Cold weather can pose unique risks for cardiovascular health, including an increased risk of having a heart attack according to a recent study published in the Journal of the American College of Cardiology.
The population-based study included over 120,000 heart attack cases that occurred during the cold season in Sweden. For each case, the daily mean air temperature was estimated using a machine learning algorithm. Cold spells were defined as at least two days in a row during which the daily mean temperature was below the 10th percentile of the temperature distribution for a given area. These temperatures and cold spell periods were studied alongside the distribution of heart attack cases to determine whether colder temperatures were linked to a greater risk of being hospitalized for a heart attack.
The results showed that cold spells were significantly associated with higher odds of being hospitalized due to a heart attack. Specifically, lower air temperatures during the cold season were associated with about 10% higher likelihood of being hospitalized due to a heart attack, and cold spells lasting two or more days were associated with an additional 8% increase in risk.
Specialists in cardiology note that cold weather affects the heart through several mechanisms. Cold weather generally increases blood pressure and slightly increases heart rate. It also triggers a stress response and the release of adrenaline. It can raise blood pressure to a greater degree than usual during exercise, which increases the workload on the heart. In combination, these effects can pose a danger to people with heart disease.
To make exercise safer for the heart during cold weather, it’s important to wear proper clothing to keep your body temperature up. Additionally, alcohol should be avoided during cold weather since it can further decrease body temperature while also raising blood pressure. For people who are at particularly high risk, such as those with preexisting cardiovascular disease, it’s best to avoid exercise during cold weather and to avoid exposure to extreme cold.
Sources: Journal of the American College of Cardiology, Medscape
