Influence of daily temperature on the occurrence of ST-elevation myocardial infarction

Abstract

BackgroundEpidemiological studies reported that acute myocardial infarction (AMI) occurs more often in winter season or days with low temperatures. However, most of these studies did not distinguish ST-elevation myocardial infarction (STEMI) from AMI. The purpose of this study was to investigate the relationship between temperature and the occurrence of STEMI. MethodsWe reviewed all daily temperature in Saitama City between January 2015 and December 2021 (2557 days) and divided them into days in which our institution received STEMI (days with STEMI) and days in which our institution did not receive STEMI (days without STEMI). ResultsThe daily maximum temperature was significantly lower in days with STEMI than in days without STEMI [20.0 °C (68.0 °F) versus 21.2 °C (70.2 °F), p = 0.001]. The maximum temperature was significantly lower in days with STEMI than in days without STEMI in the elderly [19.9 °C (67.8 °F) versus 21.1 °C (70.0 °F), p = 0.003], whereas this trend was weaker in the non-elderly [20.2 °C (68.4 °F) versus 20.9 °C (69.6 °F), p = 0.171]. Furthermore, the maximum temperature was significantly lower in days with STEMI than in days without STEMI in male [20.0 °C (68.0 °F) versus 21.1 °C (70.0 °F), p = 0.002], whereas this trend was weaker in females [20.0 °C (68.0 °F) versus 20.9 °C (69.6 °F), p = 0.169]. ConclusionsThe daily temperatures were significantly lower in days with STEMI than in days without STEMI, and this relationship was pronounced in elderly or male patients.