This study reports that heat-related MI risks increased over time, with significantly higher estimates in 2001-2014 compared to 1987-2000 for recurrent and NSTEMI events. Of note, cold-related MI risks nonsignificantly declined throughout the study period. These findings suggest that exposure to heat may be a potentially preventable trigger of MI events under a global warming climate. Mechanistically, high temperatures may lead to increased surface blood circulation and sweating, which may increase cardiac stress, blood viscosity, plasma cholesterol, and interleukin-6 levels. Additional studies are indicated to confirm these findings and develop strategies to mitigate heat as a potential trigger for MI.
