Strokes due to high temperature caused by climate change causes more than half a million deaths, healthcare departments expect more
A new study published in the journal Neurology paints a concerning picture: climate change is linked to a significant increase in stroke deaths worldwide. Researchers found that in 2019 alone, over half a million strokes could be attributed to extreme temperatures, both hot and cold. This number is projected to rise as the planet continues to warm.
The study, conducted by researchers at Xiangya Hospital Central South University in China, analyzed data on stroke incidence, temperature variations, and other climate factors across 204 countries and territories since 1990. Their findings revealed a disturbing trend: strokes linked to “non-optimal temperatures” have been steadily increasing across the globe, affecting people of all ages and genders.
While the total number of strokes naturally rises with population growth and aging, the study highlights a crucial difference. “Non-optimal temperatures,” meaning both extreme heat and cold, were found to be a significant contributing factor. In 2019, surprisingly, strokes associated with cold temperatures were more prevalent. This might seem counterintuitive, but climate change disrupts weather patterns, including the polar vortex. When this cold air mass weakens, it can lead to colder-than-average spells even in warming regions.
The burden of stroke deaths linked to extreme temperatures is currently concentrated in low- and middle-income countries with weaker healthcare systems. However, the rapid rise in heat-related strokes observed in Central Asia raises concerns about future impacts across the globe.
As global temperatures continue to climb, the study predicts a “sharp” increase in strokes caused by excessive heat. This aligns with the reality of a warming planet; 2023 saw record-breaking global temperatures, with March being the hottest month on record.
Dr. Mary Rice, a pulmonologist at Harvard Medical School, emphasizes the study’s significance. She commends the researchers for drawing attention to a critical health issue often overlooked. Dr. Rice further emphasizes the substantial number of stroke deaths attributable to non-optimal temperatures. Her recent research has also shown a link between climate change and a rise in immune-mediated diseases like allergies, asthma, and even cancers.
The stark conclusion: without immediate international action to curb greenhouse gas emissions and improve air quality, the world faces a future burdened by a much greater disease load.
Stroke is already a major health concern – the third leading cause of disability and a leading cause of death globally. This new study serves as a stark reminder of the additional health risks posed by climate change.
Extreme temperatures, both hot and cold, can have a detrimental effect on the body. In excessively hot conditions, the body struggles to regulate temperature, leading to a hypercoagulable state where blood clots more easily. Dehydration due to heat further strains the heart, increasing the risk of stroke and heart attack. Cold temperatures, on the other hand, trigger the fight-or-flight response, causing blood vessel constriction and a potential spike in blood pressure, again elevating stroke risk.
Dr. Ali Saad, a neurologist working with the Climate and Health Program at the University of Colorado, integrates climate awareness into his patient care. He advises patients on the dangers of extreme temperatures and even adds weather alerts to their phones.
This new research carries the potential to influence policy changes. Dr. Saad highlights the study’s significance in establishing the global reach of extreme temperatures as a risk factor for stroke. He emphasizes that neglecting this issue disproportionately harms low- and middle-income countries, but the threat extends far beyond. As the climate crisis intensifies, so will the burden of stroke and other health problems. The need for immediate international action is clear.
