Long-Term Air Pollution Exposure Linked to Increased Risk of Blood Clots: NIH Study

According to a Dec. 12 press release, a study found that more exposure to long-term air pollution is linked with increased risks for blood clots in deep veins.

The press release said, “These findings came from a longitudinal study funded by the National Institutes of Health (NIH) that included 6,651 U.S. adults who were followed for an average of 17 years between 2000 and 2018. Participants lived in or near one of six major metropolitan areas: New York, Baltimore, Chicago, Los Angeles, Minneapolis, and Winston-Salem, North Carolina.”

Further, “Throughout the study, 248 adults, 3.7% of the study sample, developed blood clots in deep veins that required hospital care. The likelihood of this outcome was linked to anywhere from a 39% to a more than two-fold increased risk based on long-term exposure to three different types of air pollutants.”

Blood clots in deep veins are known as venous thromboembolism (VTE), including deep vein thrombosis. This occurs when a blood clot forms in a deep vein of the legs, arms, or an internal organ, and pulmonary embolism, which occurs when a blood clot breaks off from a deep vein and travels to the lungs.

Exposure to air pollution has been associated with cardiovascular and respiratory diseases for quite some time. Previous research suggested a link to VTE, this is the largest, most comprehensive U.S. study to report that association with three different types of air pollutants.

The press release added, “VTE affects up to 900,000 Americans(link is external) each year. Many cases occur after surgery, but other factors, including age, long periods of inactivity, heart disease, pregnancy, and genetics, can increase risks.”