A Stroke can Strike Your Heart as Global Temperatures Change

Highlights:

Climate changes can increase the number of stroke cases
Temperature increases, temperature drops, and humidity changes can all be precursors to stroke
Stroke can be //avoided by maintaining our current environment and making minor lifestyle changes

Stroke is one of the leading causes of death and disability worldwide, and now there is a well-established link between stroke and temperature change.

"Climate change and global warming are worldwide problems, and stroke is a leading cause of death," said study author Dr. Ryohei Fujimoto of Tsuyama Central Hospital and the Department of Epidemiology at the Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Japan.

Sudden Drop in Temperature May Up Stroke Mortality
Sudden cold weather or drop in temperature may increase the number of deaths from stroke, especially among people over 65. The incidence of stroke associated with the colder weather was higher among older women.

‘Effect modification revealed that high temperatures in hot months can trigger first-ever strokes, and low atmospheric pressure may exacerbate the effect. Low temperatures, on the other hand, can increase the risk of stroke.’

There is limited research on the effects of high temperatures on stroke risk. This study looked at the relationship between heat exposure and emergency room visits for stroke in older people. The survey involved 3,367 Okayama, Western Japan, residents. Participants were 65 or older and were taken to emergency rooms between 2012 and 2019 for the development of a stroke during and in the few months following the rainy season.

Temperature and stroke were studied during the monsoon season, one month later, two months later, and three months later. The researchers used a time-stretched case-crossover study design, comparing the temperature on the day of the week when a stroke occurred to the temperature on the same day of the week when no strokes happened within the same month for each participant. Individual traits, long-term time patterns, seasonality, and day of the week were avoided as they were potential confounding factors.

The researchers discovered that one month after the rainy season, the association between temperature and stroke was at its highest. After controlling for relative humidity, barometric pressure, and PM2.5 concentration, each 1°C increase in temperature increased the likelihood of emergency visits for stroke by 35%. Each 1°C increase in temperature was associated with a 24% greater likelihood of hemorrhagic stroke, a 36% increased risk of ischemic stroke, and a 56% increased risk of transient ischaemic attack when each kind of stroke was examined independently.

Prolonged Exposure to High Temperature Could Lead to Heat Stroke
Heat waves, times of excessively hot weather that include spikes in temperature, can also occur during the summer. Both can create a number of health problems.

In a second analysis, the researchers evaluated whether there was a possible "effect modification" according to the rainy season. Effect modification means that the association between exposure (hot air temperature) and outcome (emergency visit for stroke) may be different depending on a third variable (during and after the rainy season). For this analysis, the reference period was the rainy season. Again, the relationship was strongest one month after the rainy season. Compared with the reference period, there was a 31% elevated likelihood of stroke for each 1°C rise in temperature.

Dr. Fujimoto explained, "The results of the second analysis suggest that environmental conditions immediately after the rainy season intensify the relationship between hot weather and stroke. In addition to high temperatures, this period is characterized by an increase in sunshine duration and less rain, which may explain the findings."

What are Heat Stroke Symptoms?
Raised body temperature, flushed dry skin, confusion, and breathing difficulty are some of the symptoms of heat stroke.

He concluded, "Our study suggests that older adults should try to keep cool during hot spells, for example by staying indoors during peak temperatures. Public health systems can help by providing cool spaces for members of the public to escape the heat during the hottest months of the year."

Why do Temperature Changes Cause Stroke?

There is a direct relationship between high and low temperatures and stroke risk. Earlier, stroke was dubbed "the sickness of cold weather." This is because exposure to a sudden decrease in temperature is directly linked to increased stroke risk through altering blood viscosity and/or triggering infections.

And now there are evidence-based studies that also indicate an increased risk of stroke during high temperatures.

What are the Causes of Heat Stroke?
Heat stroke usually results from doing heavy work in hot environments usually accompanied by inadequate fluid intake.

Heat stroke is a known cause of ischemic venous and arterial stroke, contributing to mortality and morbidity in extreme hot weather, especially when hot weather is combined with humidity.

In a stroke-prone individual, a low body temperature caused by insufficient fluid intake and a high body temperature caused by excessive fluid loss cause hemoconcentration, which can lead to an increased risk of ischemic stroke.

How to Protect and Prevent a Stroke in Your Heart

With this research, it is clear that older adults may be more susceptible to stroke after exposure to hot weather. Preventative measures such as insulated housing and air conditioning should be considered a public health priority to protect people from this debilitating and life-threatening disease.
Maintaining constant blood pressure regulation by reducing salt intake.
Staying indoors and seeking to regulate body temperature by utilizing air conditioning in the summer and heat in the winter.
Exercise moderately or do some mild exercise.
Avoid unhealthy foods, red meat, and a diet with high salt content, and follow a healthy diet.

Source-Medindia