Objective: To examine the sex-specific associations between tobacco smoking and risk of cardiovascular diseases in Chinese adults. Methods: The present analysis included 487 373 participants from the China Kadoorie Biobank after excluding those with cancer, heart diseases, stroke at baseline survey. The baseline survey was conducted from June 2004 to July 2008. The number of follow-up years was calculated from the time that the participants completed baseline survey to the time of any event: CVD incidence, death, loss of follow-up, or December 31, 2015, whichever occurred first. We used Cox proportional hazards regression models to estimate the HRs and 95%CI of incident cardiovascular diseases with tobacco smoking. Results: During a median follow-up of 8.9 years(a total of 4.1 million person years), we documented 33 947 cases of ischemic heart diseases, 6 048 cases of major coronary diseases, 7 794 cases of intracerebral hemorrhage, and 31 722 cases of cerebral infarction. The prevalence of smoking was much higher in men (67.9%) than in women (2.7%). Smoking increased risk of all subtypes of cardiovascular diseases. Compared with nonsmokers, the multivariable-adjusted HRs (95% CI) for current smokers were 1.54 (1.43-1.66) for major coronary event, 1.28 (1.24-1.32) for ischemic heart disease, 1.18 (1.14-1.22) for cerebral infarction, and 1.07 (1.00-1.15) for intracerebral hemorrhage, respectively. Female smokers tended to have greater risk of developing major coronary event associated with amount of tobacco smoked daily (interaction P=0.006) and age when smoking started (interaction P=0.011). There was no sex difference in these two effects for ischemic heart diseases, intracerebral hemorrhage and cerebral infarction (all interaction P>0.05). Conclusions: This prospective study confirmed increased risk of all subtypes of cardiovascular diseases in current smokers. Smoking was more harmful to women than to men for major coronary event.
目的： 分析中国成年人吸烟与不同心血管疾病发病风险的关联及其性别差异。 方法： 研究对象来自中国慢性病前瞻性研究，基线调查开展于2004年6月至2008年7月，剔除基线自报患有恶性肿瘤、冠心病、脑卒中的个体，最终纳入487 373名研究对象。随访人年数的计算从研究对象完成基线调查时开始，至最早出现以下任一事件的时间为止：心血管疾病（CVD）发病、死亡、失访或2015年12月31日。使用Cox比例风险模型计算吸烟行为特征和心血管疾病发病风险的关联。 结果： 研究对象平均随访8.9年。随访期间新发缺血性心脏病33 947人，急性冠心病事件6 048人，脑内出血7 794人，脑梗死31 722人。男性吸烟率（67.9%）远高于女性（2.7%）。与非吸烟者相比，吸烟能增加各类CVD结局的发病风险，风险效应值HR值（95%CI）由大到小依次为急性冠心病事件1.54（1.43~1.66）、缺血性心脏病1.28（1.24~1.32）、脑梗死1.18（1.14~1.22）、脑内出血1.07（1.00~1.15）。当前吸烟者中，每天吸烟量和开始吸烟年龄与急性冠心病事件风险间的关联存在性别差异（性别交互作用P值分别为0.006、0.011），主要表现为女性吸烟者风险高于男性。每天吸烟量和开始吸烟年龄与缺血性心脏病、脑内出血和脑梗死之间的关联均未见性别差异（性别交互作用P>0.05）。 结论： 吸烟能够增加各类CVD的发病风险，而女性吸烟者发生急性冠心病事件的风险远高于男性。.
Keywords: Cardiovascular diseases; Sex specific difference; Tobacco smoking.