It's Medical Monday!- Why Blood Pressure Climbs in the Winter

Happy Medical Monday, Aortic Hope family! My name is Branden and I'm excited to share my first post as a part of the team. As the days get shorter and the mornings get colder, many of you may notice something on your home blood pressure monitor: the numbers start creeping up. You're not imagining it. Blood pressure really does tend to run higher in the winter, and for anyone living with aortic disease, that's worth paying attention to. Today we'll look at why it happens, how to keep track of it, and a few simple habits that help.

Why Cold Weather Raises Blood Pressure

When you step out into the cold, your body works to hold on to its heat. One way it does this is by narrowing the blood vessels near the skin, a process called vasoconstriction. Narrower vessels mean your heart has to push harder to move the same amount of blood, so your blood pressure goes up.

This isn't a one-day blip. Researchers around the world have found the same seasonal pattern again and again: blood pressure runs lower in warm months and higher in cold ones. A large U.S. study presented at the American Heart Association's 2023 Hypertension Scientific Sessions found that systolic pressure (the top number) averaged up to 1.7 mmHg higher in winter than in summer, and that the share of patients whose blood pressure was under control dropped by up to 5% in winter (source). In some groups, especially older adults, the winter rise is much larger.

A few mmHg may not sound like much. But for those of us living with a repaired or weakened aorta, keeping blood pressure in our target range is one of the most important things we can do, and winter makes that a little harder.

Watch the Trend at Home

The best way to catch a seasonal rise is to check your blood pressure at home, and to do it the same way every time. Small changes in how you measure can move your numbers more than the weather does, so consistency is what makes the trend meaningful:

• Measure at the same times each day, such as morning before medications and again in the evening.

• Sit quietly for 5 minutes first, with your back supported and feet flat on the floor.

• Rest your arm on a table at heart level, with the cuff on bare skin.

• Use the same arm and the same cuff each time.

• Skip caffeine, exercise, and smoking for 30 minutes beforehand.

• Write down every reading, or let your monitor's app keep the log for you.

Our own Ani walked through why this matters in his post on measuring blood pressure correctly. The short version: one reading tells you very little, but weeks of readings taken the same way may tell your doctor a lot.

Bring that log to your appointments, or send it through your patient portal if your numbers start drifting above your target. Blood pressure medicines sometimes need a seasonal adjustment. The European Society of Hypertension notes that a rise in cold weather may simply be seasonal and can justify a change in treatment, while summer can bring the opposite problem of pressure dropping too low (source). Your doctor can only make those adjustments if they can see the trend. Please don't change or skip doses on your own.

Are Aortic Dissections More Common in Winter?

The research says it may! A review that pooled 42 studies and more than 80,000 patients found that acute aortic dissection and rupture were about 17% more likely in winter, with December the peak month (source). Higher winter blood pressure is thought to be a big part of the reason, along with sudden exertion in the cold and winter illnesses like the flu. For a deeper look, read Purab's post on whether more dissections happen in winter and Keyana's post on winter and aortic dissections, which also covers the warning signs to know.

Simple Ways to Stay Steady This Winter

Dress warmly. Layers, a hat, gloves, and a scarf over your nose, and mouth all help your body avoid that sudden squeeze on your blood vessels. Keep your home comfortably warm too, especially first thing in the morning.

Avoid sudden hard effort in the cold. Shoveling heavy snow, pushing a stuck car, or hauling firewood combines cold air with straining, and that can send blood pressure spiking. Ask for help, hire it out, or use a small push shovel and take frequent breaks. Breathe normally and never hold your breath while you lift. If your care team has given you lifting limits, those still apply when it snows.

Watch the salt as the holidays approach. Holiday meals, party snacks, gravy, ham, and restaurant dinners can quietly pile on sodium, which raises blood pressure. The American Heart Association suggests no more than 2,300 mg of sodium a day, and ideally closer to 1,500 mg for most adults. Check labels, use the salt shaker with caution, and fill your plate with vegetables and fruit.

The Bottom Line

We can't change the weather, but we can watch our numbers and make a few small adjustments as the season turns. Check your blood pressure the same way each time, share the trend with your doctor, stay warm, take it easy in the cold, and go light on the salt.

This post is for education and support. It is not a substitute for advice from your own medical team or for care in an emergency. Call 911 if you experience sudden, severe chest, back or abdominal pain, fainting, or other potentially life-threatening symptoms.

Stay warm and look out for each other, Aortic Hope family. See you next Medical Monday!

Take care,

Branden

CUNY School of Medicine