One growing global health issue is ambient air pollution. One of the leading risk factors for disease is fine particulate matter in outdoor air. The WHO states 1 in 8 deaths is due to air pollution. So what is it’s effect on cerebrovascular disease?

In Annals of Emergency Medicine from this month, a study was published that investigated air pollution in relation to ischemic strokes in Singapore (which is an urban island with millions living on it and a high GDP). It looked at all acute ischemic strokes from 2010 to 2015, numbering 29,384 cases, and compared it to an air quality index to indicate level of pollutants in the air. After adjusting for temperature, rain, and wind and stratified into subgroups by age and smoking status among other comorbidities, there was a significant positive association between stroke incidence and moderate to unhealthy ranges of pollutants in those >65 years who have never smoked, increasing the risk by about 5%. Incremental increases in the pollutant index led to increased risk of stroke incidence that were significant.  The risk was most pronounced the day of exposure but remained elevated for 5 days after.

So why would this affect you? 1. We are part of a global community. 2. The US has plenty of cities with high air pollution, especially in the setting of the California fires.  “Millions of people worldwide are exposed to seasonal high levels of air pollution from forest fires…” 3. Strokes cause death and disability. 4. Stroke codes are not fun. 5. Air doesn’t seem to be getting any cleaner. 6. You’re going to be older than 65 years old one day hopefully. There are plenty of advocacy groups, including with the American Lung Association. Carpool (or uberpool in most of our cases). Email your representative. Donate.


Ho, Andrew F.W. et al. The Relationship Between Ambient Air Pollution and Acute Ischemic Stroke: A Time-Stratified Case-Crossover Study in a City-State With Seasonal Exposure to the Southeast Asian Haze Problem. Annals of Emergency Medicine , Volume 72 , Issue 5 , 591 – 601.

June 2024