Prevalence and Mortality Risk of Persistent Smoking After Myocardial Infarction in a Very-High-Risk Region of Southeastern Europe.

Background and Objectives: Long-term real-world data regarding smoking cessation after myocardial infarction (MI) remain scarce in Southeastern Europe. Our objective was to estimate the prevalence of smoking status categories and to assess their association with long-term all-cause mortality in percutaneous coronary intervention (PCI) treated MI patients. Materials and Methods: We retrospectively collected data from electronic medical records of hospitalized MI patients who underwent PCI from 1 January 2016 to 1 January 2019. Smoking status and primary outcome (all-cause mortality) were assessed at baseline, during follow-up visits, and during teleconsultation until January 2024, and patients were categorized accordingly. Results: Never-smokers were older than persistent smokers (67.6 ± 11.4 vs. 57.3 ± 9.6 years; p < 0.01) and had a higher burden of hypertension and diabetes (both p < 0.01). At baseline, 47.9% were active smokers, 32.3% of them quit after an MI (with 77.7% being men). Over a median follow-up of 6.7 years, 220 deaths (17.3%) occurred. In a Cox regression model adjusted for age, persistent post-MI smoking significantly increased mortality risk (aHR 2.18; 95% CI 1.52-3.12; p < 0.001), former smokers had an aHR was 1.07 (p = 0.694), while quitters had 30% reduction in death risk (aHR 0.69; p = 0.217). Additionally, in the fully adjusted model, besides persistent smoking (aHR 2.18; p = 0.001), diabetes (aHR 1.69; p = 0.001) and age (aHR 1.09; p < 0.001) were independent predictors of all-cause mortality. Conclusions: Post-MI smoking more than doubles mortality risk, while sustained cessation reduces risk to near never-smoker levels, underscoring the need for aggressive, tailored cessation strategies in low-quit-rate regions such as Southeastern Europe.