June 18, 2024 – High cholesterol, High blood pressure, Heart disease – most individuals know that these conditions can increase the chance of stroke. But a lesser-known risk factor may also play a task: high outdoor and indoor temperatures.
A newly published study A study by German researchers found that 7% of patients hospitalized for stroke experienced symptoms on a warm night. The temperature threshold for warm air was only 14.6 °C (58 °F) between May and October annually for 15 years.
Our body temperature is kept constant by a process that circadian thermoregulationThis is said to circadian rhythmor the 24-hour clock in our brain that controls sleep-wake cycles. Researchers found that when this process is disrupted by excessive heatA nocturnal stroke can possibly be triggered in two ways.
Blood pressure fluctuations are the primary factor, said the study’s co-author Cheng He, PhDPostdoctoral fellow on the Helmholtz Center Munich, a health and environmental research center in Germany. “Blood pressure naturally drops at night. If our circadian rhythm is disrupted, this drop may not occur as expected, potentially increasing the risk of stroke due to increased nighttime blood pressure.”
Secondly, by the temperature.
“The body cools itself during sleep, a process controlled by the internal clock. Disruption of this rhythm can impair the ability to lower body temperature, potentially leading to sleep disturbances and increased blood viscosity, both of which are risk factors for stroke,” he said.
A new Chinese study It was also found that individuals exposed to high temperatures for only one hour (peak temperature 33°C) increased their risk of stroke as much as 10 hours later, even in the event that they had moved to a spot with lower temperatures. Interestingly, each blood and bacteria within the body may play a vital role in why that is the case.
“When the temperature rises, your body sends more blood to your skin to cool it and make you sweat. This can lead to dehydration, which thickens the blood and facilitates the formation of blood clots that can block blood flow to the brain and cause a stroke,” said the study co-author. Jing Zhao, MD, PhDdeputy director of neurology at Fudan University and chief of neurology at Minhang Hospital of Fudan University in Shanghai, China. “In addition, heat can make the intestinal lining more permeable, allowing bacteria to enter the bloodstream. These bacteria release toxins that cause inflammation throughout the body, which can also contribute to strokes by making arterial plaques unstable.”
Who is most vulnerable to heat-related stroke?
This is most probably to occur in individuals with a condition that increases the possibility of blood clots. In the Chinese study, the chance was particularly high in patients with atrial fibrillation, a condition through which the guts beats irregularly, Zhao said. An irregular heartbeat can mean that Blood cannot be pumped well from your heartwhich ends up in the formation of blood clots.
“Blood clots cause 90% of all strokes,” said Mingming Ning, MD, MMSCDirector of the Cardio-Neurology Clinic at Massachusetts General Hospital in Boston and Associate Professor of Neurology at Harvard Medical School.
Two other conditions may also increase the possibility of a blood clot and make a heat-related stroke more likely. The first is a hole in the guts, also referred to as a patent foramen ovale or PFO.
“One in four people has a PFO,” Ning said. A PFO is a hole within the wall between the left and right atria of the guts. It often closes after birth, and even when it doesn't, it causes no symptoms in any respect in most individuals. However, “if a clot forms in another part of your body, such as your leg, that clot can travel up to your heart,” Ning said. The pressure in your heart changes, and if you will have a PFO, that pressure, combined with the open hole, allows blood to flow from the proper atrium to the left atrium. That flow could carry the blood clot to your brain and cause a stroke.
The kind of clot that causes that is deep vein thrombosis (DVT)DVT often occurs if you sit for long periods of time, corresponding to if you take long automotive rides or fly and sit in a decent airplane seat where you possibly can't stretch your legs.
Ning said 10% of healthy travelers get a blood clot while flying or on an extended automotive ride.
“It's very important to get up and stretch your legs as often as possible on the plane or to stop and get out of the car frequently,” she said.
The risk of DVT is higher when you are obese, over 60, have a bleeding disorder, or are taking contraception pills or hormone substitute therapy medications. Symptoms of DVT may include pain, redness, or swelling in your leg. Sometimes there aren't any symptoms in any respect, so preventative measure is Wear compression stockings when travellingCompression stockings stop swelling and direct blood flow back to the guts, helping to stop deep vein thrombosis.
How are you able to prevent a stroke in hot weather?
1. Make sure you drink enough fluids.
“Water is the cheapest blood thinner you can buy,” said Ning. “If your blood is not sufficiently hydrated, your platelets will clump together.” Men should aim at about 15.5 cups (3.7 liters) per day, and girls should aim to drink about 11.5 cups (2.7 liters) per day. Drink much more in hot weather.
2. Get a medical examination.
Through a physical examination, your doctor can determine if you will have a medical condition which will increase your risk of stroke when your temperature rises.
“Monitoring and treating underlying health conditions such as high blood pressure [high blood pressure]Dyslipidemia [abnormal levels of fats in the blood]and atrial fibrillation is crucial,” Zhao said.
3. Get 7 to 9 hours of sleep each night.
“Your body doesn't like extremes – rest gives your body time to recover,” Ning said. Keep your bedroom cool with air-con or fans. If you're sweating, move to a cooler room.
“Monitor indoor temperature and your physical condition in real time on summer nights,” He said.