It's Topic Tuesday!

Do More Aortic Dissections Happen in the Winter?

During the winter, clinicians have often sensed that more patients present to the emergency department with aortic dissections. Is this just a coincidence, or do more dissections happen in cold weather?

It’s a fair question. Many heart-related conditions, like heart attacks and strokes, show seasonal patterns. But what about the aorta? According to large international studies and several meta-analyses, the answer is clear: yes, more aortic dissections occur in the winter months than in any other season.

What the Research Shows

Researchers have consistently found that aortic dissections are most common in December and January, and least common in the summer.

This pattern appears everywhere from North America and Europe to Asia, and it affects both Type A and Type B dissections. Even in warmer regions, where temperatures rarely drop below freezing, there is still a noticeable rise in cases during the winter.

This tells us that it isn’t just about climate: it’s about how our bodies respond to colder weather and the physiological changes that come with it.

Why the Winter Months Matter

Researchers believe several factors work together to explain this seasonal increase.

1. Cold weather raises blood pressure.

When you’re exposed to the cold, your blood vessels naturally narrow to conserve body heat. This tightening increases blood pressure, putting extra stress on the walls of your arteries, including the aorta. For someone with a weakened or surgically repaired aorta, these spikes in pressure can become clinically significant.

2. Sudden temperature changes can trigger strain.

It’s not only the cold itself that matters, but also the rapid drops in temperature from one day to the next. These swings can cause sudden changes in blood pressure and heart rate, increasing the risk of dissection.

3. Winter infections and inflammation.

During flu season, the body experiences higher levels of inflammation and stress. Studies have shown that hospital admissions and mortality for acute aortic dissection are higher during influenza outbreaks. Illness can raise heart rate, blood pressure, and vascular stress.

4. Lifestyle and seasonal habits.

In winter, people tend to be less active, eat more salty or heavy foods, and experience greater stress around the holidays. All of these can raise blood pressure and contribute to vascular strain.

5. Physical exertion in the cold.

Activities like shoveling snow can cause sudden increases in blood pressure, especially when combined with cold exposure or breath-holding during exertion. These situations are known triggers for cardiovascular events.

What You Can Do

The takeaway isn’t to avoid winter altogether; it's to be mindful of the phenomenon and the mechanisms behind it. If you have an aortic aneurysm, have undergone aortic surgery, or are being monitored for aortic disease, you can lower your risk with a few simple habits:

• Monitor your blood pressure regularly. Check at home and record your readings, especially when temperatures change.

• Take your medications as prescribed. Avoid skipping doses, even during holidays or travel.

• Avoid sudden strain. Breathe normally when lifting or shoveling, and avoid holding your breath or pushing to exhaustion.

• Dress warmly. Keeping your body temperature stable prevents your blood vessels from tightening suddenly.

• Stay healthy during flu season. Get your flu shot, wash your hands often, and rest if you’re sick.

• Maintain a routine. Eat balanced meals, limit salt, and stay active when possible.

The Bottom Line

Yes, aortic dissections are more common in the winter. While you can’t change the weather nor avoid the winter forever, the most important factors remain in your control.

Thanks everyone, please join us again for another Topic Tuesday next week!

-Purab