- About 1.28 billion adults worldwide have high blood pressure, or hypertension.
- Medications and various lifestyle changes are common treatments for hypertension.
- New research presented at a recent American Heart Association conference found that blood pressure increases in the winter compared to the summer months.
- Researchers say seasonal variation in blood pressure may require additional physician monitoring and changes to medications or lifestyle changes.
Researchers believe these seasonal variations in blood pressure may require more physician monitoring and treatment modifications.
Previous studies have shown there is a
Generally speaking, blood pressure
“One of the main ways in which blood pressure gets regulated in the body is the arteries either clamping down or loosening up — we call that
“If it’s cold outside, you become vasoconstrictive, so the arteries tighten up and the blood pressure goes higher. If you feel hot, then the blood vessels dilate and you get vasodilation that can cool the body down,” Dr. Ni explained for Medical News Today.
A study in April 2021 found that just increasing a room’s temperature by
For this study, researchers reviewed electronic health records for over 60,000 adults treated for high blood pressure between July 2018 and June 2023 at six healthcare centers.
Study participants were an average of 62 years old. More than half identified as Caucasian and about 60% identified as female.
When analyzing seasonal blood pressure readings, scientists found that, on average, a study participant’s systolic blood pressure rose by up to 1.7 mm Hg in the winter months compared to the summer months.
Additionally, researchers found that participant
“The findings supported the existence of seasonal variation in blood pressure, which has been noted in previous studies,”
“Despite the smaller degree of systolic blood pressure variation, we were surprised to observe a great degree of change in blood pressure control between winter and summer months. Additionally, [the] temperate season was indicated as a significant predictor of visit control — a feature which has not been extensively described before.”
– Robert B. Barrett, lead study author
Because people with high blood pressure are less likely to have their blood pressure controlled in winter compared to summer, Barrett said more physician and lifestyle interventions may be necessary.
“Seasonal variation in blood pressure has a substantial effect on hypertension control, often defined as blood pressure <140/<90,” he continued.
“If the blood pressure is very well controlled, for example to <130/<80, then seasonal variation will have little effect on control to <140/<90.”
“However, if blood pressure is not well controlled, then patients near the 140/90 level could benefit from monitoring their blood pressure regularly, closer medical follow-up, and avoiding decreased physical activity and increased weight toward year-end,” Barrett added. “Some patients may benefit from increased pharmacological intervention to keep blood pressure controlled during the winter.”
After reviewing this study, Dr. Cheng-Han Chen, interventional cardiologist and medical director of the Structural Heart Program at MemorialCare Saddleback Medical Center in Laguna Hills, CA, not involved in the research, told MNT that, while these findings add previous studies looking at seasonal variation and high blood pressure, this study is significant due to the large and varied participant pool.
“This study is important for informing physicians on how tightly we have to monitor a patient’s blood pressure, depending on the season,” he continued.
“For instance, this tells us that we should pay extra attention to having accurate measurements during the winter months, as we may need to adjust the medications during this time to get the blood pressure under control.”
“The next step [in this research] would probably be some sort of either public outreach or physician education on this type of effect,” Dr. Chen added.
“I think most of us are not really too aware of this cold weather effect on blood pressure. A lot more physician education on the importance of blood pressure controls, specifically during the colder winter months, [would] help patients,” he admitted.
Dr. Ni agreed that the findings were not surprising, but said it is good to have a study on this topic as there still remain questions on how weather affects blood pressure.
“And it does seem to be a fairly significant amount — a couple points of blood pressure doesn’t seem like much, but it definitely adds up over time,” he continued.
“It’s really more about understanding what other environmental factors contribute to blood pressure — I think that’s where the next steps need to be,” Dr. Ni added. “We have to have greater awareness of how day-to-day activities and day-to-day exposures for people living their normal lives might impact health factors that contribute to cardiovascular disease.”
Blood pressure measures the amount of pressure placed against the walls of the arteries as blood flows through them.
A person’s blood pressure measurement is comprised of two different numbers:
- the top number is the
systolic blood pressure, measuring the maximum pressure in the arteries when a person’s heart beats or contracts
- the bottom number is the
diastolic blood pressure, measuring the lowest pressure in the arteries while the heart is relaxed.
Blood pressure is measured in millimeters of mercury (mm Hg).
Blood pressure is
High blood pressure can sometimes occur without any symptoms, which is why it is important to have your blood pressure regularly checked.
Although the main cause of hypertension is still unknown, past research does show certain factors can increase a person’s risk for developing high blood pressure such as
People with high blood pressure are also at an increased risk for developing other diseases, including: