Ed Cara, Gizmodo »

Heat waves appeared to pose a greater threat in general than cold snaps. Depending on the temperature and duration of extreme heat, for instance, the associated increased risk of death ranged from 18% to 74%, while the increased risk of cold days ranged from 4% to 12%. The highest associated risk was seen on days of extreme heat and heavy fine pollution, with heart attack deaths being roughly twice as likely to occur on these days than usual. Women and older adults also seemed to be more vulnerable than others. The team’s findings were published Monday in the journal Circulation.

These results can only show a correlation between extreme weather and heart attack deaths, not a clear cause-and-effect relationship. But this is only the latest research to suggest that very hot and cold days can be harmful to people’s health and hearts. Other studies have found that heart attacks in general become more common during extreme weather events. That said, there’s been less research looking at the impact of extreme weather on the risk of dying from a heart attack, according to the authors. This current study also suggests that extreme heat and pollution can have a synergistic effect on heart attack mortality.