Log in to MyACC
Triggering of MI by Air Temperature
Study Questions:
What are the temporal variations in the association between short-term exposures to air temperature and myocardial infarction (MI)?
Methods:
The investigators recorded a total of 27,310 cases of MI and coronary deaths over a 28-year period from 1987-2014. Daily meteorological parameters were measured in the study area. A time-stratified case-crossover analysis with a distributed lag nonlinear model was used to estimate the risk of MI associated with air temperature. Subgroup analyses were performed to identify subpopulations with changing susceptibility to air temperature.
Results:
Results showed a nonsignificant decline in cold-related MI risks. Heat-related MI relative risk significantly increased from 0.93 (95% confidence interval [CI], 0.78-1.12) in 1987-2000 to 1.14 (95% CI, 1.00-1.29) in 2001-2014. The same trend was also observed for recurrent and non–ST-segment elevation MI (NSTEMI) events. This increasing population susceptibility to heat was more evident in patients with diabetes mellitus and hyperlipidemia. Future studies using multicenter MI registries at different climatic, demographic, and socioeconomic settings are warranted to confirm these findings.
Conclusions:
The authors concluded that there is evidence of rising population susceptibility to heat-related MI risk, suggesting that exposure to heat should be considered as an environmental trigger of MI.
Perspective:
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.
Keywords: Acute Coronary Syndrome, Blood Viscosity, Cholesterol, Climate Change, Cold Temperature, Diabetes Mellitus, Global Warming, Hot Temperature, Hyperlipidemias, Interleukin-6, Myocardial Infarction, Risk, Secondary Prevention, Sweating, Temperature
< Back to Listings
