Introduction: The strong, positive relationship between smoking and myocardial infarction was proven in the 1960s and 1970s. The prognostic significance of smoking in the acute phase of the infarction, and later in patients who survive the acute phase is, however, not clear. Numerous international studies focus on the phenomenon called the "smoker's paradox", which means that smokers have a lower mortality rate after suffering myocardial infarction than non-smokers. Although in many cases smoking does not have a positive effect on survival after controlling for confounders, an international consensus has not been reached regarding this issue.
Aim: The aim of this paper was to investigate whether the paradox effect exists in the case of Hungarian patients after controlling for the patients' risk profiles.
Method: The database used for the research was based on the 2014-2016 data of the Hungarian Myocardial Infarction Registry (n = 20 811) supervised by the Gottsegen György National Institute of Cardiology. The present analysis uses multivariate methodology to adjust for confounding: logistic regression is used for the short-term survival and survival analysis - with Cox proportional hazards model and Accelerated Failure Time models - is used for the long-term survival. Age, sex, performing of PCI, type of infarction (ST-elevation or not), creatinine abnormality, need for prehospital reanimation, cardiogenic shock and the presence of several comorbidities and medical history data were controlled for in the multivariate analysis.
Results: Both the short term - 30 day - mortality (OR = 1.517, 99% confidence interval: 1.229-1.872) and the long term mortality (HR = 1.395, 99% confidence interval: 1.232-1.579) were worse for smokers than non-smokers after adjusting for the abovementioned factors.
Conclusion: The "smoker's paradox" cannot be observed in the case of Hungarian patients, moreover smoking in itself is associated with worse prognosis. Orv Hetil. 2018; 159(14): 557-565.
Keywords: dohányzás; mortality; mortalitás; myocardial infarction; smoker’s paradox; smoking; survival; szívinfarktus; túlélés.