A new study published in the journal Circulation, the journal of the American Heart Association (AHA), has found that certain groups of people may have twice the risk of dying from heart attacks during heat waves and high levels of fine particulate pollution. The researchers analyzed over 202,000 heart attacks that occurred in the Chinese province of Jiangsu between 2015 and 2020. They discovered that days with extreme heat, extreme cold, or high levels of fine particulate matter air pollution were linked to a higher risk of death from cardiac events. The study focused on Jiangsu due to its wide range of temperatures and fine particulate pollution levels.

To determine when a heat wave was occurring, the researchers used the daily heat index, which measures a combination of heat and humidity. The study found that the risk of death from a heart attack was twice as high during four-day heat waves with fine particulate pollution levels above 37.5 micrograms per cubic meter. The risk was highest among women and older adults, with the average age of death from heart attacks being 77.6. Over 52% of those who passed away were older than age 80.

Dr. Yuewei Liu, the senior author of the study and an associate professor of epidemiology in the School of Public Health at Sun Yat-sen University in Guangzhou, China, stated that extreme temperature events are becoming more frequent, longer, and more intense, causing growing concern for their adverse health effects. Additionally, the presence of fine particulate matter in the air, which may interact with extreme temperatures, is another environmental issue worldwide that adversely affects cardiovascular health.

Dr. Alexander Postalian, a cardiologist at The Texas Heart Institute, commented on the findings, stating that exposure to extreme heat not only increases the risk of heat exhaustion and heat stroke, but also puts stress on the cardiovascular system, making the heart work harder. This increased exertion can raise the risk of heart attacks or heart failure. He referred to the combination of extreme heat and extreme pollution as a "perfect storm" that causes stress on an individual's cardiovascular system, increasing the risk of heart issues.

To prevent the risk of death from heart attacks, the study researchers recommended reducing exposure to both extreme temperatures and fine particulate pollution. Strategies included following weather forecasts, staying inside during extreme temperatures, using fans and air conditioners, dressing appropriately, staying hydrated, and installing window blinds to reduce indoor temperatures. They also suggested using air purifiers in the house, wearing masks outdoors, avoiding busy highways when walking, and choosing less strenuous outdoor activities on days with high levels of fine particulate pollution.

Individuals with a history of heart disease or other significant cardiovascular problems were advised to watch for chest pain or shortness of breath, take shorter walks outside, and limit total time spent outside during extreme heat conditions. Dr. Postalian warned that certain medications, such as diuretics, can increase the likelihood of dehydration, which can cause a drop in blood pressure and increase the risk of injuries from falls. He emphasized the importance of drinking plenty of fluids to avoid dehydration. People taking cardiovascular medications or suffering from heart disease were advised to avoid spending prolonged time in temperatures above 100 degrees and to consult with their doctors about ways to protect themselves from extreme weather conditions.