As temperatures start to fall, your risk of a heart attack begins to climb. The drop in weather triggers natural rise in blood pressure and cholesterol.

It is believed that the risk of having a heart attack was greatest on days when the temperature was below freezing and there is up to a 31 percent increase in heart attacks in the coldest months of the year compared with the warmest.

Winter weather, studies suggest, may be especially risky for your heart if you’ve already had a heart attack, have heart disease, or are older than 65.

As per Dr. Bhurji, “cold weather sometimes creates a perfect storm of risk factors for cardiovascular problems.” Many of these risks stem from a mismatch between supply and demand.

Cold weather can decrease the supply of oxygen-rich blood to your heart muscle. And it can put you in situations that force your heart to work harder; as a result, your heart demands more oxygen-rich blood. Such a mismatch-a smaller supply of oxygen to the heart coupled with a greater demand for oxygen by the heart-sets you up for a heart attack.

Below, we summarize some of the many situations that can lead to heart attack during the colder months-and how to minimize them.

Risk: Overexertion

Winter sometimes causes us to overexert. We walk briskly against a strong wind, shovel the walk, push a car out of the snow. Exertion increases the heart’s demand for oxygen. “If there’s a blockage in a heart artery that reduces blood flow to the heart muscle, supply may not be sufficient to meet the demand,” Many of us have blockages we don’t know about.

Solution: “Be especially careful about exerting yourself outdoors in winter. Pushing an inch of snow is one thing, but shoveling heavy, wet, deep snowfall is very risky. I encourage my patients to avoid doing so, especially if they have risk factors for heart disease,” Risk factors include smoking, high blood pressure, high cholesterol, diabetes, family history, and obesity. It is better to have someone else shovel snow for you.

Risk: Cold exposure

When your body is suddenly exposed to icy temperatures, your blood vessels clamp down.

Solution: “Don’t head out the door half-dressed. Put on your coat, hat, and gloves in advance.”

Risk: Overheating

While it’s important to dress warmly in cold weather, it’s also important to avoid getting overheated—for example, from physical activity. If you get overheated, your body will need to release the heat. Too much warm clothing may prevent that, causing blood vessels to dilate, which can dramatically lower blood pressure. “When blood pressure drops, it can reduce the heart’s blood supply, possibly leading to a heart attack.”

Solution: Dress in layers. If you start to sweat, remove a layer until you cool down, then replace the layer. Better yet, go inside and take a break.

Risk: Influenza

About of seasonal flu can trigger a heart attack in people already at risk for heart disease. The flu causes a fever, which makes your heart beat faster (raising its demand for oxygen). The flu also can cause dehydration, which can reduce your blood pressure (lowering the heart’s supply of oxygen). “Again, when demand exceeds supply, it may lead to a heart attack.

Solution: Try to avoid getting the flu by washing your hands often with soap and water and getting a flu shot. If you do get flu symptoms, such as fever, cough, or body aches, call your doctor Avoid dehydration by drinking plenty of fluids or eating water-rich foods such as fruit or soup.

Risk: Missed prescriptions

Snowy or icy weather can keep you from following through on your doctor visits or getting your prescriptions filled on time. “If you haven’t had your medications, and blood pressure is not adequately controlled, it can increase heart attack risk.”

Solution: In winter months, it’s best to have a supply of medication large enough so that you won’t run out if there’s rough weather. “Not waiting until the last minute to fill prescriptions is another wise move, especially if the weather can make transportation a problem.”

Dr. Pargat Singh Bhurji
MD,FRCP ( C ) Consultant Pediatrician Surrery BC