吸烟和环境烟草烟雾暴露与膀胱癌关系的病例对照研究

目的研究分析吸烟及环境烟草烟雾暴露与膀胱癌的关系。方法自1996年1月~1999年6月,上海市区开展了一项大规模的基于全人群的膀胱癌病例对照研究,共访问到608例膀胱癌病例和607例健康人群对照。使用非条件logistic回归分析,调整可能的混杂因素,估计吸烟及环境烟草烟雾暴露对膀胱癌发生的比数比和95%可信区间。结果男性吸烟者患膀胱癌的危险性是不吸烟者的1.67倍(95%CI1.23~2.27),且随着每天吸烟量、累积吸烟量、吸烟年限和吸烟深度的增加而增加,吸烟开始年龄越小危险性越大;戒烟后膀胱癌危险性有所降低。吸烟也显著增加女性膀胱癌的危险性,调整OR为4.19(95%CI1.65~10.65)。吸烟者的调整人群归因危险度男性、女性分别为32.04%和15.61%。未发现环境烟草暴露增加非吸烟者膀胱癌的危险性。结论进一步证实吸烟是膀胱癌发生的重要危险因素。环境烟草烟雾暴露是否增加膀胱癌危险性尚难定论。

Relationship between smoking and exposure to environmental tobacco smoking with bladder cancer:a case-control study in Shanghai

Objective:To evaluate the relationship between smoking and environmental tobacco smoking(ETS)with the risk of bladder cancer. Methods:A population-based case-control study was conducted in Shanghai from Jan 1996 to Jun 1999. The dataset included 608 bladder cancer cases and 607 controls frequency matched for age and gender within 5 years. Detailed information on tobacco and ETS was collected through in-person interviews. Unconditional logistic regression models were used in the analysis to adjust potential confounding factors and to obtain maximum likelihood estimates of the odds ratios (ORs) and 95% confidence intervals(CIs). Results:Cigarette smoking was associated with a statistically significant 67% increase in the bladder cancer risk in man(OR=1.67;95%CI:1.23-2.27). The risk increased with increasing number of cigarettes smoked per day (two-sided P < 0.01 ,linear-trend test), as well as pack year,duration of smoking and earlier age started smoking. The reduced odds ratio was observed for bladder cancer among ex-cigarette smokers. Cigarette smoking increased the bladder cancer risk in women (OR= 4.19 ;95%CI:1.65-10.65). It was estimated that the proportion of bladder cancer attributable to smoking was 32.04% in men and 15.61% in women,respectively. No significant relationship was found between parents smoking in childhood,husband or room inmate smoking or due to ETS exposure at work place and bladder cancer risk. Conclusion:The findings support evidence that cigarette smoking increases the risk of bladder cancer. The effect of exposure to ETS on bladder cancer was uncertain in this study.