吸烟与结直肠癌诊断年龄关系的研究

Study on Correlation between Smoking and Age at Diagnosis of Colorectal Cancer

吸烟与结直肠癌的发病率和死亡率显著相关。国外研究发现吸烟的结直肠癌患者平均诊断年龄显著低于不吸烟的结直肠癌患者，而国内相关报道尚少。目的：分析不同吸烟变量与结直肠癌诊断年龄之间的关系。方法：以面访问卷调查的方式收集628例连续性结直肠癌患者的资料。先以单因素方差分析筛选出与男性结直肠癌患者诊断年龄相关的吸烟变量．再采用协方差分析均衡混杂因素，比较各吸烟变量不同暴露水平间诊断年龄的差异。结果：男性结肠癌患者中，吸烟者的诊断年龄较不吸烟者提前6．0岁（P=O．031）。吸烟状态、开始吸烟年龄和吸烟年限这三个吸烟变量与诊断年龄相关；均衡混杂因素后，与从未吸烟者相比．开始吸烟年龄≤16岁和吸烟年限15-34年的男性结直肠癌患者诊断年龄分别提前7．89岁（P=O．0420）和5．1l岁（降0．0127）。结论：男性较早开始吸烟和长期吸烟与结直肠癌尤其是结肠癌的发生年龄提前相关。在普通危险人群中．对于开始吸烟年龄≤16岁或吸烟年限15-34年的男性，结直肠癌筛查的起始年龄应提前5-10岁。

Cigarette smoking is significantly associated with the incidence and mortality of colorectal cancer. Studies abroad found that smokers had lower mean age at diagnosis of colorectal cancer than nonsmokers, however, only few domestic studies have been focused on this issue. Aims： To analyze the correlation between smoking variables and age at diagnosis of colorectal cancer. Methods： Data of 628 consecutive colorectal cancer patients were collected through face to face questionnaires. The smoking variables correlated with age at diagnosis of male colorectal cancer patients were selected by one-way ANOVA, and then covariance analysis was used to adjust confounding factors and compare the differences in age at diagnosis under different exposure levels of each smoking variable. Results： For colon cancer, age at diagnosis of male smokers was 6.0 years earlier than those never smoking （P=0.031）. Three variables including smoking status, age of starting smoking and smoking years were identified to be correlated with age at diagnosis. Compared to nonsmokers, adjusted age at diagnosis of colorectal cancer were 7.89 years （P=0.0420） and 5.11 years （P=0.0127） earlier in males who started smoking ~〈 16 years old and smoked for 15-34 years, respectively. Conclusions： Exposure to tobacco at early age and long-term smoking may lead to early onset of colorectal cancer, especially colon cancer in males. Screening for colorectal cancer in average-risk people should be initiated 5-10 years earlier for male smokers who start smoking≤16 years old or smoke for 15-34 years.