High temperatures and pollution driving rise in strokes across Middle East

Region has world’s highest levels of dangerous air pollution particles

Smog over Cairo, Egypt. A new study has linked air pollution in the region to stroke levels. Reuters

High temperatures and air pollution are contributing to rises in strokes across the Middle East and Africa, a study has found.

The regions have among the highest stroke rates worldwide, according to the research, which will be presented at the World Stroke Congress in Abu Dhabi in October.

Globally, about 12 million strokes occur each year, causing seven million deaths, according to the study, published in The Lancet Neurology journal.

Between 1990 and 2021, the number of people having their first stroke increased by up to 70 per cent, while deaths due to the condition rose by up to 44 per cent.

Loss of good health due to strokes also increased by about a third during the period. The Middle East, North Africa and sub-Saharan Africa fared worse than most regions during the period, losing more time due to ill health from strokes.

“From 1990 to 2021, the age-standardised proportion of stroke DALYs [time due to ill health] attributable to risk factors increased in North Africa and the Middle East and sub-Saharan Africa,” said the study, “but did not change in south Asia and South-east Asia, East Asia, and Oceania, and decreased in central Europe, eastern Europe, and central Asia, Latin America and the Caribbean, as well as high-income GBD [global burden of disease] regions.”

The rise may “reflect a failure in the control of risk factors” in the regions, said the report. The study identified 23 risk factors, including air pollution, excess body weight, high blood pressure, smoking and physical inactivity.

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It found the contribution of high temperatures to poor health and early death due to stroke has risen 72 per cent since 1990, a trend likely to continue to increase due to the worsening impact of climate change.

The study also revealed for the first time the high contribution – on par with smoking – of particulate matter air pollution to fatal brain bleeds known as subarachnoid haemorrhage.

“This study is, to our knowledge, the first to show the large contribution of ambient particulate matter pollution and household air pollution from solid fuels to subarachnoid haemorrhage, with a similar [relationship] to that of smoking.”

It found that air pollution in 2021 appeared to be “highly important” to other types of stroke, causing 11.9 per cent of total deaths from all causes, making it the second largest cause of deaths from all causes globally, after high systolic blood pressure.

“These findings are in line with research showing that rises in ambient temperature (including heatwaves) and climate change are associated with increased stroke morbidity and mortality,” added the study.

The Middle East has the world’s highest levels of dangerous air pollution particles, which are responsible for millions of heart disease deaths globally each year, according to a recent report.

The World Heart Foundation (WHF) study found that Kuwait, Egypt and Afghanistan have the worst concentrations of particles less than 2.5 micrometres in diameter (PM2.5), which come from sources that include vehicle exhaust fumes, power plant combustion and burning wood.

Globally, almost 7 million deaths were attributed to air pollution in 2019 – a higher mortality toll than all wars, malaria, tuberculosis, HIV and other infectious diseases combined, according to the WHF.