Climate change and air pollution are compounding the global burden of stroke, according to a new review published by the World Stroke Organization. The research, which synthesizes decades of published studies, warns that environmental shifts—from heatwaves and cold snaps to wildfires and dust storms—are increasingly linked to both the incidence and lethality of strokes.
For Europe, where the population is aging and fossil fuel dependence remains entrenched, the findings carry particular urgency. The continent has already experienced record-breaking temperatures and worsening air quality, as documented by the Copernicus Climate Change Service. Europe's climate crisis now poses an unequivocal threat to health, and stroke is emerging as a key indicator of that danger.
How Climate Factors Affect Stroke Risk
The review, led by Dr. Anna Ranta of the University of Otago in Wellington, New Zealand, examined evidence linking stroke to a range of climate-related environmental changes. These include extreme heat and cold, rapid temperature shifts, humidity, barometric pressure fluctuations, wildfires, and sandstorms. While most studies show associations rather than direct causation, the researchers stress that the overall pattern is consistent and biologically plausible.
“Hot temperatures can cause dehydration, ‘thickening’ the blood and raising the risk of blocked blood vessels, while humidity and air pressure changes can increase blood pressure, an important cause of stroke,” Ranta explained. She added that combined weather extremes—such as heat with drought, or cold with humidity and wind—can have an additive effect, further elevating stroke risk and mortality.
Certain populations are disproportionately affected. Older adults, individuals with metabolic disorders, and people living in colder or lower-income regions face higher risks. In Europe, this includes vulnerable communities in the Balkans and parts of Eastern Europe, where both cold and heat extremes contribute heavily to the stroke burden.
Air Pollution: A Shared Culprit
The World Stroke Organization also highlights air pollution as a major stroke risk factor. Its latest Global Stroke Fact Sheet estimates that environmental risk factors—primarily air pollution and lead exposure—account for roughly 37% of the global stroke burden. Particulate matter from pollutants enters the bloodstream through the lungs, damaging blood vessel walls and leading to blocked or ruptured brain arteries.
Because climate change and air pollution share a common source in the burning of fossil fuels, reducing greenhouse gas emissions could simultaneously lower stroke risks and protect brain health. This connection places European energy policy at the center of public health strategy. EU Climate Chief Wopke Hoekstra has urged an end to new fossil fuel drilling, a move that would align climate goals with stroke prevention.
However, Europe's energy transition remains uneven. Croatia recently signed a US-backed gas deal to expand Balkan pipelines, a decision that raises tensions between short-term energy security and long-term climate and health objectives. Such investments risk locking in fossil fuel infrastructure for decades, perpetuating both emissions and air pollution.
The review's authors call for integrated policies that address climate mitigation and air quality simultaneously. For European governments, this means accelerating the shift to renewable energy, tightening emission standards, and investing in early warning systems for extreme weather events. As the continent grapples with the health consequences of a warming planet, stroke prevention offers yet another compelling reason to act.
