Coronary disease & ACSCohort study

Short-Term Effects of Lower Air Temperature and Cold Spells on Myocardial Infarction Hospitalizations in Sweden

J Am Coll CardiolPublished

  • Case-crossover study
  • time-stratified
  • population-based
  • nationwide
  • conditional logistic regression with distributed lag nonlinear models

Authors' conclusion

This nationwide case-crossover study reveals that short-term exposures to lower air temperature and cold spells are associated with an increased risk of hospitalization for MI at lag 2 to 6 days.

Study context

Population
Myocardial infarction (MI) cases admitted to hospitals in Sweden during the cold season (October to March), 2005–2019
Participants
120,380 MI cases
Exposure
Lower air temperature and cold spells vs warmer referent days
Outcome
Hospitalization for MI (total MI, NSTEMI, STEMI)
Follow-up
Lag 0 to 1 (immediate) and 2 to 6 days (delayed)

Main finding

As reported in the abstract

Total MI, NSTEMI, STEMI per 1-U decrease in percentile temperature · lag 2 to 6 days
Odds ratio (95% CI)
1-U decrease in percentile temperaturetotal MI
1.099(1.057–1.142)
1-U decrease in percentile temperatureNSTEMI
1.110(1.060–1.164)
1-U decrease in percentile temperatureSTEMI
1.076(1.004–1.153)
Cold spellstotal MI
1.077(1.037–1.120)
Cold spellsNSTEMI
1.069(1.020–1.119)
Cold spellsSTEMI
1.095(1.023–1.172)

Per 1-U decrease in percentile temperature, as printed

Observational data: associations, not effects.

Further findings

MI at lag 0 to 1 days

Lower air temperature and cold spells associated with decreased risks for MI

Original publication

Short-Term Effects of Lower Air Temperature and Cold Spells on Myocardial Infarction Hospitalizations in Sweden. J Am Coll Cardiol. Published 1 September 2024. doi:10.1016/j.jacc.2024.07.006

Summarised from the published abstract; every number is checked against it