Combo of extreme heat, air pollution may increase risk of deadly heart attack: study
Global News
During a two-day heat wave, the likelihood of a fatal heart attack increased by 18 per cent when temperatures ranged between 28 C and 37 C.
The combination of extreme heat and air pollution may significantly increase the risk of having a fatal heart attack, especially among older individuals, according to new research.
The study, published Monday in Circulation, looked at more than 202,000 heart attack deaths between 2015 and 2020 in China. It found that days with extreme heat, extreme cold or high levels of fine particle air pollution were significantly associated with the risk of a fatal heart attack.
“Extreme temperature events are becoming more frequent, longer and more intense, and their adverse health effects have drawn growing concern,” senior author Yuewei Liu, an associate professor of epidemiology at the School of Public Health at Sun Yat-sen University in China, said in a press release.
The researchers found that during a two-day heat wave, the likelihood of a fatal heart attack increased by 18 per cent when temperatures ranged between 28 C and 37 C. However, in a four-day heat wave, with temperatures ranging from 35 C to 43 C, the risk surged to 74 per cent.
The deaths were among older adults with an average age of 77.6 years; 52 per cent were older than age 80; and 52 per cent were male.
The researchers estimated up to 2.8 per cent of heart attack deaths may be attributed to the combination of extreme temperatures and high levels of fine particulate matter pollution.
“Another environmental issue worldwide is the presence of fine particulate matter in the air, which may interact with extreme temperatures to adversely affect cardiovascular health,” Liu said.
The risk of a fatal heart attack was found to be twice as high during four-day heat waves when the fine particulate pollution (PM 2.5) levels exceeded 37.5 micrograms per cubic meter. That is more than double what the World Health Organization recommends for a three to four-day duration, which is 15 micrograms per cubic meter.