The cold of winter can endanger our heart health. Some physicians actually refer to this time of year as “heart attack season.”
Some estimates indicate that 53% more heart attacks happen in the winter than during the summer months. WebMD notes that the American Heart Association observed the rate of heart disease-related deaths increases sharply between Dec. 25 and Jan. 7, peaking on Christmas Day and New Year’s Day.
There are many theories circulating about why this occurs. Stephen P. Glasser, M.D., a professor of preventive medicine at the University of Alabama at Birmingham School of Medicine, told WebMD that this spike may be related to the “change in the ratio of daylight hours to dark hours, which changes the hormonal balance, and the hormones involved, such as cortisol, can lower the threshold for a cardiovascular event.”
Dr. Glasser adds that research has shown that wintertime heart-related incidents occur more frequently in the morning hours, which is linked to an early-morning rise in blood pressure:
In the winter, people tend to exert themselves or do yard work in the morning because it gets dark earlier … This shift of activities to morning hours adds to the normal circadian variation in mornings — further increasing heart rate, blood pressure, and the hormones that lower the threshold for a cardiovascular event.
Sid Kirchheimer, writing in the AARP Bulletin, says winter’s heart dangers are primarily the result of colder temperatures. The body typically compensates for the cold by constricting the arteries, increasing blood pressure and, eventually, making the heart work harder.
Dr. Holly Andersen, director of education and outreach at the Ronald O. Perelman Heart Institute of NewYork-Presbyterian Hospital/Weill Cornell Medical Center, explains:
When the temperature outside drops, our blood vessels narrow to prevent our bodies from losing heat. This is a natural response that can also put people with heart conditions and those involved in strenuous exercise at greater risk of having a heart attack.
Those constricting arteries can cause tears or splits in the plaque lining the arteries, which can form blood clots. The blood clots can trigger a heart attack or stroke, both of which also occur more frequently during winter.
Some researchers have linked an increased incidence of heart attack or stroke — among other ailments commonly associated with aging — to vitamin D deficiency. Although physicians estimate that all you need to maintain a healthy level of vitamin D is about 15 minutes of sun on your arms each day, it’s difficult in the shorter winter months to get a sufficient supply of sun. Also, some older people may need vitamin D supplements to maintain optimal heart health. Consult a physician regarding individual supplementation needs.
Although there can be numerous factors that can contribute to winter illnesses, shoveling snow remains among the most strenuous and dangerous winter exercise activities precisely because it can raise blood pressure. Some typically sedentary individuals may feel compelled to clear their driveway when the first snows fall, not realizing that this is a real workout. The danger can be compounded if a heart attack is mistaken for a pulled muscle and treatment delayed.
Coupled with the other effects of colder temperatures on the body, shoveling snow can increase heart-attack risk dramatically.
Dr. Andersen offers the following tips to help you safely shovel snow:
- Warm up. Warm up with stretching and light activity before shoveling, exercising, or beginning more strenuous physical activities.
- Bundle up. When going out to shovel, always wear a scarf over your mouth and nose to warm the air before you breathe in, and dress in layers. Layering clothes underneath a windproof and waterproof outer shell helps maintain body heat.
- Push the shovel. It is less strenuous to push the snow rather than lifting it, and this reduces the risk of overexerting yourself.
- Take breaks. You should take frequent breaks while shoveling to give your muscles, especially your heart muscle, a chance to relax. You may also consider sharing the work with a friend to make the workload lighter and ensure that you are not alone in the event of an emergency.
If you are over the age of 50, overweight, out of shape, or have previously suffered a heart attack — consult a doctor before shoveling snow or starting any exercise routine.
Image by wunluv (Santhan Naidoo), used under its Creative Commons license.
