The impact of winter cold weather on acute myocardial infarctions in Portugal

► We model the relationship between daily hospitalizations due to myocardial infarctions and cold weather in Portugal. ► We use Physiological Equivalent temperature (PET) as main explanatory variable. ► We adjust the models to confounding factors such as influenza and air pollution. ► Daily hospitalizations increased up to 2.2% per degree fall of PET during winter. ► Exposure to cold weather has a negative impact on human health in Portugal.