Why Does the Risk of Heart Problems Increase During Winter

Winter weather can be deadly—for your heart.

This is the conclusion of several studies that investigated the impact of cold weather on the heart. One study published in the journal Hypertension examined the effects of weather (sunlight, air temperature, and rain) on 16,010 people with high blood pressure. This study found that blood pressure increased as the outdoor temperature dropped.

Another study published in PLOS One investigated seasonal variations in blood cells in 27,478 children and 36,644 adults. These researchers found more white blood cells and fewer red blood cells present in the winter compared to the summer months. These results suggest the body may reduce the amount of oxygen transported to cells in the winter-spring months while it prepares itself to fight infections. This may be one reason a higher number of cardiovascular events are reported in the winter.

Our physiological responses to cold weather may also help explain the increased risk of heart problems. Cold temperatures activate your sympathetic nervous system, which causes your blood vessels to narrow, resulting in cold-induced high blood pressure. Elevated blood pressure puts you at greater risk for heart disease, especially combined with winter sports, shoveling or walking in the snow.

Narrowed blood vessels decrease the amount of blood that flows through your blood vessels, and less oxygen and nutrients reach your tissues. In response to narrowed blood vessels, your heart increases your heart rate to provide more blood, oxygen and nutrients to your body. If you have fewer red blood cells, your heart may need to work even harder to provide the same amount of oxygen and nutrients to your cells.

The best way to protect yourself from heart-related complications in the winter is to stay warm and alert. Wear layers of clothing to keep your body warm, reduce blood vessel constriction and maintain a healthy blood pressure. Maintaining healthy blood pressure is important for the health of your blood vessels and heart. High blood pressure can damage and weaken your blood vessels and increase your risk of heart attack or stroke.

Stay attuned to how you feel in cold weather, especially when engaging in physical activity. If you detect any irregularities, respond to them by calling your doctor or cardiologist.

Next Steps:

• Read the original article about Blood Pressure Response to Patterns of Weather Fluctuations and Effect on Mortality
• Read the original article entitled Seasonal Variations of Compete Blood Count and Inflammatory Biomarkers in the US Population-Anaylsis of NHANES Data