MMP-9基因-1562C/T变异与吸烟的交互作用对颈动脉易损斑块的影响

摘要

Objective To investigate the relationship between polymorphism of MMP-9 gene-1562C/T and susceptibility of instable carotid plaques.Methods Total 358 patients with ultrasonic diagnosed-carotid plaques were enrolled in the study,including 122 cases with instable carotid plaques (instable group) and 236 cases with stable carotid plaques (stable group).The MMP-9 genotypes were detected by PCR-RFLP.Chi-square test was used to compare the distribution of the genotype and allele frequency between two groups.And the interaction of-1562c/r mutation with smoking on susceptibility of instability of carotid plaques was analyzed using additive model.Results The frequency of CT and TT genotypes in carotid instable group was significantly higher than that in the stable group (20.90％ vs.11.65％,x2=10.91,P＜0.01),and the frequency of smoking was also higher (x2=9.74,P＜0.01).The qualitative analysis of interaction showed that compared to non-smokers carrying CC genotype,the OR value of smoker was 1.56 (P＜0.05),the OR value of carrying T allele was 1.67 (P＜0.05) and that of smokers carrying T allele was 3.60 (P＜0.01),there was an additive interaction between smoking and T allele.Multiple logistic regression showed that after adjusting the gender,age,BMI,blood press,HbA1c and LDL-C,there was a positive interaction between T allele and smoking on instability of carotid plaques.The synergy index of 2.12,the attributable interaction index of.36;the attributable interaction percentage was 37.78％,and pure attributable interaction percentage was 52.30％.Conclusion There is a synergy between the-1562C/T mutation of MMP-9 gene and smoking on instability of carotid plaques.The study indicates that for smokers carrying the T allele to quit smoking may decrease the risk of instability of carotid plaques.%目的 探讨MMP-9基因-1562C/T位点变异与颈动脉易损斑块的关系,及基因多态性和吸烟在颈动脉易损斑块易感性中的交互作用.方法 358例符合纳入标准的患者根据颈动脉超声分为易损斑块组(122例)和稳定斑块组(236例).采用PCR-RFLP方法检测两组-1562C/T位点基因型,比较两组基因型及等位基因频率分布差异,应用相加模型分析-1562C/T变异与吸烟对易损斑块的交互作用. 结果 易损斑块组携带T等位基因频率(20 90％)明显高于稳定斑块组(11.65％)(x2=10.91,P＜0.01),易损斑块组的吸烟率也明显高于稳定斑块组(x2=9.74,P＜0.01).T等位基因和吸烟对易损斑块交互作用的定性分析显示,相对于不吸烟且携带CC基因型个体,吸烟OR=1.56 (P＜0.05),T等位基因OR=1.67 (P＜0.05),同时吸烟又携带T等位基因OR=3.60 (P＜0.01),吸烟与T等位基因存在正相加模型交互作用.多元logistic回归分析显示:控制年龄、性别、BMI、血压、HbA1c和LDL-C等因素后,MMP-9基因-1562C/T变异T等位基因与吸烟的协同作用指数为2.12,归因交互效应为1.36,归因效应为37.78％,纯因子间交互作用为52.30％.结论 MMP-9基因-1562C/T变异与吸烟对颈动脉易损斑块的影响存在协同交互作用;对于携带T等位基因并吸烟的个体,尽早戒烟可能可以降低发生颈动脉易损斑块的风险.