Impact of the interaction between metabolic syndrome and smoking on the risk of cardiovascular events / 中华内分泌代谢杂志

ABSTRACT

Objective:To investigate the effect of the interaction between metabolic syndrome and smoking on the risk of subsequent cardiovascular events.Methods:Urban residents aged 40 and above in the Yunyan District of Guiyang City were selected from " Risk Evaluation of cAncers in Chinese diabeTic Individuals A lONgitudinal(REACTION) Study". The baseline survey started in 2011 and general information including gender, age, medical history, lifestyle habits, and smoking status were collected. Additionally, biochemical indicators related to metabolic syndrome(MS) were measured. The study participants were then followed up, and the first cardiovascular events occurring after the initial survey were recorded. The average follow-up period was 10.07±1.49 years. The interaction between metabolic syndrome and smoking on subsequent cardiovascular events was analyzed using Cox proportional hazards models.Results:The study included a total of 7 275 individuals, among whom 639 experienced cardiovascular events. After adjusting for multiple variables, compared to non-smokers without metabolic syndrome(MS), smokers with MS showed a higher risk of cardiovascular events, with a hazard ratio( HR) of 6.54(95% CI 4.88, 8.78). This risk was higher than that of individuals with MS who never smoked [ HR 1.39(95% CI 1.11, 1.75)] and non-MS smokers [ HR 2.48(95% CI 1.77, 3.49)]. There was an additive interaction between MS and smoking on the occurrence of cardiovascular events, with a relative excess risk due to interaction(RERI) of 3.30(95% CI 1.89, 4.70), an attributable proportion(AP) of 0.55(95% CI 0.43, 0.59), and a synergy index(S) of 3.07(95% CI 1.94, 4.84). Furthermore, when stratifying the duration of smoking cessation, long-term quitters(≥8 years) showed a lower risk of cardiovascular events compared to current smokers, regardless of whether they had MS. The hazard ratios were 0.45(95% CI 0.26, 0.78) for individuals with MS and 0.42(95% CI 0.19, 0.95) for individuals without MS. Conclusions:There is an additive interaction between smoking and MS on the risk of cardiovascular events. The coexistence of both factors significantly increases the risk of cardiovascular events.