As winter kicks into gear, people with heart disease need to be particularly on alert. Lower temperatures raise health risks for people prone to heart problems, according to the American Heart Association; a recent study found that a temperature drop of 1.8 degrees Fahrenheit means 200 additional heart attacks. Both cold weather itself and other weather conditions that accompany it—heavy, wet snow, particularly—can require more of the heart than usual. Moreover, regardless of the temperature, the longer nights and shorter days affect hormones and make heart attacks more likely.
Often, cold-weather heart failure is triggered by hypothermia. When people are too cold for too long, the body temperature falls below 95 degrees Fahrenheit and hypothermia sets in. The efficient cooling of wind means hypothermia sets in faster—wind chill isn’t just about comfort, it reflects how fast your body temperature will fall to dangerous levels. To keep the body warm, the heart pumps more. That means your blood pressure goes up, a serious danger for people who already experience chronic hypertension. The cold also makes the blood thicker and blood vessels narrower, another reason for higher blood pressure and a risk factor in and of itself for a heart attack or stroke. In addition, the heart requires more oxygen when the body is cold, meaning it’s easy to suddenly become short of breath.
Respiratory infections common in cold weather put extra stress on the heart. The flu shot needs to be administered every year, but if you have coronary artery disease, it could save your life. Flu and other ailments are known to be connected to heart health. Avoiding crowds, staying away from people with colds, and washing your hands after using the bathroom, before eating, and when coming in from outdoors or after using public transportation can help you avoid infection. If you do get sick and you have high blood pressure, read warnings on medications carefully.
One indirect way cold weather affects the heart is snow. Shoveling snow involves a lot of heavy lifting and exertion, more than is a part of most people’s daily activities most of the year. The strain this puts on the heart causes heart attacks every winter. Even walking through heavy, wet snow can create extra strain. People who start exercising in January—a common New Year’s resolution—need to be careful to start slowly and not attempt to do too much too soon, or they, too, put their hearts at risk. That doesn’t mean don’t exercise at all, but talk to your doctor about what’s safe.