Sizheng Peng,
Kai Du,
Hongyan Zhao,
Yingtao Zhang,
Ruiyi Chen,
Haiyu Zhang,
Kai Dong,
Hongxin Xu,
Yue Li,
Leilei Yin,
Yuhui Sun,
Tao Song
2026,
6(2):
65-75.
doi: 10.1515/fzm-2026-0007
Abstract:
Objective This study investigated the impact of daily ambient temperature and temperature changes between neighboring days (TCN) on the risk of ST-segment elevation myocardial infarction (STEMI) in cold regions using a time-series approach. Methods From January 1, 2017 to December 31, 2020, STEMI cases were collected from the largest medical center in Heilongjiang Province, excluding patients with incomplete data or unclear symptom onset times. Meteorological variables and air pollutant data corresponding to patients' residential address were matched from nearby monitoring stations. A distributed lag nonlinear model (DLNM) with a lag period of 0-21 days was applied to assess the effects of suboptimal temperatures on STEMI risk and lag structures. Different temperature indicators (maximum, mean, minimum, and TCN) were compared, and subgroup analyses by sex and age were performed to evaluate population-specific susceptibility. Results A total of 1461 days were included, comprising 4700 STEMI cases. Cold exposure was associated with a significant increase in STEMI incidence, with a delayed onset of 3 days and a prolonged effect lasting up to 20 days. In contrast, the heat effect was immediate and persisted for approximately 3 days. In the 21-day cumulative relative risk (CRR) analysis, using a median temperature of 6.6 ℃, the minimum morbidity temperature was identified at 17 ℃ (CRR 0.709, 95% CI 0.345-1.457). Notably, the highest incidence did not occur at the lowest temperature (-29 ℃, CRR 1.201, 95% CI 0.273-5.273). Instead, STEMI risk increased as temperatures rose from extreme cold, reaching a peak at -10 ℃ (CRR 1.63, 95% CI 0.905-2.936). Under conditions of extreme cooling (TCN = -11 ℃), STEMI risk increased from lag 0 to 7 (relative risk [RR] 2.239, 95% CI 0.279-17.936). Conclusions In cold regions, extreme temperatures, especially sustained cold exposure, significantly increase the risk of STEMI. Rapid temperature drops between consecutive days further elevate incidence, highlighting the importance of both absolute temperature and short-term temperature variability in cardiovascular risk.