A prospective, population-based and nationwide Swedish study revealed that low air temperature, low atmospheric air pressure, high wind velocity, and shorter sunshine duration were associated with risk of myocardial infarction (MI) with the most evident association observed for air temperature. A total of 280 873 patients were included from 1998 to 2013, of whom 92 044 were diagnosed as having ST-elevation MI. Weather data were available for 274 029 patients (97.6%, mean age 71.7 years), which composed the final study population. Incidence of MI increased with lower air temperature, lower atmospheric air pressure, higher wind velocity, and shorter sunshine duration. The most pronounced association was observed for air temperature, where a 1-SD increase in air temperature (7.4°C) was associated with a 2.8% reduction in risk of MI (unadjusted incidence ratio, 0.972) and adaptation to cold may blunt this association. Results were consistent for non–ST-elevation MI as well as ST-elevation MI and across a large range of subgroups and health care regions. The findings are consistent with previous studies and suggest that the role of weather as a potential trigger of MI. Source: https://jamanetwork.com/
