Smoking and the risk of sudden cardiac arrest in young-aged adults

초록

Aims: Smoking is a risk factor for cardiovascular events. Regarding the different etiology of sudden cardiac arrest (SCA) in younger individuals compared to the elderly, we investigated the linkage between smoking and the risk of SCA in young-aged adults. Methods: In this retrospective analysis, an observational longitudinal cohort was obtained from the national health screening database in South Korea. Adults aged between 20 to 39 years who underwent health screening from 2009 to 2012 were included. Smoking status was categorized as non-smokers, ex-smokers, and current-smokers. Burden of smoking was classified as mild (<10 pack-years), moderate (<20 pack-years), and heavy smokers (≥20 pack-years). Primary outcome was the occurrence of SCA during follow-up. Results: Among 6,293,672 individuals, mean age was 30.8 years, and median follow-up duration was 9.7 years. Comorbidities such as hypertension, diabetes mellitus, or dyslipidemia were rare. Non-smokers were most prevalent (55.2%), followed by current-smokers (34.8%) and ex-smokers (10.1%). Incidence of SCA increased from non-smokers (0.06 per 1,000 person-years), ex-smokers (0.08), and to current-smokers (0.14). Current-smokers showed increased risk of SCA compared with non-smokers (adjusted hazard ratio 1.69, 95% confidence interval 1.57 – 1.81, p<0.001). The risk of SCA was not increased in ex-smokers (0.96, 0.86 – 1.07, p<0.001). Higher smoking burden was associated with accelerated risk of SCA (adjusted hazard ratio in heavy smokers 2.15, 1.90 – 2.43, p<0.001). Conclusion: In young-aged adults, current smoking were associated with significantly increased risk of SCA in long-term follow-up. Risk of SCA showed linear association with cumulative burden of lifetime cigarette exposure.