竞争风险模型在吸烟与缺血性脑卒中复发关系研究中的应用

目的 探讨吸烟与缺血性脑卒中患者复发的关系。方法 对首发卒中患者进行随访观察，采用竞争风险模型，分性别建模，探讨男性吸烟、女性被动吸烟与脑卒中复发的关系。结果 本研究最终共纳入初发缺血性脑卒中患者594例进行分析，男性361例（复发59例，竞争事件13例），女性233例（均为非吸烟者，复发49例，竞争事件11例）。校正混杂因素后，相对于既无主动又无被动吸烟的男性而言，除无主动仅有被动吸烟的男性相对危险度对应 P值为0.050外(SHR=3.040)，吸烟指数第二分组（100~200 支年）相对危险度为0.947外，虽然其余各对比组SHR均大于1，但差异均无统计学意义。本研究也未发现吸烟指数等级和累积吸烟量与缺血性脑卒中复发有关。相对于无被动吸烟的女性而言，基线有而随访时无被动吸烟组危险比为1.4,其余各对比组相对危险度均小于1，无统计学意义。结论 本次研究尚未发现吸烟与缺血性脑卒中复发有关系，尚需更大样本的研究进行验证。

Determination of the Association Between Smoking and Recurrence of Ischemic Stroke using a Competing

Objective To determine the association between smoking and ischemic stroke recurrence. Methods We conducted a prospective follow-up study of patients with first incidence of stroke. A competing risks model was used to establish the association between smoking and stroke recurrence. Results A total of 594 stroke patients were recruited. Among the 361 male patients, 59 recurrent events and 13 competing events occurred. Among the 233 female patients (all were non-smokers), 49 recurrent events and 11 competing events occurred. Adjusted for confounding factors, male nonsmokers exposed to passive smoking had a SHR of 3.040 in comparison with those without exposure to smoking and the P value was borderline significant. Those who smoked 100-200 cigarettes a year had a SHR of 0.947. The other groups with exposure to smoking had a greater than 1 SHR, but without statistical significance. Moreover, no significant associations between recurrence of ischemic stroke and smoking index/cumulative smoking were found. The female nonsmokers who had exposure to passive smoking only at follow-ups had a SHR of 1.4 （and all other groups had less than 1 SHR）. But no statistical significances were found in the comparisons. Conclusion Further research with a larger sample size is needed to establish the association between smoking and recurrence of ischemic stroke.