Does unusual weather increase the risk of stroke?

According to Associate Professor, Doctor Nguyen Huy Thang, Chairman of the Ho Chi Minh City Stroke Association, weather that is too cold or too hot, especially combined with a humid climate, can affect the risk of stroke.

When the weather is too hot, the body loses a lot of water, easily creating blood clots in the blood vessels, especially the venous system. This risk is higher when we are exposed directly to sunlight for a long time or when the body temperature exceeds 40 degrees Celsius.

On the contrary, when the weather is too cold, we often do not drink enough water, dehydration can also lead to blood clots.

"In most cases, the weather may be a contributing factor rather than a direct cause of stroke. Except when the body temperature is above 40 degrees Celsius, the patient may have a stroke due to hyperthermia," Dr. Thang shared.

Doctor Nguyen Huy Thang examines a patient. Photo: BSCC

He analyzed that weather that is too cold or too hot can affect the blood vessel system, causing excessive dilation, increasing blood pressure and increasing heart activity. This risk is more serious for elderly patients with underlying diseases such as high blood pressure that are not well controlled.

Recently, several studies have shown a link between weather and stroke. At the European Society of Cardiology 2022 conference, doctors presented a study conducted in Japan with 3,367 residents over 65 years old, in Okayama city.

According to this study, the association with stroke is most evident in the month after the rainy season. For every 1 degree Celsius increase, the risk of hemorrhagic stroke increases by 24%, and the risk of ischemic stroke increases by 36%.

Another study conducted in eight cities in China with a population of 48 million people, cold season temperatures ranged from 4-23 degrees Celsius and hot season temperatures from 28-34 degrees Celsius.

The results showed that both extremely cold and extremely hot weather can increase the risk of stroke. The impact of cold weather is in the first 2 weeks, the impact of hot weather is in the first 3 days of exposure. Thus, the time of climate change is the time of high risk. The risk gradually decreases after that as the body has time to adapt.

However, these studies are all retrospective and many confounding factors have not been taken into account. In Vietnam, there has been no research conducted to assess the impact of weather on stroke.

According to Vietnamnet