Effect of Smoking Habit on and Cardiovascular Disease Among Patients With Newly Diagnosed Dyslipidemia Patients in Korea

Introduction: This study aimed to investigate the effects of smoking habit pattern on the risks of all-cause mortality and cardiovascular diseases (CVDs) among patients with newly diagnosed dyslipidemia using the Korean National Sample Cohort data. Methods: The study population consisted of 32,639 newly diagnosed dyslipidemia male patients from the Korean National Health Insurance Service – Health Screening Cohort during 2003-2012. Afterwards, the participants were followed-up until 31 December 2015 for cardiovascular disease event (CVD). Dyslipidemia was defined as those who were prescribed statin medication under the International Classification of Disease, Tenth Revision (ICD-10) codes for dyslipidemia (E78). CVD was composed to coronary heart disease (CHD, ICD-10 codes I20-25) and total stroke (ICD-10 codes I60-69). Cox proportional hazards regression analysis was used to determine the risk of developing CVD according to smoking habit change before and after diagnosis of dyslipidemia. Results: Quitters (adjusted hazard ratio [aHR], 0.82; 95% confidence interval [CI], 0.68–0.99) , sustained ex-smokers (aHR 0.71, 95% CI 0.62-0.82) and never smokers (aHR 0.70, 95% CI 0.62-0.80) showed reduced risk of CVD compared with continual smokers. Quitters also tended to have reduced risk for CHD (aHR 0.83, 95% CI 0.66-1.05) and acute myocardial infarction (aHR 0.68, 95% CI 0.44-1.05) compared to continual smokers. Finally, compared to continual smokers, those who quit after dyslipidemia diagnosis tended to have reduced risk for total stroke (aHR 0.84, 95% CI 0.64-1.11).Our study suggested smoking reduction after dyslipidemia diagnosis may have potential positive effects and have definite benefits on the health outcomes. Conclusion: Smoking cessation after dyslipidemia diagnosis could reduce the risks of cardiovascular disease among patients with newly diagnosed dyslipidemia. Therefore, physicians should advice patients with newly diagnosed dyslipidemia on the importance of smoking cessation in order to reducing risk for CVD.