Cold Weather—More Heart Attacks
As winter approaches, most of us are doing our best to adjust to earlier nightfall and dropping temperatures. It can be hard to get motivated to do much of anything when it is so cold outside. And now, there is another reason to dislike the windy, wintry weather that will soon be upon us. New research suggests that falling mercury could mean trouble for your heart.
The study, which took place at Lund University in Sweden, found that weather conditions that include low temperatures and strong winds are associated with an increase in heart attacks.1 These results are based on the medical records of 274,029 adults living in Sweden who had experienced a heart attack at some point from 1998 through 2013. The subjects had a mean age of 71.7. The investigators analyzed detailed weather conditions on the day of each participant’s heart attack to determine whether there were patterns occurring.
The most pronounced impact on heart attack risk came from colder air temperatures, with the likelihood of experiencing a heart attack rising when the mercury falls below 32 degrees Fahrenheit. And for every 13 degree F increase in air temperature, the risk of heart attack dropped approximately three percent. But temperature wasn’t the only factor at play. Strong winds, a short duration of sunshine, and low atmospheric pressure were also shown to be associated with a greater risk of heart attack.
Although it is not clear exactly why the cold, brisk weather might contribute to more heart attacks, the researchers theorize that it may produce changes in the circulatory system that set the stage for problems in some people. Cold temperatures and high winds can both produce reactions that include the contraction of blood vessels near the skin, which is a mechanism that helps the body to maintain its core temperature. But as the blood vessels contract, there is greater resistance in the blood flow throughout the body, making the heart need to pump harder and potentially creating enough stress to be the trigger for a heart attack, particularly in older people and those already at risk.
A lack of sunlight can also affect our bodies more than you might realize. Sun exposure is necessary for internal production of vitamin D. If we are not getting adequate amounts of time in the sun our vitamin D levels drop, increasing the likelihood of developing hypertension, which is a major risk factor for heart attacks. A 2014 study at the University of Southampton in the United Kingdom showed that exposure to sunlight reduces blood pressure, slashing the risk of both heart attacks and stroke.2
Keep in mind, however, that the current study was not designed to prove cause and effect, so we only know there appears to be a link between weather factors and heart attacks. Plus, we need to consider that the only information we have on the participants is that they experienced a heart attack. Any possible influencing factors, such as being overweight and having a sedentary lifestyle, might be compounded in the cold weather due to stress or exertion from, for example, needing to shovel the driveway.
So, what’s a person to do if you live in an area that typically experiences cold weather in the winter? Besides packing up and spending the next few months in a tropical locale (which sounds appealing but probably isn’t realistic for most of us), there are some precautions you can take. Plan ahead when you know the temperature will soon be dropping so you are prepared with warm clothing, coats, gloves, and hats—since between seven and 10 percent of body heat is lost through the head.
And work on reducing your other risk factors for heart attacks all year long. That means eating nutritiously and maintaining a healthy weight, exercising regularly, and learning strategies to deal with stress such as mindfulness meditation and natural herbal remedies that contain ingredients such as St. John’s wort and ginkgo. If you lower your chances of developing cardiovascular disease, you’ll be ready to take on the cold weather and stay healthy this winter.
- 1. Mohammad, Moman A.; et al. "Association of Weather With Day-to-Day Incidence of Myocardial Infarction." JAMA Cardiology. 24 October 2018. Accessed 28 October 2018. https://jamanetwork.com/journals/jamacardiology/fullarticle/2706610.
- 2. Liu, Donald; et al. "UVA Irradiation of Human Skin Vasodilates Arterial Vasculature and Lowers Blood Pressure Independently of Nitric Oxide Synthase." Journal of Investigative Dermatology. July 2014. Accessed 29 October 2018. https://www.jidonline.org/article/S0022-202X(15)36878-0/fulltext.