Air pollution, high temperatures, and metabolic risk factors are driving global increases in stroke, contributing to 12 million cases and more than 7 million deaths from stroke each year, new data from the Global Burden of Disease (GBD) study showed.

Between 1990 and 2021, the number of people who experienced a stroke increased to 11.9 million (up by 70% since 1990), while the number of stroke survivors rose to 93.8 million (up by 86%), and stroke-related deaths rose to 7.3 million (up by 44%), making stroke the third leading cause of death worldwide after ischemic heart disease and COVID-19, investigators found.

Stroke is highly preventable, the investigators noted, with 84% of the stroke burden in 2021 attributable to 23 modifiable risk factors, including air pollution, excess body weight, high blood pressure, smoking, and physical inactivity.

This means there is "tremendous opportunities to alter the trajectory of stroke risk for the next generation," Catherine O. Johnson, MPH, PhD, co-author and lead research scientist at the Institute for Health Metrics and Evaluation (IHME), University of Washington, Seattle, said in a news release.

The study was published online on September 18 in The Lancet Neurology.