a result, it is not uncommon for more cases of severe heart problems to occur during winter months and cold spells.

This article discusses how cold weather can influence the risk of heart attacks, other factors that increase this risk, and preventive measures individuals can take.

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A large 2017 study in Sweden investigating the link between different weather conditions and heart attacks found that they were more common on colder days. During colder weather, the heart needs to work harder to keep a person warm. As such, cold weather can affect the heart and cause:

  • a higher heart rate
  • an increase in blood pressure
  • a higher oxygen demand
  • the blood to thicken, which can lead to blood clotting

People with cardiovascular diseases may experience more adverse effects due to cold weather, including high blood pressure and arterial stiffness. All these factors put further strain on the heart, increasing the risk of a heart attack. Additionally, respiratory tract infections are more severe and spread more easily during winter, which, in turn, can trigger a heart attack.

It is important to be able to recognize the signs of a heart attack. If a person experiences one, the sooner they get help, the more likely they are to recover. The severity of heart attacks can differ between people, as some individuals experience severe pain while others only notice slight discomfort.

It is important to seek immediate medical attention if a person thinks they may be experiencing heart attack symptoms. If an individual has the training to use CPR or a defibrillator, they could provide help until emergency medical personnel arrive.

The risk of having a heart attack is higher with a combination of cold weather exposure and a sudden burst of exercise. As such, it is advisable for people to avoid sudden exertion in snowy weather, including shoveling snow or going for a walk through heavy, wet snow.

Risk factors for heart attacks and heart disease can include the following:

  • high blood pressure
  • high blood cholesterol
  • smoking
  • age
  • family history
  • diabetes
  • obesity
  • lack of regular exercise
  • high alcohol consumption
  • consuming a diet high in saturated fats, trans fats, and cholesterol

However, some risk factors may have greater influences on how cold weather affects the condition that the heart is in than others. For example, a 2016 study suggests that smoking status and alcohol consumption were the risk factors most likely to trigger a heart attack in low temperatures. This is because they directly influence vasoconstriction, increasing blood pressure as a result.

There are steps to reduce a person’s chances of having a heart attack during cold spells. To minimize the effect of low temperatures on the heart, individuals should try to reduce the duration and intensity of their exposure to cold weather.

A person can achieve this by:

  • wearing plenty of layers of clothing and a warm hat to maintain body temperature
  • staying out of the wind and avoiding damp areas
  • avoiding or limiting consuming alcoholic beverages when spending time in cold conditions, as they can create a false sense of being warm
  • taking regular breaks from physical activity and avoiding overworking the body
  • going indoors regularly to warm up if spending long periods outdoors

Consuming hot meals and warm drinks are a suitable way of warming up when cold. Additionally, it is important to stay active and participate in exercise indoors when it is cold outside. This is because regular exercise can help delay or prevent cardiovascular diseases from developing.

Other preventive measures relate to minimizing respiratory infection during winter. Pneumococcal and flu vaccines are suitable prevention measures, as they can help reduce the risk of developing cardiovascular complications. Other, more regular, preventive measures include regularly washing hands, avoiding touching the face, and avoiding visiting busy areas.

If a person acquires an infection, they should rest until they have completely recovered before spending time in cold conditions.

A heart attack is a serious health event that usually occurs when a blockage in the blood vessels prevents blood flow to the heart. Cold weather can increase the risk of having one, as low temperatures may put extra strain on the heart.

Other factors can also increase the risk of a heart attack. Some of these, such as vigorous exercise in the cold, can further exacerbate the risk. It is also advisable to dress appropriately, regularly go inside for breaks, and stay warm.

If a person experiences symptoms of a heart attack, an individual should contact emergency services immediately. The sooner someone receives help, the better their chances are of recovery.